- Moderna on Monday disclosed early results from a Phase 1 study of its experimental coronavirus vaccine, marking a milestone in the global pursuit of a protective treatment for a virus that's infected more than 4 million people.
- The vaccine was generally safe, the results showed, and the first eight volunteers who received low or medium doses have produced what appear to be meaningful levels of antibodies that can neutralize the coronavirus in test tubes. Moderna will move forward with doses within that range; the highest-tested dose led to three serious "systemic symptoms," the Cambridge, Massachusetts-based biotech said.
- Moderna plans to begin a Phase 3 trial of its vaccine, dubbed mRNA-1273, in July — a timeline without precedent in vaccine development. But that speed will likely mean less is known about any resulting candidate if and when it's pressed into emergency use.
Since early this year, Moderna has been at the forefront of an urgent worldwide push to develop a vaccine for the coronavirus in just months, rather than the many years vaccines typically take to test. On Monday, the biotech became the first company to report data from a study of human volunteers.
The results — an early look at a 45-volunteer Phase 1 trial sponsored by the National Institutes of Health — aren't nearly enough to prove whether the vaccine is safe or can prevent infection with SARS-CoV-2.
Much more data from larger and longer studies will be needed to more definitively prove whether mRNA-1273 can protect against infection by the new coronavirus. Instead, this first look is meant to show which doses appear promising enough to move into wider testing, that the vaccine doesn't cause any serious health programs and that it can spur the body to produce antibodies capable of neutralizing the virus.
While only summary data are available, Moderna looks to have accomplished those early goals.
In the trial, three small groups of healthy people between 18 and 55 years old received one or two shots of mRNA-1273 at three dose levels: 25, 100 or 250 micrograms.
The company reported that the immune responses observed were higher with each dose — a sought-after pattern that suggests benefits are positively correlated with dose level. Two weeks after getting their second shot, at day 43, 15 people on the low dose had levels of binding antibodies comparable to what is seen in blood samples of patients who have recovered from COVID-19.
In the 10 people given the medium dose, the levels of those antibodies "significantly exceeded" the numbers seen in recovered patients. Samples aren't available yet for the remaining study volunteers, including those who got the highest dose.
Thus far, data on neutralizing antibodies — the proteins used by the immune system to fight off infections — are only available for the first four volunteers to get the low or medium doses. After 43 days, all eight of them produced antibodies that were capable of neutralizing live SARS-CoV-2 in a serological test known as a PRNT assay.
Supporting that finding were data from a preclinical test in mice infected with the virus, which showed inoculation with mRNA-1273 prevented viral reproduction in the animals' lungs, Moderna said.
"The totality of the data released today, the interim Phase 1 data and the preclinical mouse challenge model, give us confidence that mRNA-1273 has a high probability to provide protection from COVID-19 disease in humans," said CEO Stéphane Bancel on a Monday conference call.
One volunteer in the low and medium dose groups had a side effect deemed severe, redness around the site of injection. There were more worrisome findings at the high dose: three cases of severe "systemic symptoms" after the second shot.
"I believe these flu-like symptoms are really an indirect measure of a strong immune response," said Tal Zaks, Moderna's chief medical officer, on the conference call. All observed side effects "have been transient and self-resolving," he added.
Based on the findings, Moderna will drop its high dose and test a 50 microgram and 100 microgram dose in the planned Phase 2 trial, which the Food and Drug Administration recently cleared to start. That study, in turn, will help Moderna find the final dose to test in a Phase 3 trial that could begin in July.
The dose that Moderna selects will be important to watch, as the lower the dose, the easier it will be for Moderna to produce and distribute widely. Earlier this month, Moderna said a deal with drug manufacturer Lonza would help it make up to 1 billion doses a year, but that figure assumed a 50-microgram dose of mRNA-1273 would be successful.
"We are investing to scale up manufacturing so we can maximize the number of doses we can produce to help protect as many people as we can from SARS-CoV-2," Bancel said in the statement.
Just three days ago, the Trump administration formed "Operation Warp Speed" as part of major government push to make a coronavirus vaccine available by the end of the year. Moderna's experimental vaccine represents perhaps the best hope to fulfill that extremely aggressive timeline.
Moderna has been able to move faster than most drugmakers because it uses a technology that can design and produce vaccines more quickly than with traditional techniques. Its technology, which uses messenger RNA, or mRNA, molecules to teach the body to make certain proteins, is unproven, however, having yet to result in an approved vaccine for any disease.
Even if Moderna succeeds in its accelerated development of mRNA-1273, then, the vaccine would likely arrive with still unanswered questions about its safety and effectiveness across wide groups of people.
Other companies are testing mRNA vaccines as well. BioNTech and partner Pfizer, CureVac AG and Translate Bio, via a deal with Sanofi, are in the mix as well. BioNTech's candidate entered human testing in the U.S. this month, and in Germany last month.
Moderna stock soared Monday, hitting an all-time high after rising by more than 25%. The jump also pulled shares in both BioNTech and Translate Bio higher.