Investigation of the solvent-dependent photolysis of a nonnucleoside reverse-transcriptase inhibitor, antiviral agent efavirenz

Methods optimization and application: Solid phase extraction, Ultrasonic extraction and Soxhlet extraction for the determination of antiretroviral drugs in river water, wastewater, sludge, soil and sediment

The continuous release of antiretroviral drugs into the environmental has resulted in the interest to assess their occurrence in various environmental matrices. Their presence has led to antiretroviral drugs being considered the pollutants of concern due to their possible alterations of the ecosystem as well as the antiviral resistance that may develop upon their unintentional consumption. Therefore, in this work, solid phase extraction (SPE), ultrasonic extraction (UE), Soxhlet extration (SE) and liquid chromatography coupled to photodiode array detector (LC-PDA) methods have been optimized and validated. They were then applied for the simultaneous determination of abacavir, nevirapine and efavirenz antiretroviral drugs in wastewater, river water, sludge, soil and sediments. The percentage recoveries ranged from 71% to 112% for SPE, 88 - 108% for SE and 61 - 104% for UE. Good precision with a relative standard deviation less than 20% in all compounds for all methods was obtained. The LODs and LOQs ranged between 0.68 and 0.77 µg/L and 2.1-2.4 µg/L for SPE; 0.8-0.9 µg/kg and 2.3-2.8 µg/kg for SE and 1.6-2.8 µg/kg and 4.9 - 7.0 µg/kg for UE, respectively. The concentrations ranged from <lod - 102 µg/L, <lod - 814 µg/L, and <lod - 6759 µg/L, <lod - 138 µg/g, <lod - 98.9 µg/g, in river water, wastewater, sludge, soil and sediment samples, respectively. Abacavir was dominant in water while efavirenz was dominant in soil/sediments. The results showed that SE is more sensitive and more accurate than UE, hence it can be recommended for routine analysis despite its longer extraction times. The percentage removal efficiency ranged from 44% to 87% for nevirapine, 6-53% for efavirenz, and 75-91% for abacavir which indicates that these compounds were not completely removed during the WWTP processes, hence they ended up in river waters.

Anti-retroviral drugs induced photosensitivity may be two culprits in mixed formulation, a case report and literature review

Although the most frequent presentation of adverse drug events amongst HIV- infected individuals is skin rash, photosensitivity is uncommon. We herein described an HIV-infected female who presented with photo-distributed annular target-like eruptions and small tense blisters. Our patient had objectively reduced erythemal thresholds on broadband UV phototesting, to both UVA and UVB. Resolution of the abnormal responses on retesting undertaken after cessation of the tenofovir disoproxil fumarate and efavirenz in mixed formulation for five months confirmed a diagnosis of drug-induced photosensitivity. Given the preferred first-line anti-retroviral therapy which usually contains both TDF and EFV, photoprotection from broad-band ultraviolet wavelengths should be emphasized for the patients receiving this antiretroviral regimen.