A clinical trial testing a freeze-dried, temperature-stable experimental tuberculosis (TB) vaccine in healthy adults found that it was safe and stimulated both antibodies and responses from the cellular arm of the immune system. The Phase 1 trial was supported by the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health. A non-temperature stable form of the candidate previously had been tested in several clinical trials. However, this was the first clinical trial of any subunit TB vaccine candidate in a temperature-stable (thermostable) form. Results are published in Nature Communications.
The experimental vaccine, ID93+GLA-SE, was developed by Christopher B. Fox, Ph.D., and scientists at the Access to Advanced Health Institute (formerly the Infectious Disease Research Institute) in Seattle. It is a recombinant subunit vaccine made from four proteins of Mycobacterium tuberculosis bacteria combined with GLA-SE, an immune-stimulating adjuvant. The freeze-dried formulation does not require refrigeration and is mixed with sterile water just prior to injection. Thermostable vaccines are desirable in settings where maintaining cold or frozen vaccines for long periods can be costly and difficult.
The current trial investigated whether administering temperature-stable vaccine containing both ID93 and GLA-SE in a single vial would be as effective at inducing an immune response as a regimen in which non-thermostable ID93 and liquid GLA-SE are held in two vials and combined prior to injection. A single-vial presentation of a thermostable vaccine would have clear advantages in ease of storage, transport and administration, the investigators note.
Daniel F. Hoft, M.D., Ph.D., director of the Saint Louis University Center for Vaccine Development, led the single-site trial at the university’s School of Medicine. Twenty-three participants received the thermostable single-vial regimen, while 22 participants received the two-vial, non-thermostable regimen. Both vaccine presentations were safe and well-tolerated. Recipients of the single-vialled thermostable vaccine had robust T-cell responses and produced higher levels of antibodies in the blood than those receiving the non-thermostable two-vial presentation.
The investigators note some limitations in this small trial. For example, no established correlates of protection define what immune responses are required for vaccine-induced protection from TB disease. Therefore, it is not possible to say whether the enhanced immune responses seen in the thermostable vaccine formulation would translate to improved protective vaccine efficacy. Nevertheless, they conclude, results of this trial demonstrate “a proof-of-concept that adjuvant-containing vaccines can be formulated in a freeze-dried single-vial presentation without detrimentally impacting clinical immunogenicity or safety characteristics.”
ZK Sagawa et al. Safety and immunogenicity of a thermostable formulation of the ID93 + GLA-SE tuberculosis vaccine candidate in healthy adults. Nature Communications DOI: 10.1038/s41467-023-36789-2 (2023).
Lakshmi Ramachandra, Ph.D., program officer, Tuberculosis and Other Mycobacterial Diseases Section, Division of Microbiology and Infectious Diseases, NIAID, is available to discuss this trial.
To schedule interviews, please contact Anne A. Oplinger, (301) 402-1663, niaidnews@niaid.nih.gov(link sends e-mail).
This research was funded under NIAID contract HHSN272201400041C. Additional information about the trial is available on clinicaltrials.gov using the identifier NCT03722472.
NIAID conducts and supports research—at NIH, throughout the United States, and worldwide—to study the causes of infectious and immune-mediated diseases, and to develop better means of preventing, diagnosing and treating these illnesses. News releases, fact sheets and other NIAID-related materials are available on the NIAID website.
About the National Institutes of Health (NIH): NIH, the nation's medical research agency, includes 27 Institutes and Centers and is a component of the U.S. Department of Health and Human Services. NIH is the primary federal agency conducting and supporting basic, clinical, and translational medical research, and is investigating the causes, treatments, and cures for both common and rare diseases. For more information about NIH and its programs, visit www.nih.gov.
NIH…Turning Discovery Into Health®
Source: National Institutes of Health