Unintended HIV-1 Transmission to a Sex Partner in a Study of a Therapeutic Vaccine Candidate.

We report a case of sexual transmission of human immunodeficiency virus (HIV) that occurred during treatment discontinuation in a therapeutic vaccine trial, following oral sex. Transmission occurred even though the index participant was an HIV/AIDS activist, particularly well informed about the risks and modalities of transmission. This case report highlights the risk of secondary transmission of HIV during cessation of treatment in HIV cure-related trials.