Moderna, one of the developers in the lead for a vaccine to prevent Covid-19, is slowing enrollment slightly in its large clinical trial to ensure it has sufficient representation of minorities most at risk for the disease, its chief executive said.
The trial is designed to enroll 30,000 people in the U.S. to prove the vaccine's safety and efficacy. As of Aug. 28, it had enrolled 17,458, 24% of whom are from communities of color. The company provides updates on enrollment numbers every Friday afternoon.
Moderna shares, which have a market value of $23.5 billion, were down more than 8% after the news, and had recovered somewhat by early afternoon. The stock has risen 211% since the start of the year.
Enrolling the elderly, communities of color and people with underlying health conditions is a priority for the coronavirus vaccine trials, given they're at greater risk from the disease. Public health experts note inclusion of diverse groups is important for ensuring the vaccines work in every population, and for building trust among all communities to take the vaccine if and when it becomes available.
"The Black community has been disproportionately impacted by the pandemic, and that's not biological but rather due to socioeconomic inequities resulting from racism," said Angela Rasmussen, a virologist at Columbia's Mailman School of Public Health. "It is particularly important to make sure that Black and Latinx participants are represented equitably in the trials and the vaccine shows protective efficacy in different populations of people."
Moderna's data show that two-thirds of those enrolled in the study are White, 20% are Hispanic or Latino and 7% are Black.
"We believe we could have one of the best vaccines," Moderna CEO Stephane Bancel told CNBC. "We want to ensure we have data for all the people who could benefit and be protected."
Bancel said the company's goal is for enrollment to line up with U.S. Census Bureau numbers. In 2019, the Census Bureau estimated 18.5% of people in the U.S. are Hispanic or Latino, and 13.4% are Black or African-American alone.
Moderna started its trial on July 27, the same day as pharmaceutical giant Pfizer. Pfizer's CEO said Thursday the company had enrolled 23,000 people of its planned 30,000, ahead of schedule, and that data showing whether the vaccine works could be available as soon as the end of October.
As of Monday, 25% of U.S. participants in Pfizer's trial were Asian, Black, Hispanic/LatinX or Native American, the company said. Eight percent were Black.
And though the enrollment numbers for minorities lag where experts hoped they'd be, they're still ahead of a national registry for those expressing interest in Covid-19 vaccine trials. NBC News reported this week the registry for the Coronavirus Prevention Network, a group formed by the National Institute of Allergy and Infectious Diseases to conduct vaccine and antibody therapy trials, included only 40,000 people from minority groups of 360,000 people total who expressed interest in trials — about 11%.
White House advisors cast doubt on Pfizer's projection that data could be available as soon as the end of next month. NIAID Director Dr. Anthony Fauci told CNN it's "unlikely but not impossible," and that most experts are anticipating November or December for trial data. Moncef Slaoui, lead advisor to the government's Operation Warp Speed, told NPR there's a "very very low chance that the trials... could read [out] before the end of October."
Pfizer is part of Operation Warp Speed, but didn't accept government funding — or participation — for the development and trials of its vaccine, which is partnered with German developer BioNTech. It gets paid $1.95 billion for 100 million doses only if the vaccine is successful.
Moderna partnered with Fauci's NIAID early on in the pandemic to develop its vaccine candidate, and has received almost $1 billion in government funding for development, in addition to a purchase order for $1.53 billion for 100 million doses.
Bancel didn't provide a new projection for when the study might be fully enrolled or show data. When the trial began, he had told CNBC in an interview that data could be available in October in "a really optimistic scenario; maybe November."
Friday he noted "a small delay to have a better quality trial is the right decision in the long run," saying the company has told several clinical trial sites "they need to do better" in reaching minorities.
"I would rather we have higher diverse participants and take one extra week," Bancel said. Diversity "matters more to us than speed."
Dr. Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia, said he was glad to hear Moderna was ensuring diversity in its trial even if it caused a slight delay.
"It is important for when you roll this vaccine out, because people are skittish, groups like the African-American/Black community need to know they've been represented in the trials, and the vaccine has been found to be safe and effective for them," Offit said in an interview.
The vaccine needs to be proven to work in "those greater than 65, minority groups, those with certain medical conditions like obesity, because those are the people who are going to get it first," he said.