(Adds comment from Novavax executive)
By Dania Nadeem and Carl O’Donnell
March 11 (Reuters) – Novavax Inc’s COVID-19 vaccine was 96% effective in preventing cases caused by the original version of the coronavirus in a final stage test conducted in the United Kingdom, the company said on Thursday, taking a step forward for regulatory approval.
There was no case of serious illness or death among those who got the vaccine, the company said, in a sign that it could prevent the worst effects of the new variants that have emerged.
The vaccine was 86% effective in protecting against the most contagious virus variant first discovered and now prevalent in the UK, for a combined overall effectiveness rate of 90% based on infection data from both versions of the coronavirus.
Novavax’s shares jumped 22% on the floor to $ 229. They were trading below $ 10 on January 21, 2020, when the company announced it was developing a coronavirus vaccine.
In a smaller trial conducted in South Africa – where volunteers were mainly exposed to another more recent and more contagious variant that circulated widely and spread around the world – the Novavax vaccine was 55% effective, based on people without HIV, but still totally avoided serious illnesses.
Novavax medical director Filip Dubovsky said the performance in South Africa suggests that there may still be a case for using it in areas where the South African variant is dominant.
Novavax is also developing new formulations of its vaccine to protect against emerging variants and plans to start clinical trials of these vaccines in the second quarter of this year.
The results of the UK study’s final analysis were broadly in line with the interim data released in January.
The company hopes to use the data to submit for regulatory authorization in several countries. It is unclear when she will seek authorization from the United States or whether regulators will require her to complete an ongoing test in the United States.
Novavax expects test data from 30,000 people in the United States and Mexico by early April.
Dubovsky said Novavax is still planning to seek authorization from UK regulators in the beginning of the second quarter of 2021.
The UK trial, which involved more than 15,000 people between the ages of 18 and 84, assessed the vaccine’s effectiveness during a period with high transmission of the UK virus variant now in wide circulation.
The effectiveness of the injection in the South African trial decreased to around 49% when the analysis included data from HIV-positive participants.
The vaccine may be released for use in the United States as early as May, if US regulators decide that the UK data is sufficient to make a decision. It could take a few more months if they insist on seeing the test data in the United States for the first time, their chief executive told Reuters earlier this month.
“Ultimately, they have to decide whether the data we can present is adequate or whether they prefer to wait for the data from our study in the United States,” said Dubovsky on Thursday.
Novavax’s vaccine production plants are expected to be fully functional in April, executives said in a March investor call. The drugmaker hopes to have tens of millions of doses stored and ready for shipment to the United States when it receives authorization, CEO Stanley Erck told Reuters.
Novavax plans to produce its dual vaccine at eight manufacturing sites, including the Serum Institute of India.
If authorized, it would follow three COVID-19 vaccines previously approved for use in Britain by Pfizer and partner BioNTech, Moderna Inc and the AstraZeneca injection developed with the University of Oxford.
The Maryland-based company received $ 1.6 billion from the U.S. government to fund the vaccine test and guarantee 100 million doses.
(Reporting by Dania Nadeem in Bengaluru and Carl O’Donnell in New York; Editing by Bill Berkrot and Lisa Shumaker)