IVI (International Vaccine Institute) announced that a new clinical study shows for the first time that an oral cholera vaccine (Shanchol) provides sustained protection against cholera, with protective efficacy of 65% over a five-year period in humans. The study, published in the Lancet Infectious Diseases, was a collaboration between scientists from the International Vaccine Institute (IVI) an international organization based in Seoul, and the National Institute of Cholera and Enteric Diseases, (NICED), an institute under the Indian Council of Medical Research (ICMR) of India’s Ministry of Health and Family Welfare. A Phase III clinical trial was jointly conducted by IVI and NICED in Kolkata, India in 2006 to assess the efficacy of the vaccine. More than 30,000 volunteers from one year old and up were enrolled in the study. A placebo group with a similar number of volunteers was also included.
Previous results from this study had shown that the vaccine provided 66% protection over a three-year period, and the new result shows that such protection is sustained for two additional years. Since vaccine protection does not wane over time, the study has important practical implications in terms of vaccination cost and vaccination strategies in developing countries.
Dr. Thomas F. Wierzba, Deputy Director General of Vaccine Development & Delivery at IVI and co-author of the study, said, “The study results suggest that this vaccine will protect persons at risk of severe cholera for five years. With protection sustained for five years, we will be able to provide greater benefits to the poor at reduced costs.” Dr. Christian Loucq, IVI’s Director General, commented, “The vaccine is safe, easy to administer, cost effective, and provides protection for up to five years. The use of the vaccine, combined with other control measures, will make it more feasible for developing countries afflicted by cholera to control a disease that plagues millions of people every year.”
[See also Journal Watch below: The Lancet Infectious Diseases]