May 13, 2015
The National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health, has learned that NYVAC-HIV, an investigational HIV vaccine previously administered in two small HIV vaccine studies, was contaminated with a bacterium called Mycoplasma hyorhinis, which is known to cause disease in pigs but not in humans. The NYVAC-HIV was administered to 15 study participants in the HIV Vaccine Trials Network (HVTN) 092 clinical trial and 79 study participants in the HVTN 096 clinical trial. Vaccinations in both trials concluded in 2013, and no unusual adverse events have been reported since that time. However, out of an abundance of caution, study participants are currently being contacted and asked to return to their clinic sites for blood testing and physical examination.
The NYVAC-HIV vaccine was supplied by Eurovacc, a Switzerland-based not-for-profit organization. The investigational vaccine was manufactured for the two clinical trials by IDT Biologika, based in Germany. When the vaccine was produced in 2011, it passed approved sterility testing available at that time. The contamination was discovered when a new batch of the vaccine was created for a different study and was tested using a new, more sensitive DNA-based method. This prompted additional testing of the earlier vaccine lots using the newer DNA method, which revealed evidence of M. hyorhinis. It is currently unknown how the contamination occurred but investigations are underway.
The NIAID-sponsored HVTN 092 trial, which began in April 2013, was conducted by the NIAID-funded HVTN at eight sites in the United States and Switzerland and involved adults ages 18 to 50 years without HIV infection. It was a Phase 1 clinical trial designed to evaluate the safety and immune response of three injections with a DNA-based priming vaccine followed by a single boosting immunization with the NYVAC-HIV vaccine. Vaccinations in the trial were stopped in October 2013 after a study participant experienced a mild case of myocarditis, an inflammation of the heart muscle that ultimately resolved. FDA placed an official clinical hold on the trial in November 2013 because of the myocarditis event. NIAID, as the trial sponsor, notified the U.S. Food and Drug Administration of the vaccine contamination issue on May 1, 2015.
The Eurovacc-sponsored HVTN 096 clinical trial, which began in August 2012, was conducted at one site in Lausanne, Switzerland. The Phase 1 trial was evaluating the safety and tolerability of several investigational HIV vaccine regimens, including those using NYVAC-HIV as both a priming and boosting vaccine. Vaccinations in the trial ended in October 2013. Eurovacc has notified the Swiss regulatory authority in Europe of the vaccine contamination issue.
New vials of the NYVAC-HIV vaccine were made for evaluation in upcoming HIV vaccine research associated with the Pox-Protein Public-Private Partnership, or the P5-a diverse set of public and private organizations, including NIAID, focused on building on the success of the RV 144 HIV vaccine trial in Thailand. The new vials of NYVAC-HIV vaccine, which IDT produced in January 2015 for the P5 trials, have been rejected due to contamination with the mycoplasma. At this time, it is unclear what role, if any, the NYVAC-HIV vaccine will ultimately play in that research.