Promising Results from Phase-II Clinical Trial of New Antibiotic for Gonorrhea
Understanding Gonorrhea
Gonorrhea is a sexually transmitted disease characterized by a bacterial infection that spreads through unprotected oral, vaginal, or anal sex with an infected partner. Pregnant women with gonorrhea can transmit the infection to their newborns, potentially causing blindness or severe infections.
The Rising Threat of Drug-Resistant Gonorrhea
The prevalence of drug-resistant gonorrhea is escalating globally, including in the United States. According to the World Health Organization, approximately 78 million individuals are currently infected with gonorrhea. The Centers for Disease Control and Prevention reported a nearly 19 percent increase in annual gonorrhea cases in the U.S. in 2016 compared to the previous year, with young people aged 15 to 24 accounting for 70 percent of new infections. The most significant rise in cases occurred among men who have sex with men.
Symptoms of gonorrhea typically manifest within weeks of exposure, although some individuals may remain asymptomatic. Men may first notice a burning sensation during urination, which can progress to increased urgency, a thick yellowish-green discharge, and testicular pain. Women face a higher risk of long-term complications, as gonorrhea symptoms can resemble common yeast or bacterial infections.
Current Treatment and Management Options
Gonorrhea is primarily treated with a short course of antibiotics. However, the bacteria have increasingly developed resistance to these medications. Currently, it is estimated that 30 percent of new gonorrhea infections are resistant to at least one antibiotic, making drug-resistant gonorrhea a significant public health concern.
Introduction of Zoliflodacin: A New Oral Antibiotic
A recent study published in The New England Journal of Medicine evaluated the efficacy of a novel antibiotic, Zoliflodacin, for treating uncomplicated gonorrhea. Developed by the Global Antibiotic Research and Development Partnership and Entasis Therapeutics, Zoliflodacin works by inhibiting DNA synthesis in a distinct manner compared to existing antibiotics.
To assess the effectiveness and safety of Zoliflodacin for urogenital gonorrhea treatment, researchers conducted a multicenter, randomized phase-II trial at various sexual health clinics from November 2014 to December 2015. The study involved 167 men and 12 non-pregnant women aged 18 to 55 who presented with symptoms of uncomplicated urogenital gonorrhea, untreated gonorrhea, or recent sexual contact with an infected individual. Participants were randomly assigned to receive either a single 2 or 3-gram dose of oral Zoliflodacin or a 500-milligram dose of the conventional injectable antibiotic ceftriaxone.
Clinical Trial Outcomes
The study revealed that Zoliflodacin effectively blocks proteins necessary for the gonorrhea bacteria’s replication. After six days of treatment, 48 out of 49 participants receiving the 2-gram dose and all 47 participants receiving the 3-gram dose were successfully cured of urogenital gonorrhea. A total of 21 adverse events were reported, primarily consisting of diarrhea and headaches. The researchers noted limitations in the study, including the low enrollment of women and participants with rectal infections.
Zoliflodacin has received fast track designation from the Food and Drug Administration for the development of this oral treatment. A larger international clinical trial is anticipated to commence in the near future.
References
Taylor S.N. et al. Single-Dose Zoliflodacin (ETX0914) for Treatment of Urogenital Gonorrhea. The New England Journal of Medicine, 2018; 379:1835-1845. DOI: 10.1056/NEJMoa1706988.
Written by Man-tik Choy, Ph.D.