Lactin-V Studied for Prevention of Bacterial Vaginosis Recurrence

bacterial vaginosis
bacterial vaginosis
A randomized trial was conducted to assess the effect of Lactin-V vs placebo following metronidazole treatment for bacterial vaginosis.

The use of Lactobacillus crispatus CTV-05 (Lactin-V) after treatment with vaginal metronidazole was found to significantly lower the incidence of recurrence of bacterial vaginosis at 12 weeks compared with placebo, according to data from a randomized trial published in The New England Journal of Medicine.

There is a high incidence of recurrence of bacterial vaginosis, suggesting the need for new treatments. In a randomized, double-blind, placebo-controlled, phase 2b trial, the ability of Lactin-V to prevent the recurrence of bacterial vaginosis was evaluated ( Identifier: NCT02766023).

In the trial, 152 women were randomly assigned to the Lactin-V group and 76 to the placebo group. Of these, 88% and 84% could be evaluated for the primary outcome in the Lactin-V and placebo groups, respectively. Recurrence of bacterial vaginosis by week 12 in the intention-to-treat population occurred in 30% of the Lactin-V group and 45% of the placebo group (risk ratio after multiple imputation for missing responses, 0.66; 95% CI 0.44-0.87; P =.01). By week 24, the risk ratio for occurrence, again calculated with multiple imputation for missing responses, was 0.73 (95% CI 0.54-0.92). L crispatus CTV-05 was detected in 79% of participants in the Lactin-V group at week 12. The percentage of participants with at least one Lactin-V- or placebo-related adverse event by week 24 did not differ significantly between the groups. Furthermore, the percentage of participants with local or systemic adverse events was similar between groups.

The investigators found that, “the use of Lactin-V after treatment with vaginal metronidazole for bacterial vaginosis resulted in a significantly lower incidence of recurrence of bacterial vaginosis at 12 weeks than placebo, and the benefit appeared to persist through week 24.” They also note that adherence to the assigned treatment was high. However, 14% of enrolled women were ineligible for the analysis of the primary outcome, which was higher than the assumed percentage of 10% that was used to estimate the sample size. The results of multiple imputation analyses and several sensitivity analyses did produce findings consistent with those of the complete-case analysis. According to investigators, further studies should now be considered to assess the long-term sustainability of colonization and prevention of bacterial vaginosis.


Cohen CR, Wierzbicki MR, French AL, et al. Randomized trial of Lactin-V to prevent recurrence of bacterial vaginosis. N Engl J Med. 2020;382:1906-1915.