Johnson & Johnson has begun the first human trial of its experimental coronavirus vaccine, a study that will enroll 1,000 adults, young and old, in the U.S. and Belgium. It also published data from an animal study in a major medical journal. Though J&J trails multiple frontrunners in the urgent push to develop a preventive treatment for coronavirus disease, it could catch up quickly. Two other early trials should soon start, and assuming the vaccine proves safe in those tests, a large-scale efficacy study would follow in September. The company is testing both one- and two-dose regimens of the vaccine in early studies, but touted its potential, based on an animal study, to provide protection from SARS-CoV-2 infection with a single shot. That has yet to be proven in clinical trials, however, and AstraZeneca had the same goal with a similar vaccine before seeing better results when adding a “booster” shot.
Like others speeding forward with coronavirus vaccines, J&J has moved at an historic pace, accomplishing in months what normally takes years. Its efforts, though, have thus far been overshadowed by companies like Moderna, AstraZeneca, and partners BioNTech and Pfizer, which have each advanced their vaccines a bit faster and published early data.
But J&J was the first large drugmaker to pursue a vaccine, beginning its work in January. Relying on the technology that underlies its approved Ebola vaccine and others in testing — in which a virus delivers, into cells, the genetic blueprints for a protein — has publicly portrayed a lot of confidence in this work. On an earnings call two weeks ago, J&J’s top scientist, Paul Stoffels, said he believed the vaccine could easily surpass the bar set by the Food and Drug Administration for widespread use.
The agency wants to see a vaccine reduce the risk of infection or COVID-19 disease by at least 50% compared to a placebo. Stoffels said J&J is expecting somewhere in the range of 70% to 80%.
It’s unclear whether any vaccine in development, including J&J’s, can protect against coronavirus infection or COVID-19 in humans. Early results from J&J’s more advanced rivals have only shown that their vaccines are safe enough to move forward and produce immune responses that might be meaningful.
J&J is hoping to show not only that its vaccine might help provide protection, but also do so with a single shot. The journal Nature on Thursday published results from a non-human primate challenge study, in which 52 monkeys exposed to the virus were given with different variations of the vaccine J&J has been developing. The one J&J has selected for human tests produced antibodies to neutralize the coronavirus and showed “complete protection” from the virus for five of six monkeys who got it, while the sixth had “near-complete protection,” the study authors wrote.
The levels of antibodies correlated with the vaccine’s effectiveness, at least suggesting a “correlate of protection,” the authors wrote, a critical guidepost scientists and regulators need to predict whether a vaccine might protect people from infection or disease.
A successful one-shot regimen would be the optimal product to distribute at scale in a mass vaccination campaign. But that’s been tough for drugmakers to achieve thus far. AstraZeneca, which is advancing a similar, rival vaccine developed by the University of Oxford, also aimed for a one-shot vaccine before early results suggested two doses were superior. It’s considering both one- and two-dose regimens for its Phase 3 trial.
Vaccines from Moderna and the BioNTech and Pfizer partnership look as if they’ll each require at least one booster shot.
The study authors expressed caution for J&J’s shot as well, noting that they would “expect that a two-dose vaccine” would trigger a greater immune response.
It’s unclear how big of a response is needed to protect from infection or coronavirus disease, however, so J&J is thus hedging its bet. The company is testing both one- and two-shot regimens in early trials, which include the study it just started, a separate Phase 1 trial in Japan, and a Phase 2 study in the Netherlands, Spain and Germany. It then plans to run two Phase 3 placebo-controlled trials, in parallel, for each.
J&J has received some $456 million in funding from the U.S. government to support its vaccine, and said on Wednesday that it is in talks with “global strategic partners to support worldwide access.” If the vaccine succeeds, J&J plans to supply more than 1 billion doses, globally, over the course of 2021.
