Two companies reveal how they are evaulating vaccines.
Documents show timing of approval is far from certain
WASHINGTON
Two drug companies that are leading the race to develop coronavirus vaccines bowed to public pressure Thursday, abandoning their traditional secrecy and releasing comprehensive road maps of how they are evaluating their vaccines.
The companies, Moderna and Pfizer, revealed details about how participants are being selected and monitored, the conditions under which the trials could be stopped early if there were problems, and the evidence researchers will use to determine whether people who got the vaccines were protected from COVID-19.
Moderna’s study will involve 30,000 participants, and Pfizer’s 44,000.
Companies typically share these documents after their studies are complete. The disclosures while the trials are still underway, a rare move, are aimed at addressing growing suspicion among Americans that President Donald
Trump’s drive to produce a vaccine before the election on Nov. 3 could result in a product that was unsafe.
The plan released by Moderna on Thursday included a likely timetable that could reach into next year for determining whether its vaccine works. It does not jibe with the president’s optimistic predictions of a vaccine widely available to the public in October.
Pfizer’s plan does not appear to estimate when its results could be available. Its chief executive has said repeatedly that the company hopes to have an answer as early as October. Moderna has said only that it could have a result before the end of the year.
Moderna’s 135-page plan, or protocol, indicated that the company’s first analysis of early trial data might not be conducted until late December, though company officials now say they expect the initial analysis in November. In any case, there may not be enough information then to determine whether the vaccine works, and the final analysis might not take place until months later, heading into the spring of next year.
Moderna’s timeline meshes with the cautionary estimates from many researchers, including Dr. Robert Redfield, the director of the Centers for Disease Control and Prevention, who told senators Wednesday that a vaccine would not be widely available until the middle of next year. Hours later, Trump sharply contradicted him, making unsubstantiated projections that a vaccine could become widely available weeks from now.
On Wednesday, Joe Biden, the Democratic presidential nominee, said in Wilmington, Del., that the process used to evaluate and approve a vaccine would have to be “totally transparent” to win public confidence. He has said that Trump’s calls for companies and regulators to speed the process have shaken the public’s faith in vaccines and that politics has no place in vaccine development.
Researchers in particular have been urging vaccine makers to share the detailed blueprints of their studies so that outside experts can evaluate them. At least one expert, after reading the plans, has already raised questions about the way the trials were designed.
Until now, none of the nine companies that are testing vaccines in large clinical trials had released this level of detail.
Moderna, Astrazeneca and Pfizer, which is collaborating with German company Biontech, are among the front-runners in the global race to produce a vaccine to fight the pandemic.
Astrazeneca did not respond to inquiries about whether it would now disclose its study plan. Novavax, which is expected to start a large, advanced clinical trial later this year, also did not comment. Johnson & Johnson, which has said it plans to begin a large trial this month, said it would have “more information to share” when the trial starts.
Astrazeneca’s trial was stopped temporarily because of serious illness in a participant. It has resumed in Britain and Brazil, but not in the United States.
Earlier studies of both vaccines in small numbers of people found that after the second shot, they developed socalled neutralizing antibodies, which can inactivate the virus in lab tests. The vaccines also produced a favorable response involving T-cells, another part of the immune system.
Dr. Eric Topol, a clinical trial expert at Scripps Research
in San Diego, gave Moderna “big kudos” for sharing its plan but said that he was disappointed that Moderna intended to include in its data people who had developed relatively mild cases of COVID-19. He said more compelling evidence of the vaccine’s effectiveness would be produced if the company counted only moderate to severe cases.
Moderna’s plan also allows for the possibility of stopping the trial early after a relatively small number of cases, potentially leading to an exaggerated perception of the vaccine’s efficacy and missing safety problems that could turn out to be significant later if the vaccine were given to millions of people, he said.
Topol was more critical of Pfizer’s plan because it allowed even milder cases than Moderna’s to be counted and provided more opportunities to stop the trial early based on few cases, which he called troubling
“Take the time, the extra weeks,” Topol said. “No shortcuts. Nobody will regret it. I’ve been doing clinical trials for decades. I don’t know if there’s ever been a more important one than this one. I’d like to see it done right, and not stopped early.”