Once-daily regimen of saquinavir, ritonavir, didanosine, and lamivudine in HIV-infected patients with standard tuberculosis therapy (TBQD Study).
OBJECTIVE
To assess the efficacy and safety of a once-daily regimen with didanosine, lamivudine, saquinavir, and low-dose ritonavir in antiretroviral (ARV)-naive patients with tuberculosis treated with rifampin and the influence of rifampin on plasma trough concentration (Ctrough) of saquinavir.


METHODS
Single-arm, prospective, multicenter, open-label pilot study, including 32 adult ARV-naive subjects with HIV infection and tuberculosis under standard treatment that included rifampin (600 mg q.d.) and isoniazid (300 mg q.d.). After 2 months of tuberculosis treatment, patients were started on once-daily ARV therapy, consisting of didanosine, lamivudine, ritonavir (200 mg), and saquinavir soft gel capsules (1600 mg). HIV RNA level, CD4 cell count, clinical and laboratory toxicity, and saquinavir Ctrough during and after antituberculosis therapy were analyzed.


RESULTS
After 48 weeks of follow-up, 20 of 32 patients (62.5%; 95% CI: 45.8% to 79.2%) in the intent-to-treat population and 20 of 28 (71.4%; 95% CI: 54.4% to 88.4%) in the on-treatment population had an HIV RNA level <50 copies/mL. Treatment tolerance was acceptable in all patients except for 2 with biologic hepatic toxicity leading to discontinuation. Seven patients had virologic failure. In 10 patients (36%), saquinavir Ctrough was <0.05 microg/mL during tuberculosis therapy and 5 of them had virologic failure. The median saquinavir Ctrough was 44% lower (interquartile range: 19% to 71%) with coadministration of rifampin than without.


CONCLUSIONS
The combination of didanosine, lamivudine, saquinavir, and ritonavir may be a useful treatment regimen for patients with tuberculosis in whom a once-daily protease inhibitor-containing regimen is considered indicated. Nevertheless, on the basis of pharmacokinetic profile the dose of 1600/200 mg of saquinavir/ritonavir cannot be recommended. Further studies with higher doses of saquinavir (2000 mg) boosted with ritonavir are warranted.
Ribera
Esteban
E
Infectious Diseases Service, Hospital Universitari Vall d'Hebron, Barcelona, Spain. eribera@vhebron.net
Azuaje
Carlos
C
Lopez
Rosa M
RM
Domingo
Pere
P
Soriano
Alex
A
Pou
Leonor
L
Sánchez
Paquita
P
Mallolas
Josep
J
Sambea
Maria Antonia
MA
Falco
Vicenç
V
Ocaña
Imma
I
Lopez-Colomes
Josep Lluis
JL
Gatell
Josep M
JM
Pahissa
Albert
A
D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage* / Q000009:adverse effects; D000995:Antitubercular Agents / Q000009:adverse effects / Q000627:therapeutic use*; D056486:Chemical and Drug Induced Liver Injury; D016049:Didanosine / Q000008:administration & dosage*; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000150:complications* / Q000188:drug therapy* / Q000378:metabolism; D017320:HIV Protease Inhibitors / Q000008:administration & dosage; D006801:Humans; D019259:Lamivudine / Q000008:administration & dosage*; D008297:Male; D010865:Pilot Projects; D019438:Ritonavir / Q000008:administration & dosage*; D019258:Saquinavir / Q000008:administration & dosage* / Q000493:pharmacokinetics; D013030:Spain; D016896:Treatment Outcome; D014376:Tuberculosis / Q000150:complications* / Q000188:drug therapy*
D019380:Anti-HIV Agents; D000995:Antitubercular Agents; D017320:HIV Protease Inhibitors; D019259:Lamivudine; D016049:Didanosine; D019258:Saquinavir; D019438:Ritonavir