Novavax (NVAX) plunges after its vaccine for a respiratory virus failed in a study

• The shares dropped 84 percent to $1.35 in late trading at 4:58 p.m. New York time.

 

Novavax announces topline RSV F vaccine data from two clinical trials in older adults, Resolve Phase 3 trial did not meet pre-specified efficacy objectives :

The co announced topline data from two clinical trials of its RSV F-protein recombinant nanoparticle vaccine candidate (RSV F Vaccine) in older adults. The Resolve trial, a Phase 3 trial of RSV F Vaccine in 11,856 older adults (60 years of age and older), did not meet the pre-specified primary or the secondary efficacy objectives, and did not demonstrate vaccine efficacy. Consistent with previous clinical experience, the vaccine was well tolerated.

• Phase 3 Resolve Trial:
  • "We are both surprised and disappointed by the outcome of the Resolve trial, which we recently unblinded. Our initial analyses and review of the key aspects of the trial do not indicate issues with trial execution, data collection, data integrity, or drug product quality. We expect to have preliminary immunogenicity data in the coming weeks to further our understanding of the trial results. Historically, annual seasonal RSV ARD attack rates between 3% and 7% have been observed in older adults. In our Phase 2 trial, we observed an RSV ARD attack rate of 4.9% and an RSV msLRTD attack rate of 1.8%. In contrast, we observed an RSV ARD attack rate of 2.0% and an msLRTD attack rate of 0.4% in our Phase 3 trial. These attack rates indicate a mild RSV season in older adults this year. We are continuing to investigate potential root causes that could have impacted the outcome of this trial. We continue to believe that there is a path forward for our RSV vaccine and that there is an important unmet need for an RSV vaccine in older adults."
• Phase 2 Rollover Trial:
• "The rollover trial demonstrated immunogenicity in all active vaccine recipients. As shown in the table above, there was a 6-fold increase in anti-F IgG in the Placebo-Vaccine arm, consistent with the Phase 2 efficacy trial. There was higher anti-F IgG at baseline in the Vaccine-Vaccine arm compared to the Placebo-Vaccine arm. Further, the Vaccine-Vaccine arm showed a greater than 2-fold increase in anti-F IgG from the higher baseline. We observed similar low attack rates and absence of efficacy of a single immunization in this trial as was observed in Phase 3 Resolve trial, although we did observe that a second season immunization could provide efficacy. The event rate comparisons made to either placebo groups suggested that the second season immunization was protective, even in a year with a very low attack rate. Further understanding of these data may come forth with full evaluation of the immune responses."

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