LACTIN-V reduces recurrent bacterial vaginosis risk following cure with antibiotics

Key takeaways:

• Recurrent bacterial vaginosis (BV) impacts quality of life, but treatment is currently limited to repeated courses of antibiotics.
• Among women who were cured of BV with antibiotic treatment, LACTIN-V significantly reduced the risk for BV recurrence.
• Women who were clinically cured of BV with antibiotics had higher concentrations of Lactobacillus colonization.

A live biotherapeutic product significantly reduced the risk for recurrent BV in women who were clinically cured after initial antibiotic treatment, according to research presented at the Infectious Diseases Society for Obstetrics and Gynecology Annual Meeting.

BV, a vaginal infection that affects many women worldwide, is caused by the overgrowth of harmful pathogens and a lack of the Lactobacillus bacterium, according to Anke Hemmerling, MD, PhD, MPH, project director of the University of California, San Francisco, Bixby Center for Global Reproductive Health. The condition is most commonly associated with vaginal odor and discharge but is also related to pelvic inflammatory disease and preterm birth, and it increases the risk for sexually transmitted infections.

“BV negatively impacts women’s quality of life and is a serious threat to women’s health,” Hemmerling told Healio. “Many providers are as frustrated as the women they serve about the limitations of standard antibiotic treatments.”

A randomized controlled study published in The New England Journal of Medicine in 2020 showed that using L. crispatus CTV-05, or LACTIN-V, following treatment with metronidazole significantly reduced the rate of bacterial vaginosis recurrence in women compared with placebo. However, in the intent-to-treat population, 30% of women who used LACTIN-V had a BV recurrence by 12 weeks.

In a post hoc analysis of that study, Hemmerling and colleagues evaluated 228 women aged 18 to 45 years who were diagnosed with BV and completed a treatment regimen of 5-day vaginal metronidazole 0.75%, and then underwent a clinical test of cure. The women were then randomly assigned LACTIN-V or placebo over 11 weeks, followed by a 13-week dosing phase. Levels of L crispatus CTV-05 — “a strain native to the human vagina,” Hemmerling explained — were measured using polymerase chain reaction assays.

The researchers found that “antibiotics work well to treat BV” but “only for a short period of time.”

By enrollment, 88% achieved clinical cure — including those about to undergo treatment with LACTIN-V and women in the placebo arm. Among women who received LACTIN-V, the risk ratio for BV occurrence after 12 weeks was 0.56 (95% CI, 0.35-0.77) following a clinical cure with antibiotics compared with 1.34 (95% CI, 0.47-2.23) following antibiotic treatment failure. At 24 weeks, the risk ratio was 0.67 (95% CI, 0.48-0.87) among women with a clinical cure and 1.12 (95% CI, 0.57-1.68) among those who failed antibiotic therapy.

The researchers also observed that among women who achieved clinical BV cure “reached significantly higher levels of detectable concentrations” of L. crispatus CTV-05.

“As a next step in our research, we want to better understand what kind of bacteria tend to prevail in the vaginal microbiome of some women even after antibiotic treatment, what kind of bacteria are associated with better Lactobacillus CTV-05 colonization, and which of them lead to BV recurrence,” Hemmerling said. “Also, we are planning a confirmatory phase 3 trial to collect more effectiveness data and gain FDA approval for LACTIN-V.”

References:

• Cohen CR, et al. N Engl J Med. 2020;doi:10.1056/NEJMoa1915254.
• Hemmerling, A, et al. Response to antibiotic treatment of bacterial vaginosis predicts the effectiveness of LACTIN-V (Lactobacillus crispatus CTV-05) in the prevention of recurrent disease. Presented at: Infectious Diseases Society for Obstetrics and Gynecology Annual Meeting; Aug. 4-6, 2022; Boston.