Shares of the Cambridge, Massachusetts-based company were up by more than 3.8% on Thursday after it announced Wednesday evening that it had enough data from its 30,000-person trial to begin its preliminary analysis. Moderna said it expects at least 53 people in the study have contracted the virus, the minimum number required for an independent data safety monitoring board to review and measure how well the vaccine works in those who received it.
"Moderna has seen a significant increase in the rate of case identification across sites in the last week," the company said in a press release Wednesday. About half of the participants have or will receive a placebo. Moderna said it doesn't know which patients received the vaccine or placebo.
Moderna told investors on Oct. 29 that it was "actively preparing" for the global launch of its potential vaccine after completing enrollment in its 30,000-person trial a week earlier. It said about 37% of the participants were from minority communities and 42% had other conditions or ages that put them at high risk of severe disease. Just over half, 53%, of the participants in the trial are male and 47% are female.
Investors anticipate Moderna's vaccine will be highly effective, especially after Pfizer, another frontrunner in the Covid-19 vaccine, said Monday that its vaccine was 90% effective, said Brad Loncar, a biotech investor and chief executive officer at Loncar Investments. Moderna's product, like Pfizer, is using messenger RNA, or mRNA, technology, a new approach to vaccines that uses genetic material to provoke an immune response.
Pfizer's vaccine news definitely bodes well for Moderna, Loncar said in a phone interview with CNBC.
Loncar said he doesn't expect Moderna's stock to tick lower if its effectiveness is a little less than Pfizer's, adding Moderna already has supply deals and the world will need multiple vaccines to slow the pandemic. "It'll still go up if the number is real close [to Pfizer's], he said. "But if it is significantly lower than that, then I do think it could be a problem."
The Food and Drug Administration had indicated it would approve a vaccine that's safe and at least 50% effective.
Pfizer, which is working with German drugmaker BioNTech, said Monday its analysis evaluated 94 confirmed Covid-19 infections among the trial's 43,538 participants. Pfizer said the case split between vaccinated individuals and those who received a placebo indicated a vaccine efficacy rate of above 90% at seven days after the second of the company's two-dose Covid-19 vaccine.
"We are reaching this critical milestone in our vaccine development program at a time when the world needs it most with infection rates setting new records, hospitals nearing over-capacity and economies struggling to reopen," Pfizer Chairman and CEO Dr. Albert Bourla said Monday.
It's unknown how many infections will be evaluated in Moderna's interim analysis. And while Moderna may announce the vaccine's overall effectiveness, the public will likely still have to wait for other key details, like how effective the vaccine is in the elderly or people with preexisting conditions, said Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia.
Pfizer's was "just a press release," Offit said. "You don't really know what the data are," he said, adding the public doesn't know exactly what level of disease was being prevented with Pfizer's vaccine and may not know until the vaccine has already been used on millions of people.
Safety data will also be crucial, he said. The FDA has said drugmakers need to provide at least two months of safety data after vaccinating volunteers before asking the agency to consider granting emergency use authorization.
Earlier this year, participants in Moderna and Pfizer's coronavirus vaccine trials told CNBC that they were experiencing high fever, body aches, bad headaches, daylong exhaustion and other symptoms after receiving the shots. But in interviews, all five participants — three in Moderna's study and two in Pfizer's trials — said they think the discomfort is worth it to protect themselves against the coronavirus.
Loncar also said he'll be watching out for any information on how well the vaccine generates T-cells, which scientists expect plays a role in long-term immunity against the virus. Data so far has suggested Pfizer's vaccine triggers a stronger T-cell response than Moderna's candidate, he said. "That's always made people a little nervous."