Determination of abacavir, amprenavir, didanosine, efavirenz, nevirapine, and stavudine concentration in human plasma by MALDI-TOF/TOF

The interest in therapeutic drug monitoring (TDM) of antiretroviral drugs has grown significantly since highly active antiretroviral therapy (HAART) became a standard of care in clinical practice. TDM is useful to determine the best dosage regimen adapted to each patient. Here, we apply MALDI-TOF/TOF technology to quantify abacavir, amprenavir, didanosine, efavirenz, nevirapine, and stavudine in the plasma of HIV-infected patients, by standard additions analysis. Regression of standard additions was linear over the whole anti-HIV concentration range explored (1.00 × 10−2–1.00 pmol/μL). The absolute recovery ranged between 80% and 110%. Values of the drug concentration determined by MALDI-TOF/TOF were in the range of 1.00 × 10−2–1.00 pmol/μL. The limit of quantification value was 1.00 × 10−2 pmol/μL for abacavir, amprenavir, didanosine, efavirenz, nevirapine, and stavudine.