A novel, investigational vaginal pH regulator (VPR) – a nonhormonal, water-based, petroleum-free contraceptive vaginal gel – improved genitourinary (GU) side effects and sexual satisfaction in women who are at risk of pregnancy but are not aiming to conceive, interim findings from the phase III AMPOWER* trial show.
The single-arm, open-label study included 1,330 monogamous, sexually active women (mean age 27.7 years) who had normal menstrual cycles. Participants were instructed to use VPR exclusively, without any other contraceptive method**, during the study. VPR should be administered intravaginally up to an hour before each vaginal intercourse episode. The primary endpoint was cumulative pregnancy rate over seven cycles of use.
In the safety analysis, the most common adverse events (AEs) reported were vaginal burning (20 percent) and itching (11.2 percent). The rates dropped over time for both burning (11.2, 4.2, and 1.4 percent for cycles 0, 3, and 7, respectively) and itching (4.5, 1.1, and 0.3 percent, respectively). [ACOG 2020, abstract 19I]
Compared with the general cohort, the rates of burning and itching were higher among women who had GU infections on-study (n=77; 32.5 percent and 22.1 percent, respectively) and those who had a history of bacterial vaginosis (n=245; 21.6 percent and 12.7 percent, respectively).
The rates of burning and itching during intercourse were relatively lower among women who used VPR once daily (2.1 percent [burning] and 0.7 percent [itching]) compared with those who used it more than twice daily (4.6 percent and 1.0 percent, respectively).
The low rates in GU symptoms, together with a low discontinuation rate (1 percent), underscore the safety of VPR use, said the researchers.
In an exploratory analysis, sexual satisfaction/function was evaluated via questionnaires administered at baseline (cycle 0) and at the 3rd, 4th, and 5th visits. [ACOG 2020, abstract 32I]
At visit 3, more women reported that VPR positively impacted their sex life as opposed to the previous contraceptive method/s that they used 4 weeks prior to enrolment (44.5 percent vs 16.9 percent).
The fraction of women who had no difficulty in maintaining lubrication during intercourse was also greater by visit 3 than at baseline (82.5 percent vs 73.9 percent).
More women saw improvements in other sexual function measures by visit 3 compared with baseline, such as vaginal dryness (79.9 percent vs 59.8 percent), lack of sexual desire/interest (71.2 percent vs 61.9 percent), vaginal tightness (70.5 percent vs 58.5 percent), pain during intercourse (80.8 percent vs 70.5 percent), anxiety about sexual performance (85.4 percent vs 80.3 percent), and inability to orgasm (69.9 percent vs 60.8 percent).
“[The findings at visit 3 suggest that] sexual satisfaction/function [improved] after just one cycle of use with VPR compared with baseline,” said the researchers.
Taken together, these findings support the initial findings showing the efficacy and safety of VPR in preventing pregnancy. [Fertil Steril 2019;doi:10.1016/j.fertnstert.2019.07.162] “[VPR] provides women with an important new, nonhormonal, woman-controlled contraceptive option,” they said.