Serum Nevirapine and Efavirenz Concentrations and Effect of Concomitant Rifampicin in HIV Infected Children on Antiretroviral Therapy.
Loading...
Date
2011-12
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Objective: To determine factors affecting serum levels of
Efavirenz and Nevirapine and analyze the effect of
Rifampicin on Nevirapine drug levels.
Methods: A cross-sectional study was conducted on 30
HIV infected children on Antiretroviral therapy (ART) with
Nevirapine or Efavirenz. Patients on simultaneous
Rifampicin and Nevirapine were given higher doses of
Nevirapine with regular monitoring of liver function tests.
Trough levels (before morning dose of Nevirapine) and
levels after 2 hours of administration of Nevirapine and
levels of Efavirenz were assessed using HPLC and were
checked to see if they fall within the therapeutic range.
Results: Thirty patients (14 males) were enrolled in the
study with 20 on Nevirapine and 10 (33.3%) on Efavirenz.
Seven (23.3%) patients were simultaneously taking
rifampicin. The mean Nevirapine dose given to the
patients was 350.9±59.8mg/m2/day (on simultaneous
rifampicin) and 309.2±54.6mg/m2/day (not on concurrent
rifampicin). Thirteen (81.3%) of the 16 patients with trough
Nevirapine had values in the normal range, 1 (6.3%) had
low Nevirapine trough levels and 2 (12.5%) had high
Nevirapine trough levels. Of the post 2 hours Nevirapine
levels, 1 (5%) had low levels and 3 (15%) had high
Nevirapine blood levels. Factors like age (P=0.4,
P=0.4087), nourishment (P=0.2679, P=0.4132), ART
combination (P=0.4199, P=0.4132), form of the drug
(tablet/syrup) (P=0.1964, P=0.4696) or if it was being
given as single or in a fixed dose combination (P=0.4179,
P=0.4696) and even concurrent rifampicin administration
(P=0.284, P=0.472) did not significantly affect the trough
and post 2 hours Nevirapine values, respectively. All the
five patients being given concurrent rifampicin had normal
trough and post 2 hours levels of Nevirapine. The
Efavirenz drug levels were 1.9±1.1 g/mL. Of the 10
patients on Efavirenz, 2 (20%) had high and 1 (10%) had
low blood levels.
Conclusion: Concurrent Rifampicin administration does
not alter blood levels of Nevirapine; provided the dose of
Nevirapine is increased by 20-30%. Formulation of drugs
does not alter the blood levels provided drug administered
is in the recommended dose.
Description
Keywords
Anti-retroviral, Drug levels, Efavirenz, Rifampicin therapy, Nevirapine
Citation
Shah Ira, Swaminathan Soumya, Ramachandran Geetha, Kumar A K Hemanth, Goray Apurva, Chaddha Udit, Tayal Swati, Lala Mamatha. Serum Nevirapine and Efavirenz Concentrations and Effect of Concomitant Rifampicin in HIV Infected Children on Antiretroviral Therapy. Indian Pediatrics. 2011 December; 48(12): 943-947.