And women will need easy access to the shots every eight weeks,which must be given by a medical professional. During the clinical trial, because of restrictions introduced during the pandemic, “there was a scramble to make sure that these women could continue to get their injections on time,” Dr. Smith of ViiV Healthcare said. The trial researchers sent transportation for the women and managed to retain 98 percent of the participants, she said.
The randomized, double-blind clinical trial was conducted by the H.I.V. Prevention Trials Network, an international collaborative funded by the National Institutes of Health. The trial compared the injected drug, called cabotegravir, with Truvada in 3,223 participants in 20 sites across seven countries in sub-Saharan Africa.
Of the women who received Truvada, 34 became infected with H.I.V. during the trial, compared with just four of the women receiving the injections; two of those four women had stopped taking the injections, Dr. Smith said.
After an interim analysis showed that the long-acting injection was 89 percent more effective than Truvada, an independent data safety monitoring board recommended that the trial be stopped early.
“I am extremely excited about the findings of this study, and I have to admit that I was on razor’s edge waiting for these results,” said Dr. Monica Gandhi, an H.I.V. expert at the University of California, San Francisco, who was not involved in the trial.
The drug does not need to be refrigerated, so mobile clinics and community centers can offer it to women or bundle it with injectable birth control, Dr. Gandhi said.
A previous trial tested the drug in nearly 4,600 cisgender men and transgender women who have sex with men and found it to be 66 percent more effective than Truvada in that population. That trial was expected to continue into 2022, but was stopped in May for similar reasons.