Nonhormonal vaginal gel exhibits significant contraception in Phase 3 AMPOWER Clinical Trial
According to findings from a post hoc analysis of the registrational phase 3 AMPOWER trial, use of Phexxi® (lactic acid, citric acid, potassium bitartrate) vaginal gel prevented 99% of pregnancies per act of intercourse.
In the analysis, Phexxi prevented 99% of pregnancies per act of intercourse. This was based on 101 pregnancies (n=1182) over 24,289 acts of intercourse with typical use in 1,182 women. The per-act-of-intercourse pregnancy risk of 0.415% was not statistically tested in AMPOWER and, therefore, is not in the U.S. Prescribing Information (USPI) approved by the FDA.
"Providing data showing how Phexxi performs on-demand to prevent pregnancy per act of intercourse helps women and their doctors better understand Phexxi and the value its innovation adds to the armamentarium of choice," said Saundra Pelletier, Chief Executive Officer of Evofem.
Earlier this year, the Journal of Sexual Medicine published a post hoc analysis of an exploratory endpoint showing that 88.7% of women using Phexxi in AMPOWER improved or maintained their sex life. Additionally, last month, Evofem presented a post hoc analyses at the American College of Obstetricians and Gynecologists annual clinical and scientific meeting showing that incidences of urinary tract infections in women who used Phexxi in AMPOWER were less compared to the general population (5.8% vs 11.0%, respectively).
The FDA approved Phexxi in May of 2020 based on the registrational AMPOWER trial, which enrolled 1,349 women in the U.S., as well as combined safety data from AMPOWER and a previous Phase 3 trial, AMP-001, which together provided more than 19,000 cycles of exposure in 2,804 women from the U.S. In AMPOWER, Phexxi demonstrated contraceptive efficacy, with a 7-cycle cumulative pregnancy rate of 13.7% (95% CI: 10.0%, 17.5%) with typical use and 6.67% with perfect use (95% CI: 4.61%, 8.73%), corresponding to an efficacy rate of 86.3% and 93.3%, respectively, in preventing pregnancy. Evofem has not studied Phexxi's efficacy and safety in comparison to other contraceptives.
Phexxi's mechanism of action through vaginal pH modulation results in the immobilization of spermatozoa by maintaining the normally low vaginal pH, even in the presence of semen. Phexxi is not a spermicide and does not contain surfactants such as nonoxynol-9, which causes irreversible membrane alterations of the sperm cells thereby damaging the sperm cell membranes and killing the sperm cells.
