332   Amprenavir (APV) 600 mg/Ritonavir (RTV) 100 mg BID or APV 1200 mg/RTV 200 mg QD Given in Combination with Abacavir (ABC) and Lamivudine (3TC) Maintains Efficacy in ART- Naive HIV-1-Infected Adults over 12 Weeks (APV20001).

R. Wood*¹, C. Trepo², J. M. Livrozet³, K. Arasteh⁴, J. Eron⁵, P. Kaur⁶, O. Naderer⁷, and M. B. Wire⁷.
¹Somerset Hosp., Capetown, South Africa;²Hosp. Hotel Dieu, Lyon, France;³Hosp. Edouard Herriot, Lyon, France;⁴Auguste Victoria Krankenhaus, Berlin, Germany;⁵Univ. of North Carolina, Chapel Hill;⁶Glaxo Wellcome, Greenford, UK; and⁷Glaxo Wellcome Inc., Res. Triangle Park, NC.

Background:APV C_minis significantly increased with co-administration of RTV. Data in HIV-1 infected subjects has shown APV (600 mg)/RTV (100 mg) BID and APV (1200 mg)/RTV (200 mg) QD to be optimal dosing combinations [Wood, et al, Glasgow, 2000].

Methods:Subjects who completed the randomized phase of APV20001 and continued into an open label phase with APV/ABC/3TC were allowed to switch to an APV/RTV regimen. Thirty-nine subjects opted to switch to either a BID or QD APV/RTV regimen in combination with ABC/3TC. Preliminary safety and efficacy results are for all subjects who have completed 12 weeks of therapy. No subjects who entered either APV/RTV group have discontinued therapy prematurely.

Adverse events were minimal and primarily gastrointestinal related.

Conclusion:Switching APV (1200 mg) BID to APV (600 mg)/RTV (100 mg) or APV (1200 mg)/RTV (200 mg) QD allows reduction of the total daily dose of APV (from 16 to 8 capsules daily) with maintenance of virologic suppression and minimal safety issues.