| 238P |
OUTCOMES OF ANTIRETROVIRAL (ARV)-EXPERIENCED PATIENTS INITIATING A SALVAGE REGIMEN
CONTAINING AMPRENAVIR AS THE PROTEASE INHIBITOR (PI)
M Loutfy, C Thompson, M Trpeski, A Rachlis, S Walmsley
University of Toronto, Toronto, Ontario
Objectives: To determine the virologic and immunologic responses to
and the tolerability of amprenavir in a cohort of ARV-experienced patients (pts).
Method: A retrospective cohort study of pts enrolled in the amprenavir
expanded access program (EAP) with at least 1 M follow-up was done. The proportion
of pts who achieved a VL <50copies/mL, the mean VL change, the CD4 count change
and the disposition of the pts at the end of follow-up was determined.
Results: 96.7% of the pts were male with a mean age of 46.2. 93.3% of
the pts were PI-experienced and 53.3% were NNRTI-experienced. The mean number
of prior ARVs was 6.9. 18 patients had genotyping prior to starting amprenavir.
The mean number of PI mutations was 5.2 and the mean number of RT mutations
was 6.3. 66.7% (20/30) were given ritonavir in addition to amprenavir as a pharmacokinetic
booster. The mean duration of follow-up was 12.1 M. The mean baseline VL was
4.56 log/mL and CD4 count was 252.0 c/mL. 25% (N=28) achieved a VL<50c/mL at
1-3M, 42.9% at 4-6 M (N=21), 45.8% (N=24) at 7-12 M and 56.3% (n=16) >12 M.
The mean decrease in VL at 1-3 M was –2.14 log, –2.46 log at 4-6 M, –2.29 log
at 7-12 M and –2.57 log at >12 M. The mean increase in CD4 count at 1-3 M was
49.3 c/mL, 84.8 c/mL at 4-6 M and 88.2 c/mL at 7-12 M. 26.7% (8/30) discontinued
amprenavir by the end of the follow-up period with 75% of the discontinuations
being due to diarrhrea, nausea or abdominal discomfort.
Conclusions: In this retrospective cohort study, amprenavir was efficacious
in ARV-experienced pts who could tolerate it. A significant number of patients
discontinued amprenavir due to adverse events, primarily gastrointestinal. This
data shows the potential utility of the investigational pro-drug of amprenavir,
GW908, which is available in a compact formulation and may be better tolerated.