Saquinavir [‘Invirase’; Roche] was the first protease inhibitor to be launched for the treatment of HIV infection. Extensive clinical experience has shown it to be an effective and well tolerated component of combination anti-HIV therapy, delaying disease progression and prolonging survival in HIV-infected individuals. Recently, a new soft gelatin capsule formulation of saquinavir has been developed [saquinavir-SGC; ‘Fortovase’] which, at the recommended dosage, achieves plasma saquinavir concentrations approximately 8- to 10-fold higher than those attained with ‘Invirase’, the conventional hard gel formulation. Since the activity of saquinavir is directly related to plasma drug concentrations, it is anticipated that this new formulation will help optimise the antiviral and clinical benefits of saquinavir. The first data on saquinavir-SGC were presented at the 37th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) [Toronto, Canada; September 1997] and at the 6th European Conference on Clinical Aspects and Treatment of HIV [Hamburg, Germany; October 1997].