Pharmacokinetics of Raltegravir in HIV-Infected Patients on Rifampicin-Based Antitubercular Therapy.

BACKGROUND: Rifampicin (RIF) induces UGT1A1, an enzyme involved in raltegravir (RAL) elimination, thereby potentially lowering RAL exposure. We examined the pharmacokinetics of RAL in human immunodeficiency virus (HIV)-infected patients on RIF-based antitubercular therapy in the French National Agency for HIV/AIDS and Viral Hepatitis Research 12 180 Reflate Tuberculosis trial. METHODS: Patients started RAL in combination with tenofovir disoproxil fumarate and lamivudine after initiation of RIF (10 mg/kg/day). In arm 1 (n = 21), they received 400 mg RAL twice daily; in arm 2 (n = 16), they received RAL 800 mg twice daily initially then 400 mg twice daily 4 weeks after RIF discontinuation. Pharmacokinetic sampling was performed over 12-hour periods, 4 weeks after initiation of RAL together with RIF (period 1), 4 weeks after RIF discontinuation (period 2), and after the RAL dose reduction in arm 2 (period 3). RESULTS: In arm 1, the geometric mean ratio (GMR) between period 1 and period 2 was 0.94 (90% confidence interval [CI], .64-1.37) for the 12-hour area under the time-concentration curve (AUC0-12), and 0.69 (90% CI, .42-1.13) for the concentration at 12 hours (C12). In arm 2, the corresponding GMRs were 0.75 (90% CI, .48-1.17) and 1.10 (90% CI, .61-2.00) for period 1 vs period 2, and 1.10 (90% CI, .78-1.55) and 1.68 (90% CI, .88-3.23) for period 1 vs period 3. CONCLUSIONS: The double dose of RAL overcompensated for RIF induction, but the standard dose was associated with only small decreases in AUC0-12 and C12 during RIF coadministration, warranting further evaluation in patients with HIV/tuberculosis coinfection. CLINICAL TRIALS REGISTRATION: NCT0082231.

Intensification of antiretroviral therapy through addition of enfuvirtide in naive HIV-1-infected patients with severe immunosuppression does not improve immunological response: results of a randomized multicenter trial (ANRS 130 Apollo).

We studied whether addition of enfuvirtide (ENF) to a background combination antiretroviral therapy (cART) would improve the CD4 cell count response at week 24 in naive patients with advanced HIV disease. ANRS 130 Apollo is a randomized study, conducted in naive HIV-1-infected patients, either asymptomatic with CD4 counts of <100/mm(3) or stage B/C disease with CD4 counts of <200/mm(3). Patients received tenofovir-emtricitabine with lopinavir-ritonavir (LPV/r) or efavirenz and were randomized to receive ENF for 24 weeks (ENF arm) or not (control arm). The primary endpoint was the proportion of patients with CD4 counts of ≥ 200/mm(3) at week 24. A total of 195 patients were randomized: 73% had stage C disease, 78% were male, the mean age was 44 years, the median CD4 count was 30/mm(3), and the median HIV-1 RNA load was 5.4 log(10) copies/ml. Eighty-one percent of patients received LPV/r. One patient was lost to follow-up, and eight discontinued the study (four in each arm). The proportions of patients with CD4 counts of ≥ 200/mm(3) at week 24 were 34% and 38% in the ENF and control arms, respectively (P = 0.53). The proportions of patients with HIV-1 RNA loads of <50 copies/ml were 74% and 58% at week 24 in the ENF and control arms, respectively (P < 0.02), and the proportion reached 79% in both arms at week 48. Twenty (20%) and 12 patients (13%) in the ENF and control arms, respectively, experienced at least one AIDS event during follow-up (P = 0.17). Although inducing a more rapid virological response, addition of ENF to a standard cART does not improve the immunological outcome in naive HIV-infected patients with severe immunosuppression.