BioNTech and Pfizer’s Covid-19 vaccine has proved 90% effective in phase III interim results. This has led to stock price rises upwards of 10% for biotechs developing vaccines based on mRNA technology.
The ongoing phase III trial — run by the German firm BioNTech and its big pharma partner Pfizer– has recruited over 43,000 volunteers. Almost 39,000 of these have already received the full regime of two doses around three weeks apart. The aim is to gauge the effectiveness of their Covid-19 vaccine, which is made out of messenger RNA (mRNA).
According to interim results, there were 90% fewer confirmed Covid-19 cases in the group of volunteers that received two doses of the vaccine compared to the group that received a placebo. Furthermore, no serious safety concerns were seen.
This interim analysis was made once 94 confirmed cases of Covid-19 had been detected in the study population. This is because they agreed with the FDA that a threshold of 62 cases was needed before the interim analysis would be considered by the regulatory agency.
BioNTech and Pfizer plan to wait for safety data from volunteers around two months after their second injection, which the companies expect later this month. With this data in hand, they then aim to apply for an Emergency Use Authorization from the FDA, which allows the vaccine to be used before getting full approval during the pandemic. The topline results for the trial will be released after there are a total of 164 confirmed Covid-19 cases in the trial population.
“Especially today, while we are all in the midst of a second wave and many of us in lockdown, we appreciate even more how important this milestone is on our path towards ending this pandemic and for all of us to regain a sense of normality,” said Ugur Sahin, BioNTech’s co-founder and CEO.
BioNTech and Pfizer’s candidate is one of the frontrunners in the race to develop a vaccine for Covid-19. Its closest phase III competitors include vaccines from giants such as AstraZeneca, the Chinese company CanSino Biologics, and the US mRNA company Moderna. While there are two vaccines in Russia with regulatory approval, they lack phase III results so far.
As a result of the big news, BioNTech’s stock price has jumped by almost 20% overnight. There were also stock price surges of more than 10% for other public companies developing Covid-19 vaccines based on mRNA. These include Moderna and the German CureVac, which is soon entering phase IIb testing.
“Having multiple Covid-19 vaccines would be a good thing, as some vaccines may work better for certain populations,” said Chris Cardon, CEO of the Belgian firm Ziphius Therapeutics, which is developing its own mRNA vaccine for Covid-19.
The pandemic has provided tremendous publicity to companies making vaccines made from mRNA, which has in many cases translated into huge windfalls. For example, CureVac has reaped huge rewards in the form of grants, private investments, and a €180M Nasdaq IPO.
While no mRNA vaccines have ever been approved, they are attractive to investors because they could be easier, cheaper, and faster to develop and manufacture than traditional vaccines. This could be essential for combating global pandemics going forward, as well as for producing therapies for many other indications such as oncology.
“Despite the accelerated development and clinical testing of the Covid vaccines, this is a special case scenario, and other indications may not be able to progress so rapidly in future,” observed Michael Mulqueen, VP Business Development at the Belgian mRNA company eTheRNA. “Nevertheless, this is an approach that is likely to provide a wave of new therapies in the near future, akin to the antibody revolution in medicine seen in the 1990s.”
One limitation of BioNTech’s mRNA vaccine candidate is that it needs to be stored at around -70 degrees centigrade. This means it could be hard to distribute to places that lack specialized equipment. BioNTech’s competitor CureVac expects its candidate to be stable at fridge temperatures and therefore could overcome the storage issue, according to its Vice President of Communications, Thorsten Schüller.
While BioNTech and Pfizer’s results are very encouraging for vaccine efforts against Covid-19, the companies haven’t yet released the full data. This leaves many questions still unanswered, such as which age groups have been analyzed, how ill were the volunteers that got Covid-19, how long the protection can last, and whether it prevents Covid-19 cases without symptoms.
“Protection against infection as well as against illness would reduce the severity of an outbreak within the community and enable more effective control of the disease, enabling communities to return to something more like normal life,” noted Penny Ward, Visiting Professor in Pharmaceutical Medicine at King’s College London, in a public statement.
A concern of Stephen Evans, Professor at London School of Hygiene & Tropical Medicine, is that the companies have revealed these interim results before enrolling all the volunteers.
“The ethics of continuing to randomize people to placebo within this trial may be questioned. It may also lead to pressure to vaccinate the placebo group with the Pfizer vaccine,” Evans told the UK’s Science Media Centre. “This will mean that the longer-term follow-up within the properly randomized trial will become difficult, and it may be the longer term where the true benefit and harm balance will need to be assessed.”
A further question remains over whether the virus responsible for Covid-19, SARS-CoV-2, could evolve beyond the reach of the first generation of Covid-19 vaccines. Most vaccines in development exclusively target a protein called spike, which the virus uses to infect cells. So far, the spike protein has mutated little, with one scare arising this month when one such mutation was found in minks. A small group of companies including eTheRNA are developing Covid-19 vaccines designed to hit different parts of the virus, with less room for escape via evolution.
Finally, even once an effective Covid-19 vaccine makes it to market, producing it in sufficient quantities to protect the population against Covid-19 will be a huge challenge.
“Assuming the vaccine is approved, the immediately available supplies are likely to be used to protect key workers, including emergency response personnel, and the vaccine may not be generally available to the whole population until late 2021 or later,” said Mulqueen. “So, the current social distancing measures will need to continue at least through the current season and likely well into next year.”
Image from Elena Resko and Shutterstock