An observational study was conducted in Maputo, Mozambique, to investigate trends in prevalence of HIV drug resistance (HIVDR) in antiretroviral (ART) naïve subjects initiating highly active antiretroviral treatment (HAART).To evaluate the pattern of drug resistance mutations (DRMs) found in adults on ART failing first-line HAART [patients with detectable viral load (VL)]. Untreated subjects [Group 1 ] and 274 treated subjects with variable length of exposure to ARV´s  were enrolled. Virological and immunological failure (VF and IF) were measured based on viral load (VL) and T lymphocyte CD4+ cells (TCD4+) count and genotypic resistance was also performed. Major subtype found was C . Maximum virological suppression was observed in G3, and significant differences intragroup were observed between VF and IF in G4 (p=0.022). Intergroup differences were observed between G3 and G4 for VF (p=0.023) and IF between G2 and G4 (p=0.0018). Viral suppression (<50 copies/ml) ranged from 84.9% to 90.1%, and concordant VL and DRM ranged from 25% to 57%. WHO cut-off for determining VF as given by 2010 guidelines (>5000 copies/ml) identified 50% of subjects carrying DRM compared to 100% when lower VL cut-off was used (<50 copies/ml). Length of exposure to ARVs was directly proportional to the complexity of DRM patterns. In Mozambique, VL suppression was achieved in 76% of individuals after 24 months on HAART. This is in agreement with WHO target for HIVDR prevention target (70%).We demonstrated that the best way to determine therapeutic failure is VL compared to CD4 counts. The rationalized use of VL testing is needed to ensure timely detection of treatment failures preventing the occurrence of TDR and new infections. Mozambique, a sub-Saharan country with HIV prevalence of 11.5% ,3. The aTreatment options are based on WHO guidelines for treating HIV infected people in low income countries. First-line regimen comprises two NRTI [stavudine/zidovudine and lamivudine (d4T/AZT and 3TC)] and one NNRTI [nevirapine/efavirenz (NVP/EFV)] whereas a PI based HAART is used for second line regimen mostly composed by Aluvia (LPV boosted RTV). Monitoring of treatment is performed using immunological parameters (CD4+ T lymphocyte counts) and clinical criteria ,3,5.The effectiveness of first-line therapies in decreasing morbidity and mortality has been documented in several reports –9. HowevEffective ARV programs rely on the maintenance of sustainable viral suppression preventing the occurrence of both new infections and transmission of drug resistance (TDR) strains as well vertical transmission of HIV+ pregnant women . Althougst line using, viral load measurement comparing to CD4 response, and defining RAMs profile.Cross resistance to other NNRTI´s, including next generation inhibitors, is seen with mutation Y181C resulting from a change from tyrosine to cysteine at position 181 . In a co3 following the country ARV guideline. In order to compare the virological significance of viral load cutoff above and below 5000 copies/ml, two cut-off points for virological failure (VF) were defined in this study: viral load ≤50 copies/ml (study cutoff) and ≤5000 copies/ml .The study was conducted at Alto Maé Health Centre at the capital Maputo, one of the first sites to provide HAART in the country. Study group consisted of drug naive HIV positive adult subjects and subjects on first-line treatment for different periods (> 6 months). Pregnancy, low adherence and active opportunistic infections were the main exclusion criteria. Virological failure was defined as viral load >50 copies/ml immunological failures was primarily defined as TCD4+ count below 200 cells/mmInformed written consent was given to all potential participants, and signed by consenting subjects. Study protocol, including consent procedures were approved by the appropriate national ethics review committee in Mozambique.pol gene spanning the complete PR (297bp) and the polymerase domain of the RT(703bp). Both PCR and sequencing conditions have been described elsewhere  and treated subjects. Treated subjects group was further subdivided into three different subgroups according to length of exposure to ARV´s . Viral suppression bellow WHO cutoff was 92.5%, 96.3% and 87% for G2, G3 and G4, respectively. When undetectability of virus load was utilized as cutoff, a viral suppression of 85%, 90.1% and 76% was observed for the same groups, respectively. The theraputical failure measured by CD4 response did not agreed with individuals failing by virological parameters. In fact, there was a noticeable number of patients not increasing the CD4 counts after HAART initiation  showing undetectable VL in all treated groups analyzed . Of noteIn total, 68 sequences from naïve subjects with detectable viral load were sequenced (72.3%) and these mainly clustered with subtype C , with the occurrence of one B/D (1.47%) and one C/G (1.47%) mosaics. Similarly, a subtype C dominance was observed in sequences from subjects failing treatment with the occurrence of one sequence with subtype A (1.5%), one with subtype B (1.5%), as well a mosaic B/C (1.5%). We could also found one divergent sequence (1.5%) that could not be resolved by phylogenetic analysis(Data not shown). The overall prevalence of primary drug resistance based on WHO mutation list was 0%, 4.4% and 1.5% for NRTI, NNRTI and PI respectively.As previously reported for subtype C, the prevalence of second generation NNRTI mutation E138A/G/K (8.8%) and M230L (5.9%) was more prevalent when compared to subtype B counterpart. A collection of primary mutation in a range of 3 to 1% could be observed in RT most of all related to NNRTI resistance . We could also observe some polymorphic substitutions in drug resistance codons not associated to resistance. A lysine to asparagine substitution was observed at position 65 (K65N) of the RT with a high prevalence (10.4%). However this polymorphism was not associated to tenofovir (TDF) resistance. Other polymorphic sites in RT position 67, 69 and 151 could be observed although these are not related to resistance associated mutations RAMs; .The first-line option widely used in country was based on 3TC+d4T+NVP (87.1%) followed by 3TC+d4T+EFV (9.7%) and 3TC+AZT+EFV (3.2%). . MaximumA total of 36 (78%) sequences were successfully genotyped from a total of 46 with detectable viral load in ARV treated groups. Resistance profile of sequences from 17 subjects harboring at least ≥1 RAM are documented in Analysis of RAMs showed that 70.6% of the subjects harbored RAM´s associated to NRTIs and 84.1.% to NNRTIs. The most frequent NRTI and NNRTI mutations found were M184V (91.7%) and G190A (50%), respectively. TAMs were mainly seen in sequences from G4 , with one occurrence in G3 (25%). These TAMs were mainly belonged to TAM-2 pathway (83.3%). The most common NNRTI mutations observed were K103N/S and G190A. More complex RAM patterns were seen with increasing exposure to HAART. For example, in G4 there were sequences incorporating >3 NRTI mutations (20%), and in G3 and G4 there were sequences carrying >2 NNRTI mutations (50%) . Since aAnalysis of 17 sequences with RAMs profile showed a decrease in drug susceptibility to all approved RT inhibitors with an accentuated decrease to NRTI inhibitors 3TC and emtricitabine (FTC). Similarly, the genotypic resistance to abacavir (ABC) was observed in 70% of sequences analyzed however, resistance level ranged from potential low to intermediate level of resistance. Prediction of susceptibility to the remaining NRTI inhibitors showed that solely 20% of isolates decreased their response to AZT, d4T and DDI whereas the majority of sequences in this group remain susceptible to TDF (90%). Additionaly, the majority of samples analyzed shown a high level resistance to EFV and NVP and these isolates carry a complex pattern of NNRTI-RAM such as G190A, K103N, and Y181C. Due to this complex pattern, susceptibility to second generation NNRTIs, rilpivirine (RPV) and etravirine (ETR) showed some level of cross-resistance that ranged from potential low level to intermediate resistance based on Stanford HIVDB prediction algorithm .The present study shows the prevalence of RAM’s and the mutation profile in drug naive individuals in Mozambique and subjects failing HAART attending public health care services.Current treatment strategies have shown to be effective in treating HIV infection in Mozambique where the epidemic is dominated by subtype C, as reported previously . In fact3) to G4 (383 cells/mm3), an 92 cells/mm3 increase between these two groups. Nonetheless, this increase is bellow the values reported by Auld and colleagues on data from Mozambique where the mean gain was 186, 273 and 293 cell/mm3 for a HAART period of 24, 36 and 48 months respectively [3). The fact that this study used a cross-sectional approach may also justify such low increases observed [Our results suggest that maximum viral suppression is observed after 12 months even if we consider that our patients has initiated HAART severely immunocompromised. It was demonstrated that current drug regimens suggested by WHO for first-line treatment approach are effective in promoting immunological recovery as given by significant increase in median TCD4+ count from G2 . Of note, there is the low concordance between viral detectable VL and RAM in G2 that may result from high viral loads at the beginning of treatment and after 12 months on HAART the viral replication is still been suppressed. Drug resistance patterns were in accordance with the treatment options used in the country. High prevalence of mutation M184V reflects the wide use of 3TC. The occurrence of this mutation in early treatment groups may explain low prevalence of TAMs in these groups . TAMs weLow prevalence of primary drug resistance based on WHO mutation list was observed in our data set and this was consistent with results recently published by our group for the same geographic area, using the WHO threshold survey methodology. The dynamics of the epidemic differ across the southern, central and northern region of Mozambique. Recent data from our group have shown that primary RAM tend to show the same trend, with the central region exhibiting the highest prevalences (unpublished data). All together with the expansion of HAART program in the country indicate that efforts should be put in place to monitor the emergence of RAM in naïve subjects, as this may ensure the use of fully suppressive drugs in the country. Furthermore, constant evaluation of treatment program and gradual introduction of viral load to monitor treatment, at least in subjects exposed to HAART for longer, will ensure timely detection of treatment failures, preventing the occurrence of TDR and new infections. In vitro selection culture should be performed in order to generate data describing the outcome of viruses carrying mutation K65N with and without TDF.Of note, mutation T74S has been described as polymorphic in subtype C viruses circulating in Africa and South America, and it is associated with reduced nelfinavir susceptibility , here weS1 Fig(TIF)Click here for additional data file.S2 Fig(TIF)Click here for additional data file.


According to recent evidence about boosted protease inhibitors (PIs/r)-simplified regimens, the combination of 3TC and DRV/r 800/100 mg could represent a feasible option for optimizing antiretroviral therapy (ART) in treatment-experienced HIV+ patients.We retrospectively evaluated patients switching to 3TC+DRV/r, with at least six months of viral suppression, no resistance mutation to DRV or 3TC and not HBV-coinfected: incidence of ART discontinuation and of virological failure (VF: 2 consecutive HIV-RNA determinations>49 cps/mL or a single one≥1000 cps/mL) and the probability of remaining discontinuation-free during one-year follow-up (FU), as well as changes in laboratory parameters at 1, 3, 6 and 12 months were estimated.We included 94 patients: 74 males, mostly MSM (39.4%), with 49 years old, 9 years of HIV disease, 8 years of ART . Median nadir CD4 count and zenith viral load (log10) were 194 cells/µL and 4.90, respectively. Ten patients were HCV-coinfected and 38 had at least a previous VF. Seventy-four patients were on an NRTIs-based triple regimen (mainly TDF/FTC or 3TC/ABC) whereas 14 on another PI-based dual therapy (mainly LPV/r). Incidence of treatment discontinuation was 12.4 per 100 patients-year follow-up (PYFU), but only 2 patients experienced a VF (3.5 per 100 PYFU). Mean time free from discontinuation was 5 years (95% CI 4–6), with a cumulative one-year estimated probability of staying on 3TC+DRV/r of 85.9%. At three months, a trend of increased CD4 cells count  was observed, but not confirmed at later time point; an increase of total cholesterol  and LDL , and a decreased level of AST and ALT  were also detected. Total bilirubin was reduced . At 6 and 12 months, alteration of lipid profile was similar, with also an increased TC/HDL ratio  and HDL/LDL ratio . A significant decrease in ALT levels  and a diminishing trend for AST and total bilirubin, as well as a significant increase in renal function  were observed at 12 months.These observations on 3TC+DRV/r-based dual therapy simplification in virologically suppressed patients show a good profile of efficacy and safety. An extended FU time is needed in order to establish the real impact of this promising therapeutic choice.


Additionally, advanced HIV disease (AD) is defined by a CD4 count below 200 cell/mm3 or an AIDS defining condition in persons presenting to care.Late HIV diagnosis is common and associated with an increased risk of clinical progression, blunted immune response on antiretroviral (ARV) therapy and higher risk of drug toxicity. Across Europe, more than a third of patients are diagnosed late and consequently delay medical care. European Consensus definition group identify as late presentation (LP) persons, presenting for care, with a CD4 count below 350 cell/mmRetrospective observational study of a cohort of 705 HIV-infected patients diagnosed between 1986 and 2014 and medically followed at an Infectious Diseases Service in Lisbon.Evaluate LP rate evolution in the last three decades ; compare clinic, immunologic, virologic and therapeutic response over time. Identify main reasons responsible for late HIV diagnosis in order to promote optimized intervention strategies. SPSS version 20.0 was used for statistical analysis.3. Considering the time intervals, LP was found in 52% vs 56% vs 52% of patients and AD in 31% vs 38% vs 35%, respectively. At first health care encounter, 46% vs 43% vs 39% of individuals presented with AIDS. Over follow up, the vast majority initiated ARV (95% vs 98% vs 84%) and mean CD4 at that time was 254 vs 282 vs 250 cell/mm3. The last immunologic and virologic determination available registered mean CD4 of 657 vs 644 vs 584 cell/mm3 and undetectable HIV plasma RNA in 92% vs 84% vs 82% of treated patients.Study included 705 patients HIV diagnosed during 3 time intervals: group A n=82 [1986–1995]; group B n=332 [1996–2005]; group C n=291 [2006–2014]. Demographic and epidemiological characterization revealed (A vs B vs C): male predominance of 79% vs 66% vs 66%; mean age at diagnosis 30 vs 36 vs 42 years; Portugal (82% vs 70% vs 58%) and Africa (13% vs 23% vs 29%) as the main places of birth; transmission by heterosexual contact in 21% vs 47% vs 62%, MSM in 21% vs 15% vs 23% and IVDU in 57% vs 35% vs 13%. Mean CD4 at diagnosis was 362 vs 344 vs 377 cell/mmThis study evidenced a maintained LP rate, slightly above 50% in each of the three analyzed last decades, and one-third of patients presented AD at HIV diagnosis. At initial health care contact, nearly 40% of individuals met AIDS clinical or immunological criteria.


The integrase (IN) strand transfer inhibitors (INSTIs), raltegravir (RAL), elvitegravir (EVG) and dolutegravir (DTG), comprise the newest drug class approved for the treatment of HIV-1 infection, which joins the existing classes of reverse transcriptase, protease and binding/entry inhibitors. The efficacy of first-line regimens has attained remarkably high levels, reaching undetectable viral loads in 90% of patients by Week 48; however, there remain patients who require a change in regimen due to adverse events, virologic failure with emergent resistance or other issues of patient management. Large, randomized clinical trials conducted in antiretroviral treatment-naive individuals are required for drug approval in this population in the US, EU and other countries, with the primary endpoint for virologic success at Week 48. However, there are differences in the definition of virologic failure and the evaluation of drug resistance among the trials. This review focuses on the methodology and tabulation of resistance to INSTIs in phase 3 clinical trials of first-line regimens and discusses case studies of resistance. The treatment of many patients infected with HIV-1 has become relatively straightforward for first-line regimens based on international treatment guidelines. The most recent class of HIV-1 inhibitors to be approved target the HIV-1 integrase (IN) gene via the inhibition of the strand transfer step: IN strand transfer inhibitors (INSTIs) .Approval of an HIV drug in treatment-naive individuals requires the rigorous testing of the drug alone and in combination with other inhibitors through the clinical development process across phase 1, 2 and 3 studies. The final phase of the drug development process prior to submission for review and approval by regulatory bodies are the large, randomized, double-blind, phase 3 studies . In thisMajor guidelines for the treatment of HIV-1-infected patients provide recommendations for when to treat, what to treat with and how to monitor for virologic failure. The most influential guidelines are the United States Department of Health and Human Services (DHHS), International Antiviral (formerly AIDS) Society-United States of America (IAS-USA), European AIDS Clinical Society (EACS), World Health Organization (WHO) and the British HIV Association (BHIVA) ,7,8,9,10l regimens and not all have been updated to include the INSTI class in first-line therapy. All guidelines recommend a nucleos(t)ide reverse transcriptase inhibitor (NRTI) backbone typically consisting of a fixed-dose combination of either emtricitabine and tenofovir disoproxil fumarate (FTC/TDF) or abacavir and lamivudine (ABC/3TC). For the third agent, other antiretroviral classes, including non-nucleoside reverse transcriptase inhibitors (NNRTIs) or ritonavir-boosted protease inhibitors (PIs), are recommended, but here, we will focus on the INSTI class. For the use of INSTIs as the first line, the DHHS includes all three INSTIs as recommended first line regimens: RAL + FTC/TDF, EVG/COBI/FTC/TDF (the single tablet regimen of cobicistat (COBI)-boosted EVG with FTC/TDF), DTG + ABC/3TC and DTG + FTC/TDF [The guidelines also differ in their choice of “recommended” antiretrovira FTC/TDF ,9. The I FTC/TDF . The EAC FTC/TDF . The BHI FTC/TDF . The WHO FTC/TDF .The definition of virologic failure and when to change to a second-line regimen also vary between guidelines. The DHHS guidelines define virologic failure and recommend resistance testing for visits with HIV-1 RNA >1000 copies/mL (after having achieved virologic suppression) and suggest considering resistance testing at viral loads between 500 and 1000 copies/mL ,9. The B In vitro resistance selections found that primary mutations can emerge rapidly in tissue culture. In vivo, INSTI resistance can also rapidly occur in patients treated with RAL or EVG when not supported by a fully-active, two-drug backbone [The INSTIs have potent antiviral activity. All currently approved INSTIs are small molecules that share key chemical motifs and bind to the active site of IN ,11,12. Tbackbone ,16. The backbone . In developed countries, it is standard to conduct HIV-1 genotyping prior to starting the first antiretroviral regimen. This is important because an estimated 10%–15% of treatment-naive patients harbor primary drug resistance mutations in the PR and RT coding regions of the pol gene . Because® HIV-1 RNA 3.0 assay ), and <50 copies/mL using the COBAS Amplicor HIV-1 Monitor Test, version 1.5 (Roche Diagnostics). Presently, real-time PCR approaches have further lowered the limit of detection to 40 copies/mL using the Abbott RealTime HIV-1 PCR assay [Clinical trials of HIV-1 utilize the plasma HIV-1 RNA concentration, referred to as the viral load, as the primary biomarker of antiviral drug efficacy. International guidelines recommend targeting an undetectable viral load. In the first decade of clinical trials of HIV-1, the viral load target was set to achieving <400 copies/mL, which was the lower limit of detection of the assays available at the time. The lower limit of detection for viral load assays has been subsequently improved. A viral load detection limit of <75 copies/mL was achieved using the branched DNA (bDNA) assay  plus FTC/TDF [n = 241/280) of the RAL group achieved the primary endpoint of <50 copies/mL of HIV-1 RNA at Week 48, compared with 82% (n = 230/281) of the EFV group , indicating that RAL was non-inferior to EFV (p < 0.0001 for non-inferiority) [n = 318/382) in the QD group compared with 89% (n = 343/386) in the BID group had HIV-1 RNA <50 copies/mL . The once-daily dosing was to be regarded as non-inferior to twice-daily dosing if the lower bound of the 95% CI for the difference was above −10%; therefore, the reported, one-sided p = 0.44 failed to show non-inferiority. Based on this data, the once-daily RAL dose was not recommended. Two studies evaluated RAL as the first-line therapy. STARTMRK was an international, double-blind, phase 3 randomized trial comparing 400 mg RAL twice a day plus FTC/TDF FTC/TDF . At Weekriority) . The QDM82% n = 2/281 of t vs. EFV/FTC/TDF [n = 305/348) in the EVG group compared to 84% (n = 296/352) in the EFV group . Study GS-US-236-0103 was a phase 3, randomized, double-blind study conducted in Australia, Europe, North America and Thailand of EVG/COBI/FTC/TDF compared to ritonavir-boosted atazanavir (ATV + RTV) plus FTC/TDF [n = 316/353) in the EVG group compared to 87% (n = 308/355) in the ATV + RTV group . These EVG studies concluded the non-inferiority of EVG/COBI/FTC/TDF compared to EFV/FTC/TDF or ATV + RTV + FTC/TDF. Two phase 3 studies evaluated the EVG-based EVG/COBI/FTC/TDF regimen as a first-line therapy. In both studies, the primary endpoint was an HIV-1 RNA concentration of <50 copies/mL at Week 48 by intention-to-treat , with a 12% non-inferiority margin. Study GS-US-236-0102 was a phase 3, randomized, double-blind study conducted in North America of EVG/COBI/FTC/TDF/FTC/TDF . At Week FTC/TDF . At Weekn = 361/411) in the DTG group, compared with 85% (n = 351/411) in the RAL group , indicating that DTG was non-inferior to RAL [n = 364/414) in the DTG group, compared with 81% (n = 338/419) in the EFV group , indicating that DTG met the non-inferior margin and, in a pre-planned secondary analysis, was superior to EFV (p = 0.003), driven by differences in discontinuations due to adverse events [ vs. ritonavir-boosted darunavir (DRV + RTV) plus FTC/TDF or ABC/3TC [n = 217/242) of the DTG group achieved viral load <50 copies/mL vs. 83% (n = 200/242) of the DRV + RTV group  and was non-inferior [p = 0.025), primarily driven by higher discontinuations in the DRV group [Three phase 3 studies have been conducted with DTG in treatment-naive patients. In these studies, the primary endpoint was an HIV-1 RNA concentration of <50 copies/mL at Week 48 by intention-to-treat  ,34,35. Sr to RAL . SINGLE Clinical trial protocols require formal descriptions of the criteria for the inclusion of a patient into the resistance analysis population (RAP). Guidelines require that plasma is collected and stored for later analyses of the development of resistance mutations. Generally, the specific samples to be analyzed are prospectively defined to adequately describe resistance development and provide for patient management. However, the choice of which sample(s) to study is not standardized between guidelines or between pharmaceutical companies. Within the development program of a drug, the resistance analyses may differ to fit the objectives of each particular study or phase of development. This is also an area of debate in routine clinical settings and is subject to budgetary limitations at hospitals, clinics, insurance companies and governments. In clinical trials and clinical practice, a variety of commercial and hospital-based assays are used for genotyping and phenotyping samples for HIV-1 drug resistance. Monogram Biosciences provided the resistance testing for IN in all of the trials reviewed here. The Monogram assay for PR and RT has been available for many years  and is nThe seven INSTI protocols utilized a variety of definitions for the resistance analysis population . The RAP10 decrease from baseline and ≥50 copies/mL by Week 8 and confirmed at the Week 12 visit. Virologic rebound was confirmed HIV-1 RNA ≥400 copies/mL after achieving <50 copies/mL or having two consecutive visits with ≥1 log10 increase in HIV 1 RNA from nadir. Virologic rebound required a confirmation unless the rebound occurred at Week 48, early study drug discontinuation or the last visit. The confirmed virologic failure sample, if available, was analyzed. Patients were allowed to continue in the study and on study drugs at the discretion of the investigator until emergent resistance was reported, and thus, additional later samples were tested in some cases.The definition of the RAP was identical in the EVG studies GS-US-236-0102 and GS-US-236-0103 ,32. All The RAP was similar for both SPRING-2 and SINGLE and consisted of patients who had protocol-defined virologic failure between Week 24 and Week 48 ,34. Prot vs. the second virologic failure sample, the timeframe of inclusion in the resistance analysis population, the viral load criteria for resistance testing and protocol-specified discontinuation requirements.There is a lack of standardization between approaches to study resistance development and how to manage patients with virologic failure. The similarities between these studies are that samples are collected and stored for analysis, and the assays used to study viral load and emergent drug resistance are similar. Differences that can lead to significantly discordant patient virologic outcome are the analysis of the firstIn most cases during the development of a drug, resistance analyses consist of genotyping (sequencing) the HIV-1 viral gene coding regions targeted by the drug and phenotyping against the drug and a panel of other inhibitors. In the cases of the INSTI studies described here, resistance and cross-resistance to the INSTIs that were approved at the time of study were evaluated. The specific sample analyzed, such as the first above a viral load threshold, the confirmatory sample and/or subsequent samples, differs between studies and within clinical practice. Most analyses in these clinical trials utilized similar assays for virologic failure sample analysis. Through Week 48, emergent resistance to the INSTI, other class and NRTI backbone is described . In the Resistance in the RAL studies was infrequent and often consisted of both INSTI and NRTI resistance mutations. Through Week 48 of STARTMRK, the HIV-1 from nine patients was analyzed for resistance development in the RAL group. Of these, eight of nine samples had genotypic information available for IN, and four patients had emergent INSTI resistance mutations  . In the Resistance in the EVG studies was also infrequent and consisted of INSTI-R and NRTI-R in most cases. Through Week 48 in Study GS-US-236-0102, there were 14 patients analyzed for resistance in the EVG/COBI/FTC/TDF group, and all had data available for RT and IN. Eight patients (2.3% of the randomized population) had emergent resistance to a study drug . Seven pn = 2; V151I, n = 1; E138T/A + T97A with preexisting Q148H, n = 1) [ in vivo resistance pathways for DTG in treatment-naive patients will require further study and might be observed in patients who are maintained for more extended periods on a failing regimen. In the clinical studies of DTG, treatment-naive patients were rapidly discontinued from study per protocol upon confirmation of >50 copies/mL of HIV-1 RNA, which prevented extended virologic failure on the treatment.The DTG treatment-naive patient studies reported no emergent resistance in any of the INSTI-containing arms of the studies. Through Week 48 in the SPRING-2 study, the HIV-1 from 20 patients was analyzed for resistance development in the DTG group and from 28 patients in the RAL group . The res, n = 1) . Given tTo illustrate some of the differences between inclusion in the resistance analysis population and patient management by the different protocols of INSTI trials in treatment-naive patients, clinical cases from the GS-US-236-0102 and GS-US-236-0103 studies are presented and discussed . Most caCase 1 is a typical example of the rapid virologic suppression achieved by an INSTI-based regimen . This is10 copies/mL by Week 4. At Week 4, the patient was given a 30-day supply of study drugs. He missed his Week 8 visit, but returned for his Week 12 visit and had a viral load comparable to baseline , consistent with non-adherence, due to running out of study medication. At the Week 12 visit, the patient in Case 2 was given another 30-day supply of study drugs, but upon a Week 12 retest visit 11 days later, the viral load was still high at 63,400 copies/mL. Subsequently, the viral load decreased to 3820 at Week 16 and was <50 copies/mL at Week 24 through Week 48.Case 2 is an example of a patient with initial suboptimal virologic response followed by virologic suppression. This is a 54-year-old male with a baseline HIV-1 RNA of 69,500 copies/mL, who was randomized and treated with EVG/COBI/FTC/TDF and had a weak virologic response of −0.62 logThe patient in Case 2 had a suboptimal virologic response by the EVG protocols, and the suboptimal virologic response failure confirmation sample (Week 12 retest) was sent for genotypic and phenotypic resistance testing. No resistance mutations were found in the HIV-1 RNA from the Week 12 retest sample. EVG/COBI/FTC/TDF was continued successfully through Week 48. According to the RAL and DTG protocols, because the viral load was <50 copies/mL at Week 24, no sample would have been analyzed for resistance. In the RAL and DTG protocols, Case 2 would be considered a virologic success, while in the EVG protocols, he was counted in the resistance analysis population, but was a virologic success at Week 48.Case 3 is an example of a patient with viral load suppression followed by a virologic rebound to ≥400 copies/mL that was confirmed at the next visit. Virologic rebound and confirmation of rebound occurred prior to Week 24. This is a 37-year-old female with a baseline HIV-1 RNA of 107,000 copies/mL, who was randomized and treated with EVG/COBI/FTC/TDF and had an initial viral load response of <50 copies/mL achieved at Week 4 and confirmed at Week 8. At Week 12, the viral load was found to be 5410 copies/mL, which remained elevated at Week 16 (1190 copies/mL) and at Week 24 (2840 copies/mL). Case 3 was considered a virologic rebound by the EVG protocols and had the failure confirmation sample (Week 16) sent for genotypic and phenotypic resistance testing. By the RAL protocols, virologic rebound to >400 copies/mL was confirmed, and the Week 12 sample would have been tested. If this showed no mutations, then the Week 16 sample would also have been sent for resistance testing. If resistance was found, then this patient would have been discontinued at a later visit, at the discretion of the Investigator. According to the DTG protocols, the rebound occurred prior to Week 24, and no sample would have been sent for resistance testing, unless the rebound was confirmed on or after the Week 24 visit window. The DTG protocols required a confirmation visit within 1–4 weeks after the suspected virologic failure. In this case, this next visit would have confirmed the virologic failure, and the Week 24 sample would have been sent for resistance testing. It is also possible that the patient in Case 3 could have been discontinued prior to Week 24, in which case, no sample would be analyzed for the emergence of resistance  for emergent resistance. Post hoc analysis of the first failure Week 24 sample found M184V in RT and no mutation in IN. An additional post hoc analysis of the discontinuation visit sample from Week 40 by clonal sequencing found clones with four main resistance patterns: M184V + Q148R, M184V + E92Q, M184V + N155H, and M184V alone [Resistance mutations in RT and IN were detected in the Week 32 sample , and the patient was discontinued due to lack of efficacy at the Week 40 visit once the results were obtained. 4V alone . Case 4 4V alone . Patient management would have been different by these protocols. By the EVG protocols, the patient from Case 4 was to be discontinued as soon as the resistance results showing resistance mutations to a study drug were obtained, as was done in this case. By the RAL and DTG protocols, Case 4 would have been brought back in for a viral load retest (within 1–4 weeks after the Week 24 suspected virologic failure visit for the DTG protocols) and discontinued if the confirmation result was >50 copies/mL for SPRING-2 and SINGLE and if >200 copies/mL for FLAMINGO, which was satisfied by the data available at Week 32. The decision to discontinue the patient was made by the investigator for the RAL protocols, but likely would have been as soon as resistance was detected. Based on population sequencing data and more rigorous retest/return visits required by the RAL and DTG protocols, the development of resistance mutation in the IN gene may have been prevented. Case 5 is an example of a patient with viral load suppression followed by an extended period of low-level viremia with virologic success of HIV-1 RNA <50 copies/mL at Week 48. This is a 42-year-old male with a baseline HIV-1 RNA of 315,000 copies/mL, who was randomized and treated with EVG/COBI/FTC/TDF. He had an initial viral load response, and a viral load of <50 copies/mL was first achieved at Week 16 and was confirmed at Week 24. At Week 32, a low-level viremia of 77 copies/mL was first detected, and the low-level viremia continued through Week 48. After Week 48, a retest was performed and showed HIV-1 RNA <50 copies/mL. By the DTG protocols of SPRING-2 and SINGLE, Case 5 would be a virologic rebounder. The suspected virologic failure sample  would have been analyzed, and this patient would have been discontinued at the next visit. The FLAMINGO protocol required rebound viremia to exceed 200 copies/mL, and therefore, Case 5 would not be considered a virologic rebound. The RAL protocols would not have categorized Case 5 as a having had a rebound, because the last value in the Week 48 window was <50 copies/mL. By the EVG protocols, Case 5 was not considered to have a rebound, because the viral load was not ≥400 copies/mL at two consecutive visits. The patient in Case 5 continued their blinded EVG/COBI/FTC/TDF treatment and had HIV-1 RNA <50 copies/mL at all subsequent study visits from Week 48 through Week 144.Case 6 is an example of a patient with viral load suppression followed by a virologic rebound. This was a 42-year-old male with a baseline HIV-1 RNA of 273,000 copies/mL, who was randomized and treated with EVG/COBI/FTC/TDF. This patient had an initial viral load response, and a viral load of <50 copies/mL was first achieved at Week 8, followed by transient low-level viremia and resuppression at Week 24. At Week 40, there was a viral load rebound to 15,800 copies/mL that was followed by persistent, low-level viremia and HIV-1 RNA >400 copies/mL at Week 60 that was confirmed at Week 72.By all protocols, Case 6 would be considered a virologic rebound; however, the time at which the failure was confirmed and tested for emergent resistance would vary by protocol. The DTG protocols would have led to the earlier testing of Case 6 at Week 40 for SINGLE and SPRING-2 after two consecutive visits with >50 copies/mL. The Week 48 sample would have had resistance testing by FLAMINGO, being the first failure sample of two consecutive visits with >200 copies/mL. The RAL and EVG protocols required a higher viral load for testing. The RAL protocols would have analyzed the first sample with >400 copies/mL at Week 60, and the EVG protocols analyzed the confirmation sample with viral load ≥400 copies/mL at Week 72. Post hoc analysis of the first failure Week 40 sample found no mutations in RT or IN. Case 6 is a good example of the most frequently occurring pathway of resistance to EVG/COBI/FTC/TDF of M184V/I + E92Q and is similar to the combination resistance of M184V/I plus INSTI-R in RAL + FTC/TDF virologic failures [For Case 6, resistance mutations in RT and IN were detected in the Week 72 sample (M184V in RT and E92Q in IN), and the patient was discontinued due to lack of efficacy at the Week 72 retest visit once the results were obtained. failures ,30,31,32Patient management would have been different by these protocols. By the EVG and likely the RAL protocols, the patient in Case 6 was to be discontinued as soon as the resistance results finding resistance to study drugs were obtained, as was done for this patient. By the DTG protocols, this patient would have been brought back in for a viral load retest within 1–4 weeks after the Week 40 suspected virologic failure, which did occur, and discontinued if the result was >50 copies/mL for SPRING-2 and SINGLE (Week 40 retest) and if >200 copies/mL for FLAMINGO (Week 48 retest). Based on population sequencing of the Week 40 sample, the emergence of resistance was not detected. The requirement for a higher viral load at virologic failure may have led to the longer treatment of this patient on a failing regimen, and the earlier change in therapy may have limited the emergence of resistance mutations in both RT and IN. However, several cases of confirmed rebound and no emergent resistance followed by sustained suppression were also observed, as will be described in Case 8.10 copies/mL by Week 2. At Week 24, the viral load was 96 copies/mL. Low-level viremia was reported at Weeks 32 and 40 of 252 copies/mL and 185 copies/mL, respectively. At Week 48, the viral load was <50 copies/mL for the first time.Case 7 is an example of a patient with slow viral load suppression that took until Week 48 to reach a viral load of <50 copies/mL. This is a 52-year-old female with a baseline HIV-1 RNA of 346,000 copies/mL, who was randomized and treated with EFV/FTC/TDF, had an initial viral load response greater than 1 log10 decrease in viral load by Week 8 and did not have a rebound to >1 log10 from nadir, or two consecutive ≥400 copies/mL viral loads, the EVG protocols would also not call for resistance testing or patient discontinuation. The FLAMINGO protocol would not call for resistance testing, because the viral load was not >200 copies/mL at two consecutive visits. According to the DTG protocols (with the exception of FLAMINGO), since the HIV-1 RNA was >50 copies/mL at Week 24 and confirmed at the next visit, a resistance test would have been conducted on the Week 24 sample, and the patient in Case 7 would be discontinued after the Week 32 visit . Since this patient was suppressed at Week 48, there would have likely been no resistance, and this patient would have been discontinued and considered a virologic failure, while in the FLAMINGO, as well as in the EVG and RAL protocols, this patient was considered as a virologic success.Case 7 would have been managed differently by the INSTI clinical protocols. Since the viral load was <400 copies/mL and was undetectable at Week 48, the RAL protocols would not call for resistance testing or patient discontinuation. Because the virus had >1 logCase 8 is an example of a patient with viral load suppression followed by confirmed virologic rebound to viral load ≥400 copies/mL, no evidence of emergent resistance, followed by resuppression and virologic success at Week 48. This is a 22-year-old female with a baseline HIV-1 RNA of 14,900 copies/mL who was randomized and treated with EVG/COBI/FTC/TDF. A viral load <50 copies/mL was first achieved at Week 2 and maintained through Week 8. At Week 12, the viral load was 5080 copies/mL, and the viral load rebound was confirmed at Week 16, with 4600 copies/mL. At Week 16, a retest measured the viral load at 51 copies/mL, followed by <50 copies/mL at all subsequent visits through Week 48. Case 8 would be managed differently by the INSTI protocols. The EVG studies considered Case 8 a virologic rebound and sent the failure confirmation sample (Week 16) for genotypic and phenotypic resistance testing. No resistance to study drugs was found, and the patient continued on study drugs and was considered a virologic success at Week 48. According to the RAL and DTG protocols, the rebound occurred prior to Week 24 (DTG protocols) or the patient resuppressed (RAL protocols), and no sample would have been analyzed for resistance. Current initial treatments for HIV-1 infection are highly effective, have good safety profiles and are generally well tolerated. As antiretroviral drugs have improved in potency and tolerability, combined with the greater simplicity of the newest combinations, such as the single-tablet regimens, adherence is facilitated and the frequency of virologic failure and emergent resistance has declined. Nevertheless, emergent resistance can occur, which can compromise the activity of ongoing regimens under the selective pressure of persistent viremia and limit the remaining choices for future therapy. Thus, characterization of the resistance profile of a new drug through clinical development continues to be critical. Moreover, the development of new classes of antiretrovirals with high resistance barriers that do not overlap with other drug classes is still needed. In addition, with the high rate of efficacy currently achieved of up to 90% and more sensitive assays for the detection of low-level viremia and minority resistance variants, the choice of study design and the resistance analysis plan is important, so that the best information on future clinical care is obtained.There remain many questions regarding resistance analyses and virologic failure, such as which genes to sequence prior to therapy, which viral load signifies virologic failure, which samples to test for resistance and when to change a failing regimen. Furthermore, standards will vary among clinical trials, clinical practice and by region. Resistance testing at failure for the EVG studies was performed on confirmed virologic failure samples with HIV-1 RNA ≥400 copies/mL. For the RAL studies, testing was performed at the first failure with HIV-1 RNA >400 copies/mL, while in SPRING-2 and SINGLE, genotyping was performed on the first sample from virological failures at or after Week 24 with HIV-1 RNA >50 copies/mL. Such differences between study protocols limit cross-study comparison, as the resistance data generated depends on the resistance analysis time point, which may allow for periods of low or intermediate viral replication prior to analysis. Indeed, conducting a genotypic test on the first sample above 50 copies/mL does not provide the same information as a genotype confirmatory sample ≥400 copies/mL, the latter situation being the one most often followed in clinical practice.In the seven phase 3 clinical trials of INSTI-based regimens as a first-line therapy presented here, high efficacy outcomes were observed in the absence of pre-treatment genotypic information for the IN gene ,33,34,35The definition of what viral load constitutes virologic failure also continues to be debated and will likely depend on the regimen. Intense discussion on patient management in the setting of low-level viremia and the risk of virologic failure are also ongoing ,47. ViroIn this review, seven major randomized and controlled clinical trials of INSTI-based initial treatment of HIV-1 infection showed high efficacy outcomes. The rate of resistance remains low for first generation INSTIs and has, to date, been absent for DTG in treatment-naive patients. However, differences in clinical protocols and resistance testing may have contributed to some of the differences in the study and resistance outcomes among these trials. These differences underscore the challenges in comparing the resistance profiles of new drugs characterized in different clinical development programs. Greater consistency in approaches to resistance analyses will help; however, evolving clinical standards and assays will likely hinder universal conformity. The INSTI class has been the most recently introduced class of antiretroviral drugs and has shown strong efficacy and safety. INSTI-based regimens are now providing for another highly-effective therapeutic option for HIV-1-infected patients.


To determine the prevalence of adequate monitoring and the costs of measuring CD4+ T-lymphocytes (CD4+ cell) and human immunodeficiency virus (HIV) viral load in people receiving antiretroviral therapy (ART) in seven countries in the WHO Region of the Americas.We obtained retrospective, longitudinal data for 14 476 adults who started a first ART regimen at seven HIV clinics in Argentina, Brazil, Chile, Haiti, Honduras, Mexico and Peru between 2000 and 2011. We estimated the proportion of 180-day periods with adequate monitoring, which we defined as at least one CD4+ cell count and one viral load measurement. Factors associated with adequate monitoring were analysed using regression methods. The costs of the tests were estimated.The median follow-up time was 50.4 months; the proportion of 180-day periods with adequate CD4+ cell counts was 69% while the proportion with adequate monitoring was 62%. Adequate monitoring was more likely in participants who were older, who started ART more recently, whose first regimen included a non-nucleoside reverse transcriptase inhibitor or who had a CD4+ cell count less than 200 cells/µl at ART initiation. The cost of one CD4+ cell count ranged from 7.37 United States dollars (US$) in Argentina to US$ 64.09 in Chile; the cost of one viral load measurement ranged from US$ 20.34 in Brazil to US$ 186.28 in Haiti.In HIV-infected participants receiving ART in the WHO Region of the Americas, CD4+ cell count and viral load monitoring was often carried out less frequently than regional guidelines recommend. The laboratory costs of monitoring varied greatly. For people living with human immunodeficiency virus (HIV) who are receiving combination antiretroviral therapy (ART), the most important predictors of treatment outcomes are CD4+ T-lymphocyte (CD4+ cell) count and HIV load in the blood.2The number of people receiving ART and the cost of treatment are expected to increase in the future because of the worldwide trend to initiate ART at higher CD4+ cell counts and earlier identification of HIV-infected individuals. Improvements in life expectancy resulting from expanded ART programmes are also thought to increase costs.We used retrospective, longitudinal data routinely collected during clinical care and held by the Caribbean, Central and South America Network for HIV Epidemiology (CCASAnet),Box 1Fundación Huésped, Buenos Aires, Argentina.Instituto de Pesquisa Clinica Evandro Chagas, Fundacão Oswaldo Cruz, Rio de Janeiro, Brazil.Fundación Arriarán, Santiago, Chile.Le Groupe Haitien d'Etude du Sarcome de Kaposi et des Infections Opportunistes, Port-au-Prince, Haiti.Instituto Hondureño de Seguridad Social and Hospital Escuela, Tegucigalpa, Honduras.Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.Instituto de Medicina Tropical Alexander von Humboldt, Lima, Peru.The follow-up period after ART initiation was divided into 180-day periods; follow-up ended on the day of the last recorded visit or when death occurred. Participants were defined as being lost to follow-up if they had not visited the clinic in the 12 months before the database closing date of 1 January 2012. For the primary analysis, treatment monitoring was defined as adequate if at least one CD4+ cell count and one viral load measurement had been made in each 180-day follow-up period. The site in Haiti did not measure viral load during the study period and was not included in the primary analysis. However, the Haitian site was included in a secondary analysis, in which we defined adequate monitoring using the CD4+ cell count alone .The primary study outcome was the proportion of 180-day periods during which there was adequate monitoring. Any remaining follow-up time that did not fit within a 180-day period was ignored. For example, if a participant was followed for 400 days, two 180-day periods were included in calculating the proportion of follow-up with adequate monitoring; the remaining 40 days were not included. However, the remaining follow-up periods were included in sensitivity analyses as additional periods. The CD4+ cell count at ART initiation was defined as the measurement closest to the start of ART, but no more than 180 days before or 7 days after the start, and was categorized as either less than 200, 200–350 or more than 350 cells/µL. A participant was described as having had an AIDS-defining event before ART initiation if they had clinical disease that could be classified as Centers for Disease Control and Prevention category C or WHO stage IV. Combination antiretroviral therapy was defined as: (i) therapy based on a non-nucleoside reverse transcriptase inhibitor (e.g. one non-nucleoside reverse transcriptase inhibitor plus two nucleoside reverse transcriptase inhibitors); (ii) protease inhibitor-based therapy, including treatment with one ritonavir-boosted or unboosted protease inhibitor plus two nucleoside reverse transcriptase inhibitors; (iii) triple nucleoside reverse transcriptase inhibitor regimens; or (iv) any other regimen containing at least three drugs. Data were collected at each study site and entered into the database at the local level using codes that did not identify individual participants. Thereafter, data were sent for harmonization to the CCASAnet data coordinating centre at Vanderbilt University, Nashville, United States of America. The coordinating centre also carried out data quality checks and on-site audits to ensure data accuracy. Ethical approval was obtained from institutional review boards at each study site and at Vanderbilt University.Wall Street Journal for Argentina, Brazil, Chile, Mexico and PeruParticipant-level factors associated with the frequency of monitoring were identified using Poisson regression: the number of 180-day periods with adequate monitoring was the outcome and the total number of 180-day periods was the offset. A quasi-Poisson estimation procedure was used. Multivariable models included age, sex, CD4+ cell count at ART initiation, year of ART initiation, prior AIDS-defining events and the first ART regimen. Missing data on the CD4+ cell count and prior AIDS-defining events were imputed using multiple imputation with 10 replications. The rate ratio for adequate monitoring was computed for each site and the combined rate ratio across all sites was estimated using random effects meta-analysis. The costs of measuring the CD4+ cell count and viral load were obtained for each site in 2014 in the local currency. Costs were subsequently converted to United States dollars (US$) using exchange rates from the A total of 14 476 participants at the study sites met inclusion criteria: 1285 from Argentina, 2446 from Brazil, 1080 from Chile, 5696 from Haiti, 789 from Honduras, 772 from Mexico and 2408 from Peru. The characteristics of the sites, their sources of funding and the approximate cost of laboratory measurements at each site are summarized in P = 0.71) or the frequency and cost of viral load measurements .The frequency and cost of CD4+ cell counts and viral load measurements varied according to the study site . The medThe adequacy of CD4+ cell count and viral load monitoring is shown for each site in Factors associated with adequate CD4+ cell count and viral load monitoring at each site and across all sites combined were identified. At all sites, adequate CD4+ cell count and viral load monitoring was more likely in older participants  and in tFactors associated with adequate CD4+ cell count monitoring alone were also identified. Again, adequate monitoring was more likely in older participants  and in tWe found that HIV-infected people starting ART at seven sites in the region were monitored less frequently than recommended by regional and national clinical guidelines. On average, CD4+ cell count and viral load monitoring were done at least once every six months for only 62% of the time participants were in care, although the proportion varied greatly across sites. The equivalent proportion for CD4+ cell count monitoring alone was 69%. Adequate monitoring of both parameters was associated with older age at ART initiation, receiving ART in more recent years, starting ART when the CD4+ cell count was less than 200 cells/µL and a first ART regimen that included a non-nucleoside reverse transcriptase inhibitor.The annual cost of CD4+ cell count and viral load monitoring per participant varied greatly between countries. For instance, the annual cost of CD4+ cell count monitoring per participant in Mexico was around four times the median cost in the region and almost nine times the cost in Honduras. Although we are not aware of previous studies of the cost of monitoring ART efficacy in the region, the Pan American Health Organization (PAHO) recently noted that the annual cost of ART medications per participant in the most expensive countries was approximately 10 times that in the lowest-cost countries.19The implications of the variability in monitoring costs across the region we observed are difficult to discern. For instance, although it appears that the cost of CD4+ cell count and viral load monitoring at individual sites was not related to the frequency of monitoring or to adherence to guideline recommendations, we were not able to assess how cost differences affected participant care, such as the ability to detect treatment failure. Furthermore, it would be difficult to use our results to identify a single initiative that could reduce costs across the region because each centre itself negotiates costs and budgets with local laboratories and with different sponsors. For the large centres in Argentina, Brazil, Chile and Peru, it may be possible to reduce costs by exploiting the large demand to leverage services. However, this strategy may not work for centres in Haiti, Honduras or Mexico, where government and international funding agencies, or the local infrastructure, may restrict their ability to negotiate costs locally.The frequency of CD4+ cell count and viral load monitoring we observed in HIV-infected persons receiving ART was very similar to that reported in the region by PAHO.The low level of adherence to clinical guidelines we observed was probably due to a combination of factors related to the participants, physicians and other health-care providers and, more generally, to structural and programmatic characteristics. At the individual level, our findings agree with those of previous studies in identifying older age as an important factor associated with adherence to ART,Although we were not able to evaluate structural and programmatic characteristics in detail, we observed several factors that could explain some of the differences in monitoring between sites. For example, the Global Fund to Fight AIDS, Tuberculosis and Malaria did not cover the cost of viral load measurements in Haiti and, consequently, this test was little used. Haiti and Honduras have generalized HIV epidemics, whereas in the rest of the region HIV infection is concentrated among men who have sex with men and injection-drug users.Our study has several limitations. First, we used a conservative definition of adequate CD4+ cell count and viral load monitoring – six months is currently the maximum time interval recommended by the guidelines used at all sites and most countries in the region recommend measurements every three to four months.In conclusion, adherence to recommended CD4+ cell count and viral load monitoring frequencies was generally poor in the region, with large variations between sites. Laboratory costs were also highly variable. Further research is needed to identify the underlying cause of differences in the frequency and cost of monitoring across the region and studies should be carried out to evaluate the impact of less frequent laboratory monitoring on health outcomes in HIV-infected persons receiving ART. We hope our study findings will be helpful for developing and implementing HIV treatment guidelines.


The objective of this analysis is to perform an indirect comparison of elvitegravir, cobicistat, emtricitabine and tenofovir DF (E/C/F/TDF) to abacavir/lamivudine and dolutegravir (ABC/3TC + DTG) by using 2 trials evaluating each of these regimens in comparison to efavirenz, emtricitabine and tenofovir DF (EFV/FTC/TDF).An indirect comparison was performed by using a generalization of Bucher's methodology to calculate risk differences. Two phase III clinical trials (GS-US-236-0102 and SINGLE—described above) were used.95% = ). There was no statistically significant differences in the risk difference for serious adverse events ), drug related adverse event ), drug related serious adverse event ) and death ), respectively, between E/C/F/TDF and ABC/3TC + DTG. A significant difference was found for discontinuation due to adverse events with a higher rate for E/C/F/TDF ). There was also no statistically significant risk difference of the viral resistance of 1.2%  between E/C/F/TDF and ABC/3TC + DTG at week 48, 1.7% at week 96  and 2.2%  at week 144.Results of the indirect comparison showed no statistically significant risk difference of the efficacy endpoint of achieving HIV RNA < 50 copies/mL between E/C/F/TDF and ABC/3TC + DTG for the ITT population at weeks 48, 96 and 144: respectively -3.7% , -5.2%  and -3.1% (CI According to the Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents of the Department of Health and Human Services the initial antiretroviral therapy (ART) should combine two nucleos(t)ide reverse-transcriptase inhibitors (NRTIs) and another compound, which can be an integrase strand transfer inhibitor , or the ritonavir-boosted protease inhibitor darunavir ,3. TheseThe co-formulated regimens of elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil fumarate (E/C/F/TDF) and abacavir/lamivudine + dolutegravir (ABC/3TC + DTG) have been extensively studied in initial ART therapy. On a total of 1,067 participants receiving ABC/3TC + DTG, 88.3% 942) had an HIV-1 RNA < 50 copies/mL at 48 weeks 42 had an,11. But SINGLE included 833 patients in 2010 ,12;GS-US-236-0102 included 700 patients in 2011 ,13.Despite showing similar rates of efficacy among the integrase inhibitors, the different rates of efficacy of EFV/FTC/TDF in both studies (higher rates of discontinuation due to adverse events [10 vs 5%] in the SINGLE vs GS-US-236-0102) established superiority of ABC/3TC + DTG and non-inferiority of E/C/F/TDF against EFV/FTC/TDF. Both studies have now reported data at 48, 96 and 144 weeks.Haute Autorité de Santé (HAS) in 2009 [The randomized controlled trial is the gold standard for evaluating the relative efficacy of healthcare technology. However, many competing interventions have not been directly compared in randomized clinical trial and indirect treatment comparisons have been advocated when direct evidence is not available . An indi in 2009 .The objective of this analysis was to perform an indirect treatment comparison of the efficacy, safety, rates of virological failure and emergence of resistance at 48, 96 and 144 weeks of E/C/F/TDF to ABC/3TC + DTG by using these two randomized trials which compared each of these regimens to EFV/FTC/TDF.The studies compared here were conducted at one year interval (2010 and 2011), and recruited participants with similar baseline characteristics.None of the authors had access to identifying patient information. Therefore, there was no need for an ethic statementFor ABC/3TC + DTG (study SINGLE) the aggregated data were extracted from:The publications of Walmsley et all  for the The communication and the publication of Walmsley et al ,17 for rThe publication of Walmsley et al and the communication of Pappa et al. , 19 for For E/C/F/TDF (study GS-US-236-0102) the aggregated data were extracted from:The publications of Sax et all  for the The publications of Zolopa et all  for the The communication and the publication of Wohl et al. ,21 and tThese studies had similar designs and compared E/C/F/TDF or ABC/3TC + DTG versus EFV/FTC/TDF . Both weIn the SINGLE study, randomization was stratified according to the plasma HIV-1 RNA level at the time of screening  and the CD4+ T-cell count (≤200 per cubic millimeter vs. >200 per cubic millimeter). In the study GS-US-236-0102, randomization was only stratified by HIV RNA concentration at screening . In both studies eligible patients were randomised in a 1:1 ratio.The GS-US-236-0102 remained double blinded until week 144 but the SINGLE study was unblinded at week 96 and continued through week 144.Participants in both studies were adults infected with HIV-1, aged at least 18 years with plasma HIV-1 RNA concentrations of 5,000 copies/mL or more (GS-US-236-0102) or 1,000 copies/mL or more (SINGLE) and no previous use of antiretroviral drugs. There was no screening CD4 cell count limit in the inclusion criteria. Participants had to have an estimated glomerular filtration rate of at least 70 mL/min (GS-US-236-0102) or 50 mL/min (SINGLE) and be susceptible to all study drugs by HIV-1 genotype at screening. Participants in the SINGLE study were negative for the HLA-B*5701 allele. Randomization was stratified according to the plasma HIV-1 RNA level at the time of screening  in both studies, and also to the CD4+ T-cell count (≤200 per cubic millimeter vs. >200 per cubic millimeter) in the SINGLE study.In the snapshot analysis, participants with HIV-1 RNA less than 50 copies/mL between days 309 and 378 (week 48 window) were classified as virological success in the GS-US-236-0102 study, and between week 42 through week 54 in SINGLE.Participants with missing HIV-1 RNA data for weeks 48, 96 and 144 analysis window, who discontinued study drug, or who changed therapy being suppressed at the previous time points were considered as having no data in the window.Virological failure was defined as HIV RNA > 50 copies/mL after week 8 in the GS-US-236-0102 study and after week 24 in SINGLE. For those patients failing, genotype testing was conducted in the confirmatory sample (second sample) if HIV-1 RNA > 400 copies/mL in GS-US-236-0102. In the SINGLE study, genotyping test was conducted in the first sample showing HIV RNA > 50 copies/mL. We decided to analyze the resistance emerging at virological failure in both studies at 144 weeks to allow the maximal number of failures and resistance tests done [Finally, 707 patients were enrolled in the GS-US-236-0102 study and 700 (99%) contributed to the ITT population, and 844 patients were enrolled in the SINGLE study, with 833 (99%) receiving study drug and contributing to the ITT population.An indirect method proposed by Bucher et al. in 1997 has been broadly utilized for indirect treatment comparisons in meta-analyses of RCTs for discrete data .This model was developed with the odds ratio (OR) as the measure of treatment effect. However, OR are used for ratio calculations and we could not use this method for the calculations of differences. Therefore, a generalization of the Bucher approach that allows indirect comparisons using other measures of association, including risk differences, has been recommended .Comparisons between treatments were made using a risk difference measure:1) has been calculated between E/C/F/TDF and EFV/FTC/TDF: RD = PE/C/F/TDF − PEFV/FTC/TDF, where PE/C/F/TDF is the probability of virologic success, development of viral resistance or safety parameters for E/C/F/TDF and PEFV/FTC/TDF for EFV/FTC/TDF;A risk difference (RD2) has been calculated between ABC/3TC + DTG and EFV/FTC/TDF: RD2 = PABC/3TC + DTG − PEFV/FTC/TDF, where PABC/3TC + DTG is the probability of virologic success, development of viral resistance or safety parameters for ABC/3TC + DTG and PEFV/FTC/TDF for EFV/FTC/TDF;A risk difference (RD1 and RD2 are combined by subtracting the first by the second: RD = RD1 − RD2 (it is a difference of difference). The result represents the indirect difference between E/C/F/TDF and ABC/3TC + DTG.The 2 preceding result RDWhen the risk difference percentage is greater than 0, this means that the proportion is higher for E/C/F/TDF as compared to ABC/3TC + DTG:For efficacy, a positive result means that a higher proportion of patients on E/C/F/TDF reached the endpoint of HIV-1 RNA < 50 copies/mL when compared to ABC/3TC + DTG;For resistance, a positive result means that a higher proportion of patients on E/C/F/TDF developed resistance when compared to ABC/3TC + DTG;For safety, a positive result means that a higher proportion of patients on E/C/F/TDF experienced adverse events when compared to ABC/3TC + DTG,If the risk difference percentage is lower than 0, this means that the proportion is higher for ABC/3TC + DTG in comparison to E/C/F/TDF.Most of the baseline characteristics of the study populations in the integrase arms of both clinical trials were similar . There wOverall results for efficacy are shown in Results of the indirect comparison showed no statistically significant difference between E/C/F/TDF and ABC/3TC + DTG in the adjusted risk difference (relatively to the control group) of the efficacy endpoint of achieving HIV RNA < 50 copies/mL at 48 weeks: -3.7%  . The adjThe analysis did not show statistically significant differences between E/C/F/TDF and ABC/3TC + DTG in the risk difference for serious adverse events: +5.7%  . The adjRates of virological failure were comparable in both studies. In GS-US-236-0102, 7% of patients on E/C/F/TDF and 10% of subjects on EFV/FTC/TDF were considered virological failures at week 144, while in SINGLE, rates were 10% and 7% for ABC/3TC + DTG and EFV/FTC/TDF, respectively.As pointed out previously, resistance was analysed differently in GS-US-236-0102 and SINGLE. While 2.9% (10/348) patients on E/C/F/TDF in GS-US-236-0102 and no patients on ABC/3TC + DTG in SINGLE developed resistance up to week 144, the proportion of patients on EFV/FTC/TDF developing resistance at week 144 were 3.9% and 1.4% in GS-US-236-0102 and SINGLE, respectively.Results of the indirect comparison showed no statistically significant risk difference of the viral resistance of 1.2%  at week 48, 1.7% at week 96  and 2.2%  at week 144 .Indirect comparison analysis are recommended by the French, Canadian and UK guidelines in case of no direct clinical studies, but are not very commonly applied in regulatory submissions ,27. HoweOur indirect comparison was aimed to compare the efficacy, emergence of resistance and safety of E/C/F/TDF to ABC/3TC + DTG. The results of two randomized trials using the same comparator (EFV/FTC/TDF) were analysed. The results show equivalence between E/C/F/TDF and ABC/3TC + DTG in terms of efficacy, resistance and most safety results.These results are in accordance with previous works. In a network meta-analysis, Patel et al compared several nucleoside reverse transcriptase inhibitor regimens . The autAlthough the 2 studies we analyzed were very similar in their methodologies, the GS-US-236-0102 remained blinded until week 144 but the SINGLE study was unblinded at week 96. This difference may have biased some of the analysis we have performed. In GS-US-236-0102 the proportion of patients reported as having ‘No data’ for E/C/F/TDF and EFV/FTC/TDF were 5% and 9% at week 48, 9% and 11% at week 96, and 12% and 15% at week 144. In the SINGLE trials these percentages were 7% and 13% at week 48, 12% and 20% at week 96, and 18% and 30% at week 144 respectively for ABC/3TC + DTG and EFV/FTC/TDF.The randomizations were quite similar and we believe that the differences did not bias the indirect comparison analysis. In the study GS-US-236-0102, participants had to have an estimated glomerular filtration rate of at least 70 mL/min and in the SINGLE study, persons with an estimated creatinine clearance of less than 50 ml per minute were excluded from the study. Hereto, we believe that these differences did not generate a significant bias the indirect comparison analysis.Most of the baseline characteristics of the study populations in the integrase arms of both clinical trials were similar. However, there were significant differences in race, with a lower proportion of white patients in the GS-US-236-0102 trial compared to the SINGLE study. The relation between race and efficacy of AIDS drugs has been questioned. However, the causes of this relation seem rather due to cultural and social factors which are correlated with race, rather than race itself . TherefoThere was a high dropout rate in the EFV/FTC/TDF arm of the SINGLE trial between week 96 and 144 (10% (30%-20%)) as compared to the study GS-US-236-0102 (4% (15%-11%)). This higher dropout rate may be due to the open label of the SINGLE trial at week 96 . This may have increased the difference in virologic success between ABC/3TC+DTG and EFV/FTC/TDF (as compared to E/C/F/TDF). Hence, as our calculations were based on the risk differences between both studies, this may have induced a higher difference in virologic success, although not statistically significant.This difference between the two clinical trials may also explain some results observed for the indirect safety analysis. The higher proportion of patients experiencing a discontinuation of E/C/F/TDF (compared to ABC/3TC+DTG) at week 144 may also be explained by the high difference of dropout rate between week 96 and 144 for EFV/FTC/TDF in the SINGLE study.In regards to discontinuations, the higher rate of dropouts for E/C/F/TDF in GS-US-236-0102 could initially be related to elevation in serum creatinine due to inhibition of the renal transporter MATE-1. This phenomenon was clearly understood later in time and was also found in the DTG studies, and investigators felt more comfortable continuing patients with these changes as they gained experience with the medications.Many competing interventions have not been directly compared in randomized clinical trial and indirect methods have been commonly used in meta-analyses.Several reasons can explain the lack of direct comparisons. Cost and time of conducting clinical studies accompanied with the fact that standard of care can change quickly are reasons to look for alternate solutions such as indirect comparisons to get an assessment of the true level of effect of the new drug . MoreoveAs for clinical trials, one should make his own point of view from what is statistically significant for the clinical interest of the results. Besides that, the absence of a statistical significant result does not imply an absence of the difference and absence of evidence is not evidence of absence. The U.S. Department of Health and Human Services has provided guidelines for non-inferiority and superiority clinical trials for HIV treatments . These rThere are limitations in the method that we used.We only worked on statistical aggregated results of data because we did not have access to the individual data of both trials. We did not perform a systematic review. We identified these 2 studies as very similar and we believe that it would be interesting to perform this indirect comparative analysis. There are other clinical studies on integrase inhibitors , but this drug is not available as a STR or QD posology and the included populations are quite different across studies, which complicate the analysis. Finally we preferred to compare these 2 similar studies rather than including more studies which would have needed questionable adjustments.The results we obtained depend on the quality and comparability of the populations included in the trials used to make the analysis. The studies we used are similar in terms of patients’ characteristics and the methodologies used to conduct the two studies were consistent. Only data corresponding to both, the definition for the treatment of missing data and of the virologic suppression were included in the analysis to ensure comparability of results. However, as stated above, the fact that study GS-US-236-0102 remained blinded until week 144 but the SINGLE study was unblinded at week 96 may have biased some indirect comparisons analysis.With the limitation that we did not perform a systematic review we can conclude that:The indirect efficacy comparisons show equivalence between E/C/F/TDF and ABC/3TC + DTG. For efficacy, the difference between both regimens at week 48, 96 and 144 were small and not statistically significant;Resistance and all safety results (except for discontinuation due adverse events) also show equivalence between the 2 regimens.Indirect comparative data between active drugs, such as these results, assist clinicians in utilizing these agents in real life practice.S1 Appendix(XLS)Click here for additional data file.


Visceral leishmaniasis (VL) has become an important opportunistic infection in persons with HIV-infection in VL-endemic areas. The co-infection leads to profound immunosuppression and high rate of annual VL recurrence. This study assessed the effectiveness, safety and feasibility of monthly pentamidine infusions to prevent recurrence of VL in HIV co-infected patients.A single-arm, open-label trial was conducted at two leishmaniasis treatment centers in northwest Ethiopia. HIV-infected patients with a VL episode were included after parasitological cure. Monthly infusions of 4mg/kg pentamidine-isethionate diluted in normal-saline were started for 12months. All received antiretroviral therapy (ART). Time-to-relapse or death was the primary end point.Seventy-four patients were included. The probability of relapse-free survival at 6months and at 12 months was 79% and 71% respectively. Renal failure, a possible drug-related serious adverse event, occurred in two patients with severe pneumonia. Forty-one patients completed the regimen taking at least 11 of the 12 doses. Main reasons to discontinue were: 15 relapsed, five died and seven became lost to follow-up. More patients failed among those with a CD4+cell count ≤ 50cells/μl, 5/7 (71.4%) than those with counts above 200 cells/μl, 2/12 (16.7%), (p = 0.005).Pentamidine secondary prophylaxis led to a 29% failure rate within one year, much lower than reported in historical controls (50%-100%). Patients with low CD4+cell counts are at increased risk of relapse despite effective initial VL treatment, ART and secondary prophylaxis. VL should be detected and treated early enough in patients with HIV infection before profound immune deficiency installs. Relapse of visceral leishmaniasis (VL) among HIV co-infected patients occurs universally. Evidence on the use of secondary prophylaxis especially in anthroponotic transmission regions was lacking. It was found out now that secondary prophylaxis in addition to antiretroviral therapy for VL in people with HIV infection is useful to decrease the relapse rate. However, this intervention is more effective when started before profound immune deficiency. Patients with low CD4 cell counts continued to relapse significantly despite the use of secondary prophylaxis as compared to those with high CD4 cell counts. Earlier VL case detection and management is crucial. This is the first adequately powered trial that has addressed the use of secondary prophylaxis for prevention of VL relapse in HIV co-infected patients. Leishmania donovani complex. While the Indian-subcontinent, East-Africa and Brazil share the major disease burden, it was long known as a rare pediatric disease in the Mediterranean basin. However, in the HIV-era, VL resurged in Southern Europe in adults with HIV co-infection [Visceral leishmaniasis (VL) is a fatal-but treatable- disease caused by a protozoan belonging to the nfection  and has nfection ,3. Todaynfection  and VL infection ,6.The profound immune deficiency in HIV/VL co-infection leads to poor treatment outcome and frequent recurrence of VL. A few case series studies showed 50% to 100% relapse in a year period without antileishmanial secondary prophylaxis –11 compaL infantum and transmission is zoonotic [Secondary prophylaxis for the prevention of VL relapse is recommended in international guidelines ,14 basedzoonotic ,11,15,16L donovani and transmission is anthroponotic, the HIV co-infection rate reaches 20 to 30% with up to 56% relapse in a year in patients on ART but without secondary prophylaxis [In northwest Ethiopia, where VL is caused by phylaxis . Patientphylaxis . Using fphylaxis . Thus, wphylaxis ,18,19. TClinicaltrials.gov (code NCT01360762).The protocol of the study was approved by the Ethiopian Regulatory Authority , the National Research Ethics Review Committee (NRERC) and the Institutional Review Board of University of Gondar in Ethiopia. Additionally, it was also approved by the Ethics Review Board of Médecins Sans Frontières, and the Ethics Committee of Antwerp University Hospital, Belgium. All subjects were included in to the study after written informed consent was signed. Free treatment was provided. Patients were compensated for transport and food during their visits to the study sites. All study documents were kept confidential and were accessible for the study team, monitors and inspectors. Trained clinical trial monitors carried out two pre-study visits, one initiation visit and 6 monitoring visits according to the WHO and ICH Good Clinical Practices standards. Regulatory inspection was carried out by FMHACA at both sites during the study period. The independent Data and Safety Monitoring Board met five times during the study and assessed the progress of the study when every quarter of total sample recruitment was achieved. The protocol was registered in This was an open label, single arm trial designed to investigate the effectiveness, safety and feasibility of monthly pentamidine prophylaxis to prevent VL relapse in patients with HIV. The study has three phases, an initial 12 months of monthly pentamidine (main study period), six months extended treatment period (with monthly pentamidine) for those who remain with CD4 count less than 200cells/μl at the end of 12months follow-up, and a subsequent 12months follow-up after the prophylaxis to assess long term outcomes. The findings of the latter two phases will be published in the future.The study was conducted in Northwest Ethiopia–at the Leishmaniasis Research and Treatment Center (LRTC) at University of Gondar Hospital (UoGH) and at the Abdurafi Health Centre. They are the largest leishmaniasis treatment centers in the region and are supported by the non-governmental organizations Drugs for Neglected Diseases initiative (DNDi) and Médecins sans Frontières respectively.Recruitment of the patients for the study proceeded in two steps. During pre-screening, age 18 or more years, parasitological diagnosis of VL, documented HIV test result and acceptable distance of residence from the trial centres for monthly follow-up were checked. Eligible patients were then approached for consent.Current primary cases were those presenting with VL disease for the first time and current relapse cases were patients presenting with two or more episode of VL. Those with active VL disease were admitted to the treatment centres for VL treatment and combination ART (initiated or continued). The drugs used to treat VL were sodium stibogluconate alone or in combination with paromomycin and Liposomal amphotericin B alone or in combination with miltefosine. Treatment of VL was prolonged or changed from one regimen to another when there was no cure with the initial regimen used. The current primary VL cases were included in the study after VL cure if they had a CD4+cell count less than 200 cells/μl or a WHO stage 4 HIV/AIDS defining condition (other than VL) while the current relapse cases were included in the study regardless of the CD4+cell and WHO stage of the co-morbidities. Patients who were treated for VL before the start of the study recruitment but in follow-up (taking ART) were defined as past VL cases and were included if their CD4+cell count at the time of screening for the study was less than 200 cells/μl or if they had a WHO stage IV-defining illness on presentation. All cases were included after ascertaining parasitological cure (no parasite on tissue aspirate microscopy).There were three types of study participants considered at increased risk of relapse. Patients presenting with active VL disease during the recruitment period were classified into two groups. Renal dysfunction , diabetes, pregnancy and lactation, and chronic medical conditions (e.g. cardiac illnesses) were exclusion criteria.Pentamidine isethionate (provided by Sanofi-Aventis) was started one month after VL cure for the current VL patients; and soon after the inclusion criteria were met for past VL cases. The monthly infusion was continued until the primary end points are met. Pentamidine isethionate 300mg powder was reconstituted with 5ml distilled water and the 4mg/kg (maximum 300mg) was drawn and further diluted in 200ml normal saline for infusion over one hour. Frequent blood pressure monitoring was done during infusion. Any adverse events observed were documented.At every visit weight, height, temperature, blood pressure, pulse, spleen and liver size and nutritional status were checked. Monthly full blood count, creatinine, liver function tests and blood glucose; every fourth month electrocardiography tracing and amylase level; and every sixth month CD4+cell count were monitored. HIV viral load determination was done only when clinically indicated and logistically possible. All adverse events were documented, and all the serious adverse events were reported to the sponsor and concerned Ethics Committee via a fast track procedure. Adherence to ART and co-trimesaxole was monitored by patient interview and pill count. The nationally recommended definition for ART adherence as “Good” missing less than three doses; “Fair” missing less than nine doses and “Poor” missing more than nine doses per month was used. Patients found with additional opportunistic infections and/or ART failure were managed according to the national Ethiopian guidelines . During HIV was diagnosed followed the national diagnostic algorithm of using two sequential positive rapid test results; KHB  followed by STAT-PAK . In case of discrepancy between the two tests, the Uni-Gold  was used as a tie breaker in Gondar. In Abdurafi, the confirmation was done by ImmunoComb  after two positive rapid tests.Leishmania amastigotes. Tissue aspiration was repeated at the end of treatment to assess parasitological cure defined as no parasite on microscopy from the tissue aspirate. Splenic aspiration was avoided whenever the patients had bleeding tendency or the platelet count was less than 50,000/μl.VL was diagnosed by tissue aspirates (spleen or bone marrow) and microscopy of the giemsa stains for + T lymphocyte count was done at recruitment and every sixth months during follow-up using FACS counter . The haematological analysis was done by a haematology analyser–Beckman Coulter AcT diff, Beckman Coulter Inc., 2003, USA.CD4We report here the outcomes as assessed by the end of 12 months. The primary effectiveness outcome was time to relapse or death ; while the primary safety outcome was the proportion of patients with pentamidine related serious adverse events (SAEs) or pentamidine related adverse events that led to the discontinuation of the drug. An adverse event was considered drug-related when the relationship was judged as possibly, probably or definitely related according to the treating physician. The primary outcome for feasibility was the proportion of patients that completed at least 90% of the scheduled visits .Secondary variables of interest related to safety were ‘any drug related adverse event and ‘any SAE’; while feasibility-related variables included ‘the number of treatment discontinuations, interruptions, and additional clinical/therapeutic interventions needed’. Causes of death were analyzed as tertiary end points.Sample size was calculated with a required precision of 10% for primary effectiveness, 7.5% for main safety analysis and 12.5% for tolerability. The anticipated main analysis outcomes were a failure rate of 20% and a frequency of drug related SAEs of 10%. With these assumptions, the required sample size was 65. Allowing for 10% of patients lost to follow-up, the final sample size was calculated to be 72.A CONSORT diagram  and checEffectiveness: Effectiveness was analyzed using Kaplan-Meier survival analysis with time to relapse or death as outcome measure. "Failed" means the patient died or parasites were detected in tissues aspirates. Aspirates were taken in case of clinical suspicion of relapse. All other patients were considered free of relapse and were censored at 12 months (for patients who completed follow-up), or at their last visit for patients lost to follow-up. In principle, death was defined as all-cause mortality. The results were given as probability of relapse free survival with 95% confidence interval at 6 and 12 months. Patients who were lost to follow-up or discontinued the treatment for reasons not related to VL relapse before the end of the follow-up period were censored in the main study analysis, but were included as treatment failures in a “worst-case” scenario.Safety: Adverse events were coded using the Medical Dictionary for Regulatory Activities (MEDDRA) and were analyzed based on counts of patients with a specific category and not on counts of individual AEs. Primary safety outcome was described in terms of counts of patients with drug-related SAEs or adverse events that led to study drug discontinuation. Counts (%) of patients with any SAE and any drug-related adverse events were presented as secondary safety outcomes.Feasibility: The primary outcome for feasibility was the proportion of patients that completed at least 11 of the 12 monthly doses of the prophylaxis according to the protocol without experiencing relapse or drug-related SAEs expressed in percentage. The secondary feasibility endpoint was computed as the number (%) of patients who interrupted (temporarily or permanently), and the number of clinical interventions and/or therapeutic procedures needed.From a total of 176 HIV/VL patients, 74 were recruited into the study (38 at Abdurafi and 36 at Gondar)  in the p2) and with a history of VL relapse, 43 (58%). The median duration on ART was 7 months. Tenofovir, lamivudine and efavirenz combination was the common (74%) ART regimen used. While the median CD4+cell count at ART initiation was 70cells/μl, it was 127 cells/μl at inclusion into the study, with 60 (85.7%) having a CD4+cell count below 200cells/μl   and 71% (95% CI: 59–80) respectively , and it Two patients hospitalized for severe pneumonia had renal failure that was possibly related to pentamidine. One patient had to stop the study drug due to hyperglycemia though it normalized within a month.There were a total of 21 SAEs (excluding admissions due to VL relapse) that occurred in 17 (23%) patients ; and 42 Forty-one (55%) of the participants completed the follow-up taking at least 11 of the planned 12 doses without experiencing relapse, death or drug-related SAEs. Four patients who missed more than one dose still had a successful outcome. The remaining 29 patients discontinued pentamidine permanently; 15 (20.3%) of them because of relapse, 7 (9.5%) were lost to follow-up, 5 (6.8%) died, one patient had to stop due to hyperglycemia and another patient refused to take the study drug.Clinical and therapeutic interventions for pentamidine related adverse events were needed for 11 (14.9%) of the study participants. The common therapeutic interventions were additional intravenous fluid during pentamidine administration and reducing the rate of pentamidine infusion each happening ten times. Oral hydrations, prolonged hospital observation and additional medication during pentamidine infusion were each required twice and once glucose supplementation was done.There were five deaths, three in hospital and two out of the hospital, mainly due to infections. Two patients with severe pneumonia and renal failure died in hospital. The other hospital death was due to meningitis. One patient died of cryptosporidial diarrhea. The cause of death of the fifth patient was considered to be severe pneumonia based on verbal description from his relatives.+cell count ≤ 50cells/μl, whereas 2/12 (16.7%) failed in those with a CD4+cell count greater than 200cells/μl (p = 0.005) (There were 5/7 (71.4%) failures among patients with a CD4= 0.005) . Age, bo= 0.005)  and diagHIV viral load was done only for eight of the patients who failed (1 death and 7 relapse cases) and it was undetectable in five of them.L infantum region, the relapse rate was reduced from 67% to 31% with chemoprophylaxis [The probability of failure (relapse or death) from secondary VL chemoprophylaxis within 1 year was 29% which is lower than the 50% to 100% reported in case series without prophylaxis in Europe –11. The phylaxis . Our stu+ cell counts, but not with previous multiple relapses as seen before in a study in Ethiopia [Our data corroborate the risk of relapse associated with low CD4Ethiopia . HoweverEthiopia . Early rEthiopia . SimilarEthiopia ,16,23–25Seven (9.5%) of the study participants were lost to follow-up and four (5%) of the patients interrupted more than one dose before the primary end point was met. Despite the fact that our study patients belonged to a highly mobile and difficult to trace population group (migrant workers), the proportion of lost to follow-up did not exceed the 10% accounted in the initial sample size calculation.Our study has several limitations. It is not a randomized controlled trial because there was no other antileishmanial drug available or recommended by the Ethiopian national guidelines to compare with. Secondly, because international guidelines recommend secondary prophylaxis to prevent VL recurrence in HIV equipoise was hard to claim ,14. We dIn conclusion, longer VL relapse free survival was achieved using pentamidine as secondary prophylaxis in people with HIV infection. However, patients with profound immune deficiency were still at risk of relapse. Thus, there is a need to investigate additional treatment options for this group of patients. Early VL case detection (before profound immune deficiency) is crucial for effective management and prevention of relapses .S1 Checklist(DOC)Click here for additional data file.S1 Table(DOCX)Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.


Switching therapy studies are usually designed as second-line antiretroviral treatment (ART) in patients without previous virologic failures. Combined ART (cART) with DRV/r and ETR has a good pharmacokinetic profile, high genetic barrier and has been proved as rescue therapy. The aim of our study was to analyze efficacy and safety of therapy with DRV/r plus ETR in treatment experienced HIV-patients with previous therapeutic failures that need to switch ART. We present results at first 24 weeks.Multicentre retrospective observational study. Inclusion criteria: adult HIV-patients on ART with HIV-VL <1000 cop/mL who started their ART with DRV/r (600/100 bid or 800/100 qd)+ETR by adverse events, non-adherence, tolerability or prevention of future complications. Patients with acute AIDS events, HBV, pregnancy, drug addiction or previous selected mutations to DRV or ETR were excluded.Ninety-nine patients were included, mean age: 47 years (r: 22–79); 70% men, 40.4% previous AIDS event and 39.3% HCV. Ninety-one patients had received ≥3 cART regimens and 45≥5, 75 patients had HIV-VL <50 cop/mL and 24 low-level viremia (LLV): 297.5±261.4 cop/mL, CD4+ 568±279 cells/µL. ART before switching: NRTI+PI/r (33%), NNRTI (17%), PI/r+NNRTI (23%), PI/r+INI (13%), other (14%). Main reason to switching was: toxicity/intolerance 50 patients ; improving adherence 26 patients; prevention of complications 19 patients. Nine subjects withdrew ART during follow-up because: intolerance or new toxicity three; non-adherence two; simplification to DRV/r monotherapy two; persistence of previous toxicity one; virologic failure one. At week 24, among patients who continued with DRV/r+ETR (n=90): 81 (89%) had VL<50 cop/mL, in those with with HIV-VL<50 at baseline (67/90), 94% persisted with <50 cop., and in those with LLV (24/90), 61% (n=14) achieved a VL<50 cop. We didn't observe any significant difference in lab parameters between baseline and week 24. Estimated glomerular filtrate rate increased from 83.4±24.7 to 88.5±56.8 mL/min, p=NS. Regarding reason to switching, it improved in 42 cases, no changes: 20 cases; worsened: 4 cases, and non-applicable or unknown: 24 cases.Switching to dual therapy with DRV/r+ETR is an effective strategy in selected heavily experienced ART patients, even in those with LLV (<1000 cop/mL). This cART is safe and well tolerated, can reduce number of pills and improve adherence.


Adherence to antiretroviral (ARV) treatment for HIV-1 is crucial to achieving optimal clinical outcomes. Simplification of regimens with once-daily single-tablet regimens (STRs) can improve adherence compared to multi-tablet regimens (MTRs). This study compared real-world persistence (a proxy for treatment effectiveness and adherence) between HIV-1 infected patients receiving STRs versus MTRs.Adult HIV-1 infected patients starting their first observed ARV regimen (with at least six prior months of no ARV treatment) were identified in the MarketScan claims database (10/2008–03/2014). Persistence was measured as the time from the index regimen start date to the end of the first 90-day gap between fills for any ARV in the index regimen, or to the start date of an ARV not in the index regimen. Persistence was described using Kaplan–Meier curves and compared using log-rank tests, and Cox proportional hazards models adjusted for age, gender, insurance type, region, employment status, Charlson Comorbidity Index, other comorbidities, hospitalizations, emergency room visits and office visits. STRs were further stratified by regimen.P<0.001; A total of 3257 patients (37%) initiated MTRs, and 5484 (63%) initiated STRs, including 4409 on efavirenz (EFV)/tenofovir (TDF)/emtricitabine (FTC), 484 on rilpivirine (RPV)/TDF/FTC, and 591 on elvitegravir (EVG)/cobicistat (COBI)/TDF/FTC. Median persistence was 45.0 months for STRs versus 15.2 months for MTRs P<0.001; . Median Among HIV-1 infected patients, the use of STRs was associated with longer regimen persistence compared with MTRs. Among STRs, EVG/COBI/TDF/FTC and RPV/TDF/FTC were associated with significantly longer persistence than EFV/TDF/FTC.