- HIV-positive individuals on combination antiretroviral therapy are ineligible because of the potential for pharmacokinetic interactions with gemcitabine+cisplatin. In addition, these individuals are at increased risk of lethal infections when treated with marrow-suppressive therapy. Appropriate studies will be undertaken in participants receiving combination antiretroviral therapy when indicated. HIV-positive individuals on HAART will be considered eligible of they have demonstrated good compliance and have a CD4 count > 500.