Positive results from Stage A pivotal study of 2009 A/H1N1 VLP pandemic influenza vaccine

Novavax, Inc. (Nasdaq: NVAX) announced today positive results from the entire 1,000 subject Stage A of its two-stage pivotal study evaluating the safety and immunogenicity of Novavax's unadjuvanted 2009 A/H1N1 virus-like particle (VLP) pandemic influenza vaccine.  The data showed that safety and immunogenicity of the vaccine were consistent with preliminary results disclosed earlier from the first 500 volunteers of Stage A where the vaccine was found to be well tolerated and immunogenic at all three dose levels tested.  Novavax is conducting this study in collaboration with Avimex Laboratories of Mexico to support registration of the vaccine in Mexico and potentially other countries. The study is being conducted at the Mexican Institute of Social Security (IMSS), which is the largest medical and research center in Latin America.

The Stage A part of the pivotal trial is a randomized, double-blind, placebo-controlled study in which 1,000 healthy volunteers aged 18 to 64 years old were evaluated to determine the safety, tolerability and immunogenicity of the vaccine.  All volunteers were vaccinated with two doses of either 5 mcg, 15 mcg or 45 mcg of Novavax's 2009 A/H1N1 VLP pandemic influenza vaccine or a placebo. The DSMB reviewed the safety and immunogenicity data from 1,000 healthy volunteers.  Serological results from the 1,000 subjects 14 days after the first injection of Novavax's 2009 A/H1N1 VLP pandemic influenza vaccine showed that the vaccine at all three dose levels of 5 mcg, 15 mcg or 45 mcg induced robust immune responses that are considered protective.   The vaccine was well tolerated at all three dose levels and exhibited no systemic side effects and mostly mild local site reactions, similar to placebo.  These data confirmed that a single dose of 15 mcg was optimal to induce robust immune responses in broader age populations with a highly satisfactory safety profile.

"The success of Novavax's 2009 H1N1 VLP pandemic influenza vaccine in the Mexico pivotal study clearly demonstrates the desirable tolerability and immunogenicity profile of our vaccine candidate in the largest clinical trial conducted by the Company to date.   We are highly encouraged by these results as the data meet the immunogenicity criteria of both the United States and European regulatory authorities.  These data enable potential emergency use of the vaccine in pandemic situations and could be supportive in other countries in addition to Mexico.  Based on these positive data, we have filed for regulatory approval of our H1N1 VLP pandemic influenza vaccine candidate in Mexico," said Dr. Rahul Singhvi, President and Chief Executive Officer of Novavax.  "The substantial safety dataset and strong immunogenicity signal from this large study provide us confidence as we plan Phase III studies of our seasonal trivalent influenza VLP vaccine, pending results from the ongoing Phase IIa trial in older volunteers and discussions with the U.S. Food and Drug Administration (FDA)."

Earlier this month, Novavax completed enrollment of a cohort of over 3,500 volunteers in Stage B of this pivotal study.  Over 2,500 of these volunteers received a single 15 mcg injection of Novavax's unadjuvanted 2009 A/H1N1 VLP pandemic influenza vaccine while 1,000 of the volunteers received a placebo.  The purpose of Stage B portion of this clinical study was to evaluate safety of the VLP vaccine.