Comparison of Pharmacokinetics of Saquinavir Soft-gel Capsule (SQV-SGC) Combined with Ritonavir (RTV), SQV Hard-gel Capsule with RTV, and SQV-SGC Alone

Abstract

Saquinavir (SQV) is a human immunodeficiency virus (HIV) specific protease inhibitor. When combined with ritonavir (RTV), plasma concentration of SQV is increased. In this study, we examined pharmacokinetics of SQV soft-gel capsule (SQV-SGC) 400mg twice daily (BID) combined with RTV in HIV-1-infected patients (n=4) and compared with those of SQV hard-gel capsule (SQV-HGC) 400mg BID combined with RTV (n=12). Pharmacokinetics of SQV-SGC 1, 200mg single dose in healthy subjects (n=10) were also studied. Peak SQV concentration in plasma (C_max) and area under the plasma concentration-time curve from 0 to 8 hour (AUC_0-8h) of SQV-SGC 400mg BID combined with RTV group were higher than those of SQV-HGC 400mg BID combined with RTV group; increase of 14.7% and 25.5%, respectively. C_max and AUC_0-8h of SQV-SGC were higher than SQV-SGC 1, 200mg single dose group; increase of 3.9 fold and 8.5 fold, respectively.
These results indicated that SQV-SGC combined with RTV therapy is the most potent antiviral effect among SQV-SGC with RTV, SQV-HGC with RTV, and SQV-SGC alone.