PRISM study: Comparison of a nystatin-neomycin-polymyxin B combination with miconazole for the empirical treatment of infectious vaginitis.

OBJECTIVE: An empirical treatment of infectious vaginitis is justified because of its multiple etiologies, the frequent uncertainty of clinical diagnosis and limits of microbiological analysis. Our aim was to comparatively investigate nystatin-neomycin-polymyxin B combination (NNP, Polygynax®) and miconazole. PATIENTS AND METHODS: In this European multicenter, double-blind PRISM trial, participating women presenting with infectious vaginitis were randomized to receive one vaginal capsule containing either NNP for 12 days or miconazole for 3 days followed by 9 days of placebo. RESULTS: The clinical success rate was higher in the NNP group (n=302) than the miconazole group (n=309), with a difference between groups close to statistical significance (91.1% vs. 86.7%, P=0.0906). The risk of treatment failure was 36% lower in the NNP group (odds ratio, 0.64; 95% confidence interval, 0.38-1.07). Vaginal burning on Day 2 and vaginal discharge on Day 4 were significantly less intense in the NNP group than in the miconazole group (39.1 vs. 42.3, P=0.031 and 34.6 vs. 37.6, P=0.031, respectively). Adverse drug reactions were reported by 1.2% and 2.1% of patients in the NNP and miconazole group respectively, with the ratio of adverse drug reactions relative to total adverse events significantly higher in the miconazole group (20.3% vs. 6.9%, P=0.022). CONCLUSION: The widespread use of NNP for several decades and its good efficacy and safety profile, as well as the frequent diagnostic uncertainties due to the various pathogens sustain the initiation of this broad-spectrum empirical treatment in infectious vaginitis.