A freeze-dried, temperature-stable, experimental tuberculosis (TB) vaccine candidate has entered a phase 1 human clinical trial, according to a news release from The National Institutes of Health. The vaccine candidate, ID93, was developed by scientists at the Infectious Disease Research Institute in Seattle, Washington, with support through a contract with the National Institute of Allergy and Infectious Diseases, a part of the National Institutes of Health. The trial is being conducted at the St. Louis University School of Medicine Center for Vaccine Development in Missouri.
ID93 is a recombinant powder formulation vaccine created from 4 proteins of Mycobacterium tuberculosis, combined with the adjuvant GLA-SE (an immunogenic protein). It is noted that freeze-dried powder vaccines are distributed to remote, resource-limited regions of the world at cheaper costs. As TB is a leading cause of infectious disease-related mortality worldwide, an efficacious and cost-effective vaccine is crucial to ending the epidemic. Presently, only the Bacillus Calmette-Guerin (BCG) vaccine is approved for TB prevention by the United States Food and Drug Administration; however, this vaccine has been inadequate in preventing TB in adolescents and adults.
The goal of ID93 treatment is to prevent reactivation or reinfection in people who have received the BCG vaccine or who have been exposed to TB. The trial will enroll approximately 48 healthy adult volunteers aged 18 to 55 years. Daniel Hoft, MD, PhD, principal investigator of the trial, reported that each participant will receive 2 vaccinations, 56 days apart. Half of the participants will receive the recombinant formulation of ID93; the other half will receive the previously tested 2-vial administration of the vaccine — powdered ID93 and liquid GLA-SE. Participants will be asked to provide blood samples at specified times during a period of 7 months and will be observed for any adverse reactions. Study investigators plan to examine the blood samples for generation of an immune response in participants.
Of note, the vaccine has recently demonstrated safety and immunogenicity in a phase 2a clinical trial in people in South Africa who had been cured of TB through standard therapy. The same results have been demonstrated in early clinical trials in the United States. Christopher Fox, PhD, vice president, Infectious Disease Research Institute and principal investigator of the National Institute of Allergy and Infectious Diseases contract, stated that “[the recombinant ID93] represents the first time a thermostable vaccine candidate containing a modern immune-boosting substance has reached clinical testing [and i]mplementing technologies designed for low-resource settings early in product development could help accelerate vaccine rollout in hard-to-reach areas.”
National Institutes of Health. Temperature-stable experimental tuberculosis vaccine enters clinical testing [news release]. https://www.nih.gov/news-events/news-releases/temperature-stable-experimental-tuberculosis-vaccine-enters-clinical-testing. January 23, 2019. Accessed January 23, 2019.