Covid-19 vaccine Photograph:( Reuters )
Despite setbacks, drugmakers and research centres around the world continue to work on COVID-19 vaccines, with large global trials of several of the candidates involving tens of thousands of participants well underway.
The entire world is scrambling to formulate a potion for the coronavirus-ravaged human race -- a Covid-19 vaccine. And scientists have been successful too.
But the vaccines have unfortunately exhibited a few side-effects -- proving to be a setback for humanity and its survival in the face of the raging coronavirus pandemic.
Drugmakers and research centres around the world, however, continue to work on COVID-19 vaccines, with large global trials of several of the candidates involving tens of thousands of participants well underway.
Here's a status check of the global race to deliver vaccines to help end the coronavirus pandemic:
PFIZER INC
US drugmaker Pfizer Inc has become the first company to release preliminary data showing that their shot worked in late-stage clinical trials.
In a major victory in the war against a virus that has killed over a million people and battered the world's economy, Pfizer Inc said its experimental COVID-19 vaccine is more than 90% effective based on initial trial results.
The interim analysis, conducted after 94 participants in the trial developed COVID-19, examined how many had received the vaccine versus a placebo. Pfizer did not provide that detail, but over 90% effective implies that no more than 8 of the 94 had received the vaccine, administered in two shots about three weeks apart.
The efficacy rate, which could drop once full results are available, is well above the 50% effectiveness required by the US Food and Drug Administration for a coronavirus vaccine.
But this appeared a contentious as one of the volunteers of the trial, Texas lobbyist Glenn Deshields compared side effects of the shot as being similar to "a severe hangover" whereas another one, 45-year old Carrie said that she went through fever, body aches and headache after the second shot.
Pfizer and German partner BioNTech, however, said they had found no serious safety concerns yet and expected to seek US emergency use authorisation this month, raising the chance of a regulatory decision as soon as December.
Shortly after Pfizer’s announcement, Russia said its Sputnik V vaccine was also more than 90% effective, based on data collated from inoculations of the public.
RUSSIA'S SPUTNIK V
Russia’s Sputnik V vaccine was found to be 92 per cent effective at protecting people from COVID-19 according to interim trial results, the country’s sovereign wealth fund said on November 11.
But this came at a cost.
Russia registered the vaccine for public use in August, the first country to do so, ahead of the start of the large-scale trial in September.
But soon after, Russian health minister Mikhail Murashko said that one in seven volunteers complained of side effects, including weakness and muscle pain after receiving the Sputnik V coronavirus vaccine.
Results of the phase 1/2 trials of the vaccine published in The Lancet showed no serious adverse effects and a stable immune response in 100 per cent of participants.
Despite this, Russian health authorities announced advanced trials of Sputnik V among 40,000 volunteers two weeks after it received government approval. Officials also said that vaccination of risk groups, such as doctors and teachers, will be carried out in parallel to the studies.
More than 55,000 volunteers had applied to take part in post-registration clinical trials of the Sputnik V vaccine -- the results of which were announced two days back.
Post-registration trials of Russia’s Sputnik V coronavirus vaccine revealed no new side effects, Director of the Gamaleya Scientific Research Institute of Epidemiology and Microbiology Alexander Gintsburg told the Rossiya-24 TV channel.
"These expanded trials have proved that about 15-17% of those vaccinated develop side effects, which means that 80% don’t have any issues after vaccination," Gintsburg added.
According to him, potential side effects include a small temperature rise for up to two days, redness at the injection site, headache and muscle discomfort.
According to the Russian Health Ministry, experience shows that such vaccines are capable of creating long-term immunity that lasts for up to two years.
ASTRAZENECA
AstraZeneca got the FDA’s all-clear to restart the US study of its COVID-19 vaccine almost three weeks back.
Although the agency couldn’t rule out a link between AstraZeneca’s vaccine and side effects observed in one patient, it did not find the vaccine was responsible for them.
At least two participants in AstraZeneca’s phase III trial had experienced transverse myelitis, an inflammatory syndrome that affects the spinal cord.
On September 11, AstraZeneca published a report saying “there was insufficient evidence to say for certain that the illnesses were or were not related to the vaccine.”
The British pharma company halted testing globally last month after the first case of transverse myelitis was reported.
The company has now resumed phase 3 trials in the UK, Brazil, South Africa and India, but not yet in the US.
AstraZeneca had also employed a blood-cancer medicine Calquence to help patients hospitalised with respiratory symptoms of Covid-19. But the group of patients taking the drug in addition to standard care didn’t show fewer deaths or respiratory failures, the drugmaker said in a statement.
Meanwhile, Serum Institute of India, the world's largest vaccine producer, has said it has made 40 million doses of AstraZeneca's potential Covid-19 vaccine, and will soon begin making Novavax's rival shot, as they both seek regulatory approval.
JOHNSON & JOHNSON
Then came Johnson & Johnson -- which paused its phase III vaccine trial after a volunteer experienced unexplained illness after receiving the shot.
The company didn’t disclose what the illness was. It’s also unclear whether the sick participant was in the actual vaccine group or in the placebo group.
"Adverse events—illnesses, accidents, etc.—even those that are serious, are an expected part of any clinical study, especially large studies," Johnson & Johnson said in a statement.
CHINA'S SINOVAC
Brazil's health regulator halted clinical trials of the potential coronavirus vaccine CoronaVac, citing an “adverse, serious event.”
The decision posted on Anvisa's website this month elicited immediate surprise from parties involved in producing the vaccine.
The potential vaccine is being developed by Chinese biopharmaceutical firm Sinovac and in Brazil would be mostly produced by Sao Paulo's state-run Butantan Institute.
On November 12, Anvisa allowed the resumption of late-stage Brazilian clinical trials for Sinovac vaccine.
It was reported there had been no need to stop the study as the death had no relation to the vaccine.
Brazil has one of the world’s worst COVID-19 outbreaks, with more than 5.7 million confirmed cases and 163,000 deaths. And President Jair Bolsonaro has come under fire for his constant dismissal of the virus and its dangers.
(with inputs)