In the treatment of bacterial vaginosis, dequalinium chloride is noninferior to metronidazole, with similarly high cure rates but better tolerability and fewer adverse events, according to a phase IV study.
Clinical cure rates 7 to 11 days after treatment initiation (visit 1) were 92.8 percent with dequalinium chloride versus 93.2 percent with metronidazole in the intention-to-treat population (n=143), and 93.1 percent versus 90.6 percent in the per-protocol population (n=111). Clinical cure was defined as the resolution of all the following criteria: abnormal vaginal discharge, fishy amine odour on vaginal fluid when exposed to 10% potassium hydroxide, and more than 20 percent clue cells on wet mount. [JAMA Netw Open 2024;7:e248661]
The treatment differences of −0.5 percentage points (95 percent confidence interval [CI], −10.8 to 9.8; p=0.002) and 2.5 percentage points (95 percent CI, −9.4 to 14.4; p=0.001) in respective populations established the noninferiority of dequalinium chloride.
Results were similar when cure rate was defined using the standard Amsel criteria, with a treatment difference of −0.1 percentage points (95 percent CI, −8.9 to 8.7; p<0.001) confirming dequalinium chloride’s noninferiority, the investigators noted.
‘Very good’ tolerability
Most patients (60 percent) rated the tolerability of dequalinium chloride as very good as opposed to only 38.9 percent for metronidazole.
Treatment-emergent adverse events (TEAEs) were documented in eight patients in the dequalinium chloride group and in 15 of those in the metronidazole group, and none of these were serious. TEAEs considered to be related to dequalinium chloride included candidiasis (n=2), vaginal infection (n=1), dysgeusia (n=1), pruritus (n=1), pharyngeal swelling (n=2), and headache (n=1). Those related to metronidazole, on the other hand, were candidiasis (n=4), burning sensation (n=2), vulvovaginal swelling (n=1), dysgeusia (n=1), dyspepsia (n=1), abdominal pain (n=1), and fatigue (n=1).
Three patients in the metronidazole group discontinued treatment due to an adverse event, one of whom had worsening of the initial findings and withdrew from the study.
Dequalinium chloride’s tolerability and safety profile may increase treatment adherence because there is no systemic absorption, and most adverse effects are local and mild, the investigators pointed out. The drug also boasts a broader spectrum of activity than clindamycin and metronidazole, potentially reducing the occurrence of other vaginal conditions such as vulvovaginal candidiasis. [BMC Res Notes 2012;5:151; Gynecol Obstet Invest 2012;73:8-15]
Finally, there have been no reports of clinically relevant resistance to dequalinium chloride throughout its 30 years in the market, they said.
“Therefore, dequalinium chloride warrants consideration as first-line empirical treatment for bacterial vaginosis due to its similar efficacy to metronidazole and clindamycin, broad spectrum, lack of resistance, tolerability, and safety,” according to the investigators.
“Unfortunately, the recurrence rate with dequalinium chloride was similar to that of antibiotics, likely due to a residual dysbiosis. Restoring the vaginal flora using probiotics after any anti-infective treatment for BV could help reduce recurrences,” they added. [Exp Ther Med 2020;20:3749-3765; Front Nutr 2022;9:938838]
Study details
The intention-to-treat analysis included 147 women (mean age 36.7 years, 98.6 percent non-Hispanic White) with bacterial vaginosis participated in the study and were randomly assigned to treatment with 10-mg vaginal tablets of dequalinium chloride (n=72) or 500-mg oral tablets of metronidazole (n=75). The baseline characteristics were similar between the treatment groups. However, fewer participants in the dequalinium chloride group than in the metronidazole group had a normal Nugent score.
The rate of clinical improvement (2 or more negative Amsel criteria at days 7–11 and 20–40 after treatment initiation) was 88.1 percent with dequalinium chloride and 92.9 percent with metronidazole. Time to resolution of clinical symptoms was comparable between the treatment groups (6.7 vs 6.5 days).
The study was limited by the short follow-up, reduced sample size, and the patient population comprising White European individuals exclusively.