450 women with BV were recruited from December 2007 to May 2010. Median age was 27 years (range 18-49); there were no differences in participant demographic or behavioural characteristics between arms. Retention rates were high, with 408 (91%) participants providing one or more sets of post-randomization data and contributing 122.5 person years of follow-up. Six-month cumulative BV recurrence rates did not differ between study arms by intention-to-treat analysis: MetPlac (26.7%, 95% CI 19.7-34.6%) MetProb (27.8%, 95% CI 20.7-35.9%) and MetClin (30.0%, 95% CI 22.9-38.0%), p>0.82.
The addition of vaginal clindamycin or a vaginal probiotic to oral metronidazole does not improve 6-month BV recurrence rates. This is the first RCT to evaluate the efficacy of combination clindamycin/metronidazole for BV treatment, and has important implications for clinical practice. Combination therapy is often used in patients with recurrent BV, but evidence to support this practice has not been available.