Characterization of Human Immunodeficiency Virus (HIV) Infections in Women Who Received Injectable Cabotegravir or Tenofovir Disoproxil Fumarate/Emtricitabine for HIV Prevention: HPTN 084

J Infect Dis. 2022 May 16;225(10):1741-1749. doi: 10.1093/infdis/jiab576.


Background: HIV Prevention Trials Network 084 demonstrated that long-acting injectable cabotegravir (CAB) was superior to daily oral tenofovir (TFV) disoproxil fumarate (TDF)/emtricitabine (FTC) for preventing human immunodeficiency virus (HIV) infection in sub-Saharan African women. This report describes HIV infections that occurred in the trial before unblinding.

Methods: Testing was performed using HIV diagnostic assays, viral load testing, a single-copy RNA assay, and HIV genotyping. Plasma CAB, plasma TFV, and intraerythrocytic TFV-diphosphate concentrations were determined by liquid chromatography-tandem mass spectrometry.

Results: Forty HIV infections were identified (CAB arm, 1 baseline infection, 3 incident infections; TDF/FTC arm, 36 incident infections). The incident infections in the CAB arm included 2 with no recent drug exposure and no CAB injections and 1 with delayed injections; in 35 of 36 cases in the TDF/FTC arm, drug concentrations indicated low or no adherence. None of the cases had CAB resistance. Nine women in the TDF/FTC arm had nonnucleoside reverse-transcriptase inhibitor resistance; 1 had the nucleoside reverse-transcriptase inhibitor resistance mutation, M184V.

Conclusions: Almost all incident HIV infections occurred in the setting of unquantifiable or low drug concentrations. CAB resistance was not detected. Transmitted nonnucleoside reverse-transcriptase inhibitor resistance was common; 1 woman may have acquired nucleoside reverse-transcriptase inhibitor resistance from study drug exposure.

Keywords: Africa; HIV; HPTN 084; TDF/FTC; cabotegravir; injectable; long-acting; preexposure prophylaxis; prevention; women.

Publication types

  • Clinical Trial

MeSH terms

  • Anti-HIV Agents* / therapeutic use
  • DNA-Directed RNA Polymerases
  • Diketopiperazines
  • Emtricitabine / therapeutic use
  • Female
  • HIV
  • HIV Infections* / drug therapy
  • HIV Infections* / prevention & control
  • Humans
  • Nucleosides / therapeutic use
  • Pre-Exposure Prophylaxis*
  • Pyridones
  • Reverse Transcriptase Inhibitors / therapeutic use
  • Tenofovir / therapeutic use


  • Anti-HIV Agents
  • Diketopiperazines
  • Nucleosides
  • Pyridones
  • Reverse Transcriptase Inhibitors
  • Tenofovir
  • DNA-Directed RNA Polymerases
  • Emtricitabine
  • cabotegravir