F7/3 - ARE THOSE FAILING FIRST-LINE HAART THERAPY CONTAINING NELFINAVIR LESS LIKELY TO FAIL SECOND-LINE PI-CONTAINING HAART?

9^TH EUROPEAN AIDS CONFERENCE (EACS)
1^st EACS RESISTANCE & PHARMACOLOGY WORKSHOP

October 25 - 29, 2003 Warsaw, Poland

7.4 Treatment Failure and Salvage Therapy

F7/3 - ARE THOSE FAILING FIRST-LINE HAART THERAPY CONTAINING NELFINAVIR LESS LIKELY TO FAIL SECOND-LINE PI-CONTAINING HAART?

* Ghani A.G.¹, Kwong G.¹, Le Fevre A.M.¹, Gras L.², van Sighem A.², de Wolf F.², Anderson R.M.¹

(1) Department of Infectious Disease Epidemiology, Imperial College London, UK,² HIV Monitoring Foundation, Amsterdam, The Netherlands

Objective: The unique genotypic resistance profile of nelfinavir could increase the likelihood of success for subsequent PI-containing regimens. We compared the effectiveness of second PI-containing HAART (PI-HAART) regimens in those failing initial PI-HAART containing nelfinavir to those failing other PI-HAART.

Methods: Data on the virological response of 1,111 patients from the U.S. (HIV Insight) and the Netherlands (ATHENA) who initiated PI-HAART (defined as 1 or 2 PIs and 2 NRTIs) and switched to a second PI-HAART following virologic failure were analysed. Initial success of the second PI-HAART was measured as the time taken for viral load to fall below 500 copies/ml and the subsequent time to rebound (two consecutive measurements >500 copies/ml) in those achieving viral suppression. Comparisons were undertaken using proportional hazards models, adjusting for age, sex, risk group, country, calendar year of first and second therapy, baseline HIV-1 RNA, baseline CD4+ T-cell count, duration of first therapy, duration of break between first and second therapies and PI-component of second therapy.

Results: No significant difference was found in the time to viral suppression between those whose first PI-HAART contained nelfinavir (n=93) or another PI (n=1018) (HR 1.0, 95% CI 0.71-1.5, p=0.86). In 522 patients (nelfinavir n=44, other n=478) achieving viral suppression, no significant difference was found in the subsequent time to rebound between the two groups (HR 1.6, 95% CI 0.54-4.6, p=0.40).

Conclusions: Results suggest that the unique genotypic resistance of nelfinavir may be of little benefit to subsequent PI-containing regimens. Further analyses are required to confirm these findings.

Presenting Author: Dr Azra Ghani, Department of Infectious Disease Epidemiology, Imperial College London, Norfolk Place, W21PG, London, United Kingdom, Phone: +44 2075943284

031025
36