Novavax has revealed final efficacy analysis of its COVID-19 vaccine NVX-CoV2373, after reporting interim results from the UK-based phase 3 trial in January.
The final analysis from the trial, which enrolled 15,000 participants, demonstrated a 96.4% vaccine efficacy mild, moderate and severe disease caused by the original COVID-19 strain.
Against the B.1.1.7 strain, first identified in the UK, NVX-CoV2373 was found to be 86.3%, reflecting an overall vaccine efficacy of 89.7%.
In participants aged 65 years and older, ten cases of COVID-19 were observed, with 90% of these cases occurring in the placebo group.
Novavax also announced data from a phase 2b trial of NVX-CoV2373 conducted in South Africa – one cohort evaluated the efficacy and safety of the vaccine in approximately 2,665 healthy adults, while a second cohort evaluated the vaccine in around 240 medically stable, HIV-positive volunteers.
Analysis of vaccine efficacy among 147 PCR-positive COVID-19 cases demonstrated an overall efficacy of 48.6% against ‘predominantly variant strains’.
According to Novavax, most of the cases circulating during the efficacy analysis were caused by the B.1.351 variant circulating in South Africa.
Among HIV-negative participants, the efficacy of NVX-CoV2373 was found to be 55.4%, with complete analysis showing that vaccine-induced protection began 14 days after the first dose.
Novavax added that increased efficacy was observed seven days after the second dose.
“We are very encouraged by the data showing that NVX-CoV2373 not only provided complete protection against the most severe forms of disease, but also dramatically reduced mild and moderate disease across both trials. Importantly, both studies confirmed efficacy against the variant strains,” said Stanley Erck, president and chief executive officer, Novavax.
“Today [11 March] marks one year since the WHO officially declared the COVID-19 pandemic, and with this data in hand, we are even more motivated to advance our vaccine as a potential weapon in the fight to end the suffering caused by COVID-19,” he added.
The company added that it expects the final UK phase 3 data to serve as the basis for submissions for authorisation with ‘various regulatory agencies’ across the globe.