Laboratory Testing of a Cohort of Commercially Insured Users of HIV Preexposure Prophylaxis in the United States, 2011–2015

: To ensure the health and safety of persons taking antiretroviral medication as preexposure prophylaxis (PrEP) against human immunodeficiency virus (HIV) infection, Centers for Disease Control and Prevention guidelines recommend initial and follow-up laboratory testing. We assessed the rates of recommended testing, using a commercial insurance claims database. Before taking PrEP, 45% of users were tested for HIV, 55% for syphilis, 43% for chlamydia/gonorrhea, and 38% for hepatitis B, and 31% had their creatinine level measured. By 6 months after PrEP initiation, 38% were tested for HIV, 49% for syphilis, and 39% for chlamydia/gonorrhea, and 37% had their creatinine level measured. Although laboratory testing was less frequent than recommended, testing rates increased over the study period.