Merck & Co/MSD has become the first company to file for approval of an Ebola vaccine in the US, and is due to get a verdict from the FDA in March after being granted a priority review.
The V920 or vRVS-ZEBOV vaccine – which is designed to protect against the Ebola Zaire strain and was licensed from NewLink Genetics – was granted breakthrough status by the US regulator in July 2016.
It has already been approved for use in emergencies by the World Health Organization (WHO), based on trials conducted during the 2014-2016 Ebola epidemic in West Africa which suggested it had 93% protective efficacy.
It is also under regulatory review in Europe, and Merck has filed for prequalificated medicine status which would clear the way for more widespread use by international procurement agencies.
“A top priority for us remains achieving registration of V920 and regulatory approval of our German manufacturing site, so that licensed supply can be produced over time to support global public health preparedness and health security objectives,” said Paula Annunziato, vice president, Merck Research Laboratories.
The filing comes as the ongoing outbreak of Ebola Zaire in the Democratic Republic of the Congo – now more than a year old – saw the number of cases head to around 3,000 as of the end of August, making it the second-largest epidemic of the virus ever. There was an average of around 80 new cases every week over the summer, according to WHO).
The death toll – with nearly 2,000 deaths among those recorded cases – is a stark reminder of just how virulent and deadly the Ebola virus can be.
Merck may only be filing for approval of V920 now, but it has already been making the vaccine available to areas at risk of Ebola outbreaks, including the DRC.
More than 200,000 people have been vaccinated against Ebola in the country, either with V920 or another experimental vaccine from Johnson & Johnson.
The vaccines have been given in a ring vaccination strategy, with vaccination radiating out from those in contact with diagnosed cases of the infection in order to try and contain its spread in the absence of mass immunisation.
Earlier this year the WHO declared the DRC outbreak a public health emergency of international concern (PHEIC) after Ebola reached the major transport hub of Goma, on the border with Rwanda, which in turn prompted calls for a mass vaccination campaign.
Merck is out in front when it comes to getting formal approval for an Ebola vaccine, as J&J’s Ad26.ZEBOV and another candidate called MVA-BN-Filo from Bavarian Nordic are still in clinical testing in Uganda.
GlaxoSmithKline also had three Ebola vaccine candidates in development but out-licensed them to the US Sabin Vaccine Institute for free last month.