A Safety and Immunogenicity Study of IVACFLU-A/H5N1

Avian Influenza Clinical Trial

Official title: A Phase 2/3 Double Blinded, Randomized, Placebo-controlled Study in Healthy Adult Volunteers in Vietnam to Examine the Safety and Immunogenicity of an Inactivated A/H5N1 Influenza Vaccine (IVACFLU-A/H5N1) Produced by IVAC

Status Completed

Clinical Trial Summary

The study hypothesis was that two 0.5 mL doses of whole virion monovalent A/H5N1 influenza vaccine (IVACFLU-A/H5N1) adjuvanted with alum would be safe and well tolerated in healthy adults, and that at least one of the two doses tested would be immunogenic in 60% or more of the subjects tested.

Clinical Trial Description

Although the A/H1N1 (2009) pandemic has subsided and the virus has become endemic, the threat of another pandemic due to avian influenza A/H5N1 remains constant. Since 1997, highly pathogenic A/H5N1 avian viruses have caused both widespread outbreaks in poultry with high mortality and sporadic, severe, and fatal disease in humans. Southeast Asian countries, including Vietnam, have been affected by influenza A/H5N1. From 2003 through March 2015, WHO has reported 826 confirmed human cases of A/H5N1 influenza infection; including 440 fatal cases (World Health Organization, 2015). Southeast Asian countries accounted for 42% of all confirmed influenza A/H5N1 cases reported since 2003, and influenza A/H5N1 infection in animals is now thought to be endemic in the region (World Health Organization, 2015). As of March 2015, Vietnam has reported 127 confirmed human cases and 64 deaths. In 2014, two cases of A/H5N1 avian influenza were reported in Vietnam. Therefore, the risk of transmission to human is still present.

At the time of the study, no influenza A/H5N1 vaccine had been licensed in Vietnam. IVACFLU-A/H5N1 is an influenza A/H5N1 vaccine produced by Institute of Vaccines and Medical Biologicals (IVAC) using embryonated chicken eggs. IVACFLU-A/H5N1 is a whole virus vaccine, collected in a linear sucrose density gradient solution using a continuous flow centrifuge (Alfa Wassermann, West Caldwell, NJ) and inactivated with formaldehyde. The vaccine is alum adjuvanted. Vaccine strain NIBRG-14 derived from original influenza A/Vietnam/1194/2004 was provided to IVAC by the National Institute for Biological Standards and Control of the Health Protection Agency of the United Kingdom. A clinical trial of IVACFLU-A/H5N1 vaccine conducted in 75 subjects at the Ben Luc Health District in Vietnam in 2014 showed that the vaccine is safe and immunogenic at doses of 7.5 and 15 mcg.

This study was conducted in two stages: Phase 2 was a dose selection study where subjects were randomized to one of the three groups (15 mcg IVACFLU-A/H5N1 vaccine, 30 mcg IVACFLU-A/H5N1 vaccine or placebo) at a 1:1:1 ratio. The conduct of Phase 3 was dependent on showing hemagglutination inhibition (HAI) response titer of ≥1:40 in ≥60% of vaccine recipients in at least one of the two Phase 2 IVACFLU-A/H5N1 vaccine groups. Based on the review of immunogenicity and safety results from the Phase 2 study, a dose of study vaccine was selected for Phase 3. Subjects were randomized at two sites (Khanh Hoa and Hai Phong) to receive the IVACFLU-A/H5N1 vaccine dose selected in Phase 2 or placebo . Safety was assessed in all subjects and immunogenicity was measured in a subset of subjects at the Hai Phong study site. ;

Related Conditions & MeSH terms

• Avian Influenza
• Influenza, Human

• NCT number: NCT02612909
• Study type: Interventional
• Source: Institute of Vaccines and Medical Biologicals, Vietnam
• Status: Completed
• Phase: Phase 2/Phase 3
• Start date: March 7, 2017
• Completion date: August 30, 2017