Most important differences for COVID vaccines will be efficacy and safety: Healthcare analyst
In early January, about the only thing the world’s scientists knew for sure about the novel coronavirus was its genetic profile. Now, some 300 days later, vaccine developers are on the brink of a major victory against a pathogen that’s inflicted untold personal and economic damage.
Virus specialists including Anthony Fauci, the top U.S. infectious disease doctor, predicted in early 2020 that it would take a year to 18 months to develop a vaccine to confront the contagion. Moderna Inc. and Pfizer Inc.’s collaboration with BioNTech SE are poised to beat that forecast if preliminary positive results from their vaccine trials hold up.
Pfizer CEO Albert Bourla said Tuesday that the company had reached a key safety-data milestone and would apply for U.S. emergency-use authorization. The news is fueling optimism for the quest to halt a disease that’s killed more than 1.3 million people and continues to run rampant.
“We are now accumulating the tools that will help us end the pandemic,” said Richard Hatchett, chief executive officer of the Coalition for Epidemic Preparednesss Innovations, which helped fund Moderna’s work. The auspicious results don’t mean that vaccines will be widely available immediately. “But, given where we are in this pandemic and where we are in the vaccine development process, you could not have asked for a better result.”
Bringing a conventional vaccine from inception to market takes more than a decade on average, and less than one in five that enters human trials gets to the finish line. A Merck & Co. mumps vaccine that was developed in 1967 has the record for speed: four years.
For COVID-19 vaccines, work began on Jan. 11, less than two weeks after initial cases were reported in China. That’s when researchers there published the genome of the coronavirus later known as SARS-CoV-2. That same Saturday, researchers at the U.S. National Institutes of Health began the first steps of laying out a vaccine program that became Operation Warp Speed, according to Health and Human Services Secretary Alex Azar.
Moderna, working with the NIH, and Pfizer-BioNTech used the genome sequence to design a molecule called messenger RNA. When injected into cells, the mRNA instructs them to make SARS-CoV-2’s spike protein, which the virus normally uses to invade cells. That key protein induces an immune response from the body.
Vaccines using mRNA have never been licensed for use in humans, but were pressed into service because of the speed with which they can be made. Researchers already had mRNA vaccine technology platforms, eliminating the need to create a new manufacturing process from scratch.
Messenger RNA vaccine production is especially rapid. It’s a chemical process that eliminates the need for growing proteins or viruses, a bottleneck that slows manufacturing of some other products. That meant human testing for Moderna’s vaccine began on March 16, about two months after research began. Pfizer’s and BioNTech’s vaccine entered tests soon after.
“It is absolutely unprecedented to have two vaccines with highly promising data from phase 3 trials less than a year after the global emergence of a novel pathogen,” HHS’s Azar said Monday on a call with reporters.
There are still many questions to be answered, including how long protection from the vaccines will last and how they’ll hold up under the scrutiny of regulators. They have to be manufactured and distributed to billions of people, in some cases under extreme conditions. Pfizer’s vaccine must be kept frozen at an ultralow –94 degrees Fahrenheit until a few days before it is used. Moderna’s doesn’t have the same storage requirements.
Other technologies, like the viral vector shot that AstraZeneca Plc is developing with the University of Oxford, have also proceeded rapidly, but still need to show they can work. The high initial efficacy rate seen with both the Pfizer and Moderna vaccines raises the odds that other shots targeting the spike protein will be successful.
“What these results have just done is raised the tide for all the boats in the harbor,” CEPI’s Hatchett said in an interview.
In the meantime, the central question -- can vaccines be designed and tested against a novel virus in a year -- is on the cusp of being answered in the affirmative. Other COVID vaccines have been developed and used in Russia and China, but before completing the rigorous testing that Pfizer’s and Moderna’s were subjected to. Russia now says its vaccine is 92 per cent effective based on an analysis of the first 16,000 volunteers in a large trial.
“We now know that immunization can lead to protection,” said Seth Berkley, head of Gavi, the Vaccine Alliance, on a call with reporters after the Pfizer efficacy data was released. The results also show that the focus on the spike protein was merited, he said.
A big part of what made the advance possible was money. U.S. taxpayers anted up as much as $18 billion for President Donald Trump’s Warp Speed program that funds development and manufacturing. And while Pfizer didn’t take funds for development, it benefited from giant supply contracts from the U.S. and other countries that guarantee a market if the vaccines are approved.
None of the funding would have had anywhere to go without the work of scientists who developed vaccine-making techniques over decades. In particular, Fauci pointed out, the government has been working with Moderna for years on developing the mRNA technology.
“I think that’s one of the things the general public doesn’t fully appreciate when they hear announcements like this,” he said on the Monday call. “They think this is something that just happened a few months ago; it did not.”
The U.S. Food and Drug Administration also took an encouraging approach, setting a minimum of 50 per cent effectiveness in reducing COVID cases for potential vaccine clearance. That helped drugmakers focus their big trials on meeting a clear-cut outcome.
The timing of the clinical trials turned out to be fortuitous. Both Pfizer’s and Moderna’s final-stage trials began July 27, in the middle of a COVID-constrained summer, and received widespread media attention.
By October, both trials had tens of thousands of participants and U.S. infections were skyrocketing. Since the studies’ success depended on accumulating a certain number of COVID-19 cases, the out-of-control epidemic -- as bad as it is for the country -- meant the trials were able to pile up cases and produce clear results quickly.
Faith in science was one of the reasons Yasir Batalvi, 24, volunteered for Moderna’s phase 3 trial. A political strategist for local campaigns in Massachusetts, Batalvi was discouraged by what he saw as misinformation around vaccines.
Batalvi rolled up his sleeve for a second dose -- not knowing whether it would be the vaccine or a placebo -- just last week. While he suffered side effects such as fatigue and injection pain, contributing to the process has been worth it, he said.
“The researchers just want the truth, and I trust the science,” he said.