The Food and Drug Administration has approved a vaccine for the prevention of cholera caused by serogroup O1 in adults aged 18-64 years traveling to cholera-affected areas.
The vaccine, known as Vaxchora and manufactured by PaxVax, in Hamilton, Bermuda, is the only FDA-approved vaccinefor the prevention of cholera. According to the World Health Organization, serogroup O1 is the predominant cause of cholera globally.
“The approval of Vaxchora represents a significant addition to the cholera-prevention measures currently recommended by the Centers for Disease Control and Prevention for travelers to cholera-affected regions,” said Dr. Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research, in a statement.
According to the FDA announcement, Vaxchora is a live, weakened vaccine that is taken as a single, oral liquid dose of approximately 3 fluid ounces at least 10 days before travel to a cholera-affected area. The FDA stated that the effectiveness of Vaxchora has not been established in persons living in cholera-affected areas.
The FDA said the vaccine’s efficacy was demonstrated in a randomized, placebo-controlled human challenge study of 197 U.S. volunteers from aged 18-45 years. Of the 197 volunteers, 68 Vaxchora recipients and 66 placebo recipients were challenged by oral ingestion of Vibrio cholerae, the bacterium that causes cholera. Vaxchora’s efficacy was 90% among those challenged 10 days after vaccination and 80% among those challenged 3 months after vaccination.
CDC/ Janice Carr
A scanning electron micrograph of a number of Vibrio cholerae bacteria of the serogroup 01.
The Vaxchora application was granted fast track designation and priority review status by the FDA. The agency awarded PaxVax a tropical disease priority review voucher, which encourages the development of new drugs and biological products for the prevention and treatment of certain tropical diseases.
In addition to the primary human challenge study, PaxVax conducted two placebo-controlled studies to assess immune system response in the United States and Australia in adults aged 18-64 years. According to the FDA, in the group aged 18-45 years, 93% of Vaxchora recipients produced antibodies indicative of protection against cholera, while in the group aged 46-64 years, 90% produced antibodies indicative of protection against cholera.
The FDA revealed that the safety of Vaxchora was evaluated in adults aged 18-64 years in four randomized, placebo-controlled, multicenter clinical trials; 3,235 study participants received Vaxchora and 562 received a placebo. The most common adverse reactions reported by Vaxchora recipients were tiredness, headache, abdominal pain, nausea/vomiting, lack of appetite, and diarrhea.
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