Effect of age on atazanavir, darunavir, raltegravir and etravirine
Trough concentrations of atazanavir, darunavir, raltegravir and efavirenz were compared in HIV-positive volunteers, grouped according to age (A: =39, B: 40-49, C: =50 years). A total of 249 samples were analysed from 134 subjects (28 ATV/r, 40 DRV/r, 47 RAL, 19 EFV).
Atazanavir mean trough concentrations were lower in group C than group A, but this was not statistically significant (1483 vs 1968 vs 1013 ng/ml, A vs B vs C). Darunavir mean concentrations were similar across the three groups (2633 vs 3077 vs 2581 ng/ml, A vs B vs C), as were raltegravir concentrations (210 vs 263 vs 177 ng/ml, A vs B vs C). Efavirenz mean concentrations were significantly higher in group C (2950 ng/ml) than in group A (2148 ng/ml) or group B (2097 ng/ml)
No linear correlation between age and concentration was found for any drug.
There are few data on the metabolism of antiretroviral drugs and it may be important to study people who are older than 60, as CYP450 activity does reduce with age.
Ref: Tommasi C et al. Pharmacological evaluation of new antiretroviral drugs in the elderly HIV-1 infected people. Tommasi C, Nicastri E, Gallo AL, et al. 11th PK Workshop, 2010. Abstract 56.