emtricitabine--tenofovir-disoproxil-fumarate-drug-combination and Renal-Insufficiency

The use of tenofovir disoproxil fumarate (TDF) in combination with emtricitabine, prescribed for pre-exposure prophylaxis (PrEP), is highly effective at reducing incident sexually transmissible HIV infection among those at risk. TDF is associated with proteinuria, Fanconi syndrome and chronic kidney disease, and is not recommended for use in patients with an estimated creatinine clearance <60 mL min-1. There are currently no Pharmaceutical Benefits Scheme (PBS)-funded PrEP options for patients at risk of HIV infection with moderate renal impairment in Australia. This report describes the case of a patient who acquired HIV soon after PrEP was suspended due to moderate renal impairment. The various clinical and regulatory issues this case raises are discussed.

Topics: Adult; Australia; Emtricitabine, Tenofovir Disoproxil Fumarate Drug Combination; Glomerular Filtration Rate; HIV Infections; Humans; Insurance, Pharmaceutical Services; Male; Pre-Exposure Prophylaxis; Renal Insufficiency

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) significantly reduces the risk of HIV acquisition. TDF is a known nephrotoxin however, renal dysfunction from TDF is mostly reversible following discontinuation.. To describe the renal function, risk factors for renal disease and associated clinical testing practices in a cohort of PrEP patients.. A retrospective review was conducted of all PrEP patients commenced on TDF/FTC at an inner metropolitan sexual health clinic in Sydney, Australia between April 2016 and July 2017, with follow-up data obtained at 3-monthly intervals until 18 months.. 525 patients met inclusion criteria. Patients were almost exclusively male and median age was 34 years (IQR: 28 to 42). At baseline, 1.5% had an estimated glomerular filtration rate (eGFR) <70 mL/min/1.73m2. A small significant drop in eGFR of -2.5 mL/min/1.73m2 (p<0.05) occurred between PrEP commencement and the first follow-up period, followed by a progressive decline in eGFR of -0.38 mL/min/1.73m2 per month (95%CI: -0.57 to -0.20; p<0.001). Renal impairment (eGFR <70 mL/min/1.73m2) occurred in 6.5% of patients and persisted across consecutive follow-up periods in five (1.0%) patients. Patients aged ≥40 years had a greater risk of renal impairment than younger patients (HR 3.9, 95%CI: 1.8 to 8.4; p<0.001), despite similar rates of eGFR decline (p = 0.19). PrEP was discontinued in two patients (0.4%) due to renal function concerns.. PrEP use led to an initial drop in eGFR and a more gradual progressive decline subsequently, but significant renal impairment remained uncommon up to 18 months of follow-up.

Topics: Adult; Age Factors; Anti-HIV Agents; Australia; Emtricitabine, Tenofovir Disoproxil Fumarate Drug Combination; Female; Follow-Up Studies; Glomerular Filtration Rate; HIV Infections; Humans; Incidence; Kidney; Male; Middle Aged; Pre-Exposure Prophylaxis; Renal Insufficiency; Retrospective Studies; Risk Factors