Clinical testing of an inactivated influenza A/H5N1 vaccine candidate in a double-blinded, placebo-controlled, randomized trial in healthy adults in Vietnam

Abstract

We tested an inactivated egg-grown whole virus influenza A/H5N1 vaccine candidate developed by the Institute of Vaccines and Medical Biologicals (IVAC), a state-run vaccine manufacturer in Vietnam, in a Phase 1, placebo controlled, double blinded, randomized trial. The vaccine was adjuvanted with aluminum hydroxide. The trial enrolled 75 subjects who were randomized to receive two injections of one of the following: low-dose of vaccine (7.5 mcg HA), high-dose of vaccine (15 mcg HA), or placebo. The vaccine candidate was well tolerated with minimal local reactogenicity consisting of mild, short-lived injection site pain and/or tenderness. No systemic reactogenicity was observed other than transient low-grade fever in about 13% of the subjects and no unsolicited adverse events were attributable to product administration. Immune responses were assessed at baseline and after the first and second dose by hemagglutination inhibition (HAI) and microneutralization (MN) assays, with 72% of the high-dose and 68% of the low-dose vaccine recipients presenting a ⩾4-fold response in the HAI assay and 72% of the high-dose and 61% of the low-dose vaccine recipients exhibiting a ⩾4-fold response in the MN assay. These promising results support further development. ClinicalTrials.gov number NCT02171819, June 20, 2014.

Randomized, double-blind, multi-center, phase III clinical trial to evaluate the immunogenicity and safety of MG1109 (egg-based pre-pandemic influenza A/H5N1 vaccine) in healthy adults

“…The rate of solicited AEs among MG1109 recipients was comparable to those from previous clinical trials of influenza vaccines, including both H5N1 monovalent and conventional trivalent influenza vaccines. [2][3][4][5][6] According to the meta-analysis of trials that assessed influenza H5N1 vaccine safety and immunogenicity, the rates of adverse events were reported variably: fever (0-8.7%), headache (8.3-46%), malaise (4-55%), myalgia (4-47%), local pain (14-89%) and erythema (0-42%). 7 In addition to the vaccine composition, the difference in the definition and severity threshold of adverse events might responsible for the wide range observed.…”

Knowledge and Perceptions of Influenza Vaccinations Among College Students in Vietnam and the United States

“…However, influenza prevention and treatment have been largely neglected across the health care system in Vietnam [ 9 ]. Previous studies on influenza in Vietnam have mainly focused on clinical testing of vaccines [ 10 ], the prevalence/epidemiology of influenza [ 11 ], or surveillance and control [ 12 ]. Little is known about perceptions, knowledge, and self-efficacy related to flu vaccinations in Vietnam.…”