the term “ liquid formulation ” refers here particularly to a solution , a suspension with solid particles dispersed in a liquid , an emulsion with liquid droplets dispersed in a liquid , or to a syrup . according to one preferred embodiment , the liquid drug formulation is a solution of compound i in a suitable carrier , which can be a single carrier or a mixture of several carriers . the compounds of formula i have very low solubility in water . the carrier shall therefore preferably comprise one or more lipophilic ingredients . in order to achieve enhanced bioavailability it is preferable to use digestible lipids such as triglycerides , diglycerides , fatty acids , phospholipids , or the like instead of indigestible oils such as mineral oils ( porter and charman , 2001 ). a special group of useful carriers or ingredients therein may be cholane derivatives . u . s . pat . no . 4 , 117 , 121 disclosed a group of cholane derivatives useful to decrease cholesterol level and to increase bile flow . the bioavailability enhancing ingredients are , however , not restricted to the aforementioned . according to another preferred embodiment , the liquid drug formulation is a suspension of fine solid particles of the compound i in a liquid . the liquid can be a lipophilic or hydrophilic liquid or a mixture of several liquids . said liquids can also comprise dissolved ingredients . by decreasing the particle size of the dispersed drug compound , the surface area available for digestion and drug release is enhanced . preferably at least 90 % of the drug substance shall have a particle size less than 150 micrometer , and 50 % of the drug substance shall have a particle size less than 25 micrometer . especially preferably , 90 % of the drug substance shall have a particle size less than 50 micrometer , and 50 % of the drug substance shall have a particle size less than 15 micrometer . according to a third preferred embodiment , the liquid formulation is an emulsion . because the aqueous solubility of compound i is very low , the emulsion is preferably a dispersion of a lipophilic phase ( e . g ., a solution of compound i in a lipophilic liquid ) in an aqueous phase ( oil - in - water emulsion ). the emulsion may comprise additional components such as stabilizers ( surfactants ), emulsifiers and thickeners . according to a particularly preferred embodiment , the emulsion is a microemulsion or nanoemulsion . micro - and nanoemulsions are , in contrast to conventional emulsions , isotropic , transparent and thermodynamically stable . the average size of the dispersed droplets is in a microemulsion typically about 10000 nm or below and in a nanoemulsion 100 nm or below . according to a fourth preferred embodiment , the liquid formulation is a syrup . typical examples of semisolid oral formulations are gels and pastes . gels are created by adding a gelatinizer such as gelatine or a polysaccharide to a solution , suspension or emulsion comprising compound i . according to one preferred embodiment , the gel is created by addition of a gelatinizer to a microemulsion according to ep 760651 b1 . although the liquid formulations such as solutions , emulsions and suspensions can be packed in larger bottles for many doses , it may be preferable to have the drug formulation packed into a unit dosage form , such as a capsule . such capsule formulations are called softgel capsules . soft gelatin capsules ( or softgel capsules ) consist of a liquid or semisolid matrix inside a one - piece outer shell , such as a gelatin shell . the drug compound itself may be either in solution , suspension or emulsion in the capsule - fill matrix . the characteristics of the fill matrix may be hydrophilic ( for example polyethylene glycols ) or lipophilic ( such as triglyceride vegetable oils ), or a mixture of both hydrophilic and lipophilic ingredients . significant advances have been made in recent years in the formulation of fill matrices . as examples can be mentioned microemulsions or nanoemulsions of the drug encapsulated as preconcentrates in the capsule . this means that the fill matrix is a concentrated micro - or nanoemulsion , i . e ., a combination of a lipophilic liquid containing the hydrophobic drug , a small amount of hydrophilic liquid and a surfactant . after oral administration the microemulsion will become diluted in the gastrointestinal fluid . alternatively , the matrix may comprise only the ingredients , i . e ., the drug , a lipid or a lipid mixture and one or more surfactants . the ingredients will , upon administration , spontaneously create a microemulsion ( or nanoemulsion ) in the gastrointestinal fluid . the softgel capsule consists for example of gelatin , water and a plasticizer . it may be transparent or opaque , and can be coloured and flavoured if desired . preservatives are not required owing to the low water activity in the finished product . the softgel can be coated with enteric - resistant or delayed - release material . although virtually any shape softgel can be made , oval or oblong shapes are usually selected for oral administration . the improved drug formulation according to this invention is particularly useful when treating women during or after the menopause . however , the method according to this invention is not restricted to women in this age group . the term “ metabolite ” shall be understood to cover any ospemifene or ( deaminohydroxy ) toremifene metabolite already discovered or to be discovered . as examples of such metabolites can be mentioned the oxidation metabolites mentioned in kangas ( 1990 ) on page 9 ( tore vi , tore vii , tore xviii , tore viii , tore xiii ), especially tore vi and tore xviii , and other metabolites of the compound . the most important metabolite of ospemifene is 4 - hydroxyospemifene , which has the formula the use of mixtures of isomers of compound ( i ) shall also be included in this invention . the improved drug formulation according to this invention is useful in any application of ospemifene , especially when the compound is used for treatment or prevention of osteoporosis or for treatment or prevention of symptoms related to skin atrophy , or to epithelial or mucosal atrophy . a particular form of atrophy which can be inhibited by administering of ospemifene is urogenital atrophy . symptoms related to urogenital atrophy can be divided in two subgroups : urinary symptoms and vaginal symptoms . as examples of urinary symptoms can be mentioned micturation disorders , dysuria , hematuria , urinary frequency , sensation of urgency , urinary tract infections , urinary tract inflammation , nocturia , urinary incontinence , urge incontinence and involuntary urinary leakage . as examples of vaginal symptoms can be mentioned irritation , itching , burning , malodorous discharge , infection , leukorrhea , vulvar pruritus , feeling of pressure and postcoital bleeding . according to previous data , the optimal clinical dose of ospemifene is expected to be higher than 25 mg daily and lower than 100 mg daily . a particularly preferable daily dose has been suggested in the range 30 to 90 mg . at the higher doses ( 100 and 200 mg daily ), ospemifene shows properties more similar to those of tamoxifen and toremifene . due to the enhanced bioavailability according to the method of this invention , it can be predicted that the same therapeutical effect can be achieved with doses lower than those recommended earlier . the invention will be disclosed more in detail in the following non - restrictive example . a clinical study was carried out in order to evaluate the bioavailability of ospemifene given as tablet , hard gelatine capsule and as solution . healthy male caucasian individuals ( n = 23 ), age 18 to 35 years , were subjected to 3 different tests in which they were given a ) two hard gelatine capsules , each containing 30 mg ospemifene ; b ) one tablet containing 60 mg ospemifene ; or c ) 3 . 7 g of a solution containing 60 mg ospemifene . in c ) the solvent was a mixture of ethanol - peg - propyleneglycol ( 2 , 7 : 1 : 2 , 5 ). the tests were separated from each other by a washout period lasting at least one week . blood samples for the determination of serum ospemifene concentrations were collected during each test at several time points after administration . serum ospemifene concentrations were determined using reversed phase hplc with fluorescence detection after photochemical activation . the results are shown in fig1 , which discloses the mean serum concentration of ospemifene versus time after administration after a single oral dose of 60 mg ospemifene given as two 30 mg hard gelatine capsules ( triangles ), as one 60 mg tablet ( circles ) or as a dose of a solution containing 60 mg ospemifene ( stars ). it can be seen that peak concentrations were much higher after administration of solution ( 700 ng / ml ) than after tablet and hard capsules , which were very similar , 280 and 277 ng / ml , respectively . accordingly , the auc - values were substantially higher after solution ( approximately 3000 ng h / ml ) when compared to the auc - values of tablets and hard capsules ( approximately 2000 ng h / ml ). therefore it can be concluded that the absorption of ospemifene from solution was much faster and the bioavailability much higher than from tablets and hard capsules . additionally , the variability of the pharmacokinetic parameters decreased . it will be appreciated that the methods of the present invention can be incorporated in the form of a variety of embodiments , only a few of which are disclosed herein . it will be apparent for the expert skilled in the field that other embodiments exist and do not depart from the spirit of the invention . thus , the described embodiments are illustrative and should not be construed as restrictive .
this invention relates to a liquid or semisolid oral drug formulation comprising a therapeutically active compound of the formula or a geometric isomer , a stereoisomer , a pharmaceutically acceptable salt , an ester thereof or a metabolite thereof , in combination with a pharmaceutically acceptable carrier .