Novavax Announces Favorable Results From Phase 1/2a Pandemic Influenza Vaccine Program

Novavax, Inc. (Rockville, MD) has announced favorable results from the second stage of the Phase 1/2a human clinical trial of its pandemic influenza virus-like particle (VLP) vaccine candidate. The vaccine, which does not contain an adjuvant, induced robust neutralizing antibody responses. Novavax’s VLP candidate is directed against the H5N1 A/Indonesia/05/2005 avian influenza strain.

In this study, the vaccine demonstrated strong neutralizing antibody titers across all three doses tested, exhibiting increasing antibody titers with the escalation of the dose. The study evaluated individuals who received two injections of 15 micrograms (mcg), 45 mcg, 90 mcg, or placebo.

VLPs are recombinant structures mimicking the size and shape of the virus but lack genetic material and are therefore incapable of replication. Because they resemble actual infectious particles presenting proteins in the same conformation as on the wild-type virus, they are able to induce a potent immune response. The HA and NA are included to induce neutralizing antibody responses, whereas the M1 may induce cell-mediated immune responses that provide protection against drifted (i.e., mutated) strains.

Novavax’s manufacturing process makes it possible to potentially produce and distribute a vaccine matched to a pandemic strain in time to interrupt or halt a pandemic. Novavax’s influenza VLPs are produced in insect cell culture, using a manufacturing process that consists entirely of disposable, ready-to-use equipment. Current yields are 7–10 times higher than that of traditional egg-based or mammalian cell culture manufacturing. Because the Novavax process involves recombinant technology and does not require a live influenza virus, the vaccine can be manufactured within 10–12 weeks of identification of a pandemic strain, approximately 50% of the time duration required to manufacture egg-based vaccines.

These data are also supportive for moving forward with development of another Novavax vaccine candidate that is against seasonal influenza. Novavax has developed a vaccine candidate against seasonal (human) influenza strains. While current seasonal vaccines consist almost entirely of HA, the Novavax VLP contains HA, NA, and M1 with the potential of inducing neutralizing antibody to prevent infection and reduce the severity of influenza illnesses. Dose ranging studies in healthy young adults and adults 65 years of age and older are scheduled to begin later this year.

Novavax release (PDF)