Doxycycline Prophylaxis to Prevent Sexually Transmitted Infections in Women

The dPEP Kenya trial was a randomized, open-label study of 224 cisgender women aged 18–30 receiving HIV PrEP in Kisumu, Kenya. Participants were assigned to either event-driven doxycycline postexposure prophylaxis (PEP) (200 mg within 72 hours after condomless sex) or standard care. Over 12 months, 109 STIs occurred, 50 in the doxycycline-PEP group and 59 in the standard-care group (RR = 0.88; 95% CI: 0.60–1.29; P = 0.51), with no significant reduction in overall STI incidence.

Chlamydia accounted for 78% of STIs, showing a nonsignificant trend toward reduction in the doxycycline group (RR = 0.73).

All N. gonorrhoeae isolates were tetracycline-resistant (100% tet(M)+), explaining lack of efficacy.

Adherence was low, with doxycycline detected in only 29% of hair samples. No serious drug-related adverse events occurred, and no HIV infections were detected. Authors conclude that doxycycline PEP showed uncertain benefit due to poor uptake and resistance, but stress the urgent need for STI prevention strategies tailored to women, who remain disproportionately affected by STI sequelae.

The dPEP Kenya trial was a randomized, open-label study of 224 cisgender women aged 18–30 receiving HIV PrEP in Kisumu, Kenya. Participants were assigned to either event-driven doxycycline postexposure prophylaxis (PEP) (200 mg within 72 hours after condomless sex) or standard care. Over 12 months, 109 STIs occurred, 50 in the doxycycline-PEP group and 59 in the standard-care group (RR = 0.88; 95% CI: 0.60–1.29; P = 0.51), with no significant reduction in overall STI incidence.

Chlamydia accounted for 78% of STIs, showing a nonsignificant trend toward reduction in the doxycycline group (RR = 0.73).

All N. gonorrhoeae isolates were tetracycline-resistant (100% tet(M)+), explaining lack of efficacy.

Adherence was low, with doxycycline detected in only 29% of hair samples. No serious drug-related adverse events occurred, and no HIV infections were detected. Authors conclude that doxycycline PEP showed uncertain benefit due to poor uptake and resistance, but stress the urgent need for STI prevention strategies tailored to women, who remain disproportionately affected by STI sequelae.