1. INTRODUCTION
Globally, bacterial vaginosis is the most frequent source of vaginal infection among reproductive-aged women.1 Its approximated worldwide prevalence is high ranging from 23% to 29%.1 Clinically, it is correlated with amplified risks for adverse infectious and obstetric aftermaths, such as pelvic inflammatory disease, human immunodeficiency virus infection, sexually transmitted infections, abortion, preterm delivery, miscarriage and postoperative endometritis.2-5
The standard of care for bacterial vaginosis includes oral or vaginal antimicrobial therapies. Such therapies largely comprise clindamycin and 5-nitroimidazole derivatives (most commonly, metronidazole, tinidazole and secnidazole).6 However, these available conventional antimicrobial therapies are unsatisfactory for various factors. Such factors include the unfavorable gastrointestinal adverse events, high frequencies of vulvovaginal candidiasis, medication interaction with alcohol, insufficient targeting of the pathogenic bacterial vaginosis biofilms and high recurrence rates post treatment.7-15 Probiotics have been shown to be beneficial for bacterial vaginosis treatment when compared to placebo.16 Nevertheless, no studies are available for head-to-head comparison between probiotics and conventional antimicrobial therapies to establish the tangible therapeutic impact of probiotics for treatment of bacterial vaginosis.16 A recent report demonstrates no substantial benefit of combination metronidazole and probiotics versus monotherapy metronidazole for treatment of bacterial vaginosis.17 All in all, there is a pressing requirement to conceive alternative treatments for bacterial vaginosis.
Astodrimer gel (also known as VivaGel® or SPL7013) is a novel muco-adhesive gel that belongs to a unique class of dendrimers—highly branched nanoparticles with microbicidal actions against bacteria and viruses.18, 19 Astodrimer gel has been illustrated in healthy women to be well-endured without systemic absorption.20, 21 Thus, astodrimer gel is advantageous over conventional antibiotics that give rise to drug-related systemic adverse events. Four randomized controlled trials (RCTs) have demonstrated favorable outcomes for astodrimer gel for treatment of patients with bacterial vaginosis.22-24Mechanistically, astodrimer gel has been depicted to suppress propagation of bacterial pathogens involved in bacterial vaginosis, including Gardnerella vaginalis .22, 23 When compared to conventional antibiotics, the novel mechanism of action of astodrimer gel involves hindering bacterial attachment to vaginal epithelial cells as well as interrupting and thwarting formation of bacterial biofilms.22, 23 Thus, the potential for development of therapy resistance or relapse is minimized with astodrimer gel when compared to conventional antibiotics.
The aim of this systematic review and meta-analysis is to pool the available evidence from RCTs that examined the efficacy and safety of astodrimer gel for the treatment of patients with bacterial vaginosis.