The antimicrobial effect of Iseganan HCl oral solution in patients receiving stomatotoxic chemotherapy: analysis from a multicenter, double-blind, placebo-controlled, randomized, phase III clinical trial.

BACKGROUND: Cytotoxic chemotherapy induces changes in the oral microflora that may cause oral and systemic infections in myelosuppressed cancer patients. These complications prompted us to assess the antimicrobial activity of a topical Iseganan HCl mouthwash vs. placebo on the aerobic and facultatively anaerobic oral flora in these patients. METHODS: Two hundred and twenty-five chemotherapy patients were recruited into a randomized, double-blind, placebo-controlled trial, conducted at multiple centers. The study compared the antimicrobial efficacy of Iseganan HCl vs. placebo (95% of the Iseganan and 97% of the control group received myeloablative chemotherapy). Iseganan HCl 9 mg/3 ml was administered as a swish and swallow solution, six times daily for 21-28 days. Microbial cultures were made before and after the daily Iseganan mouth rinse on the first and final days of chemotherapy. RESULTS: The reduction in total microbial load after the first day of treatment was statistically significant (1.59 vs. 0.18 log10 CFU for the Iseganan HCl and placebo groups, respectively, P < 0.0001). Iseganan HCl rinse had a cumulative effect demonstrated by the significant difference between the two groups on the last day of the study (i.e. completion of Iseganan daily treatment) (P < 0.05). The reduction was mainly due to decreased densities of viridans streptococci, non-hemolytic streptococci, and yeasts. The minimal inhibitory concentration (MIC) of Iseganan HCl remained the same throughout the course of treatment. CONCLUSIONS: Topical Iseganan HCl significantly reduces the total oral aerobic bacterial, streptococcal, and yeast load. Its potential as an oral antimicrobial agent in preventing these types of infections is clear.