By Josh Nathan-Kazis –
Johnson & Johnson became the third Western biopharmaceutical company to begin a new trial of its Covid-19 vaccine this week, but with a difference: In a surprise announcement on Thursday morning, the company said it would test its vaccine in a single-dose format.
Moderna (MRNA) and Pfizer (PFE) both began Phase 3 trials this week of Covid-19 vaccines that would need to be delivered in two-dose regimens. Johnson & Johnson (JNJ) said Thursday that, following the publication of promising data from a trial of the drug in monkeys, it had begun a first-in-human Phase1/2a trial of the vaccine in the U.S. and Belgium that would test both one- and two-dose regimens of the vaccine, and would include more than 1,000 people.
A Covid-19 vaccine that could be effective as a single dose would have an advantage over competitors, as it could substantially decrease the complexity of the world-wide inoculation program likely necessary to end the pandemic.
“We are excited to see these preclinical data because they show our SARS-CoV-2 vaccine candidate generated a strong antibody response and provided protection with a single dose,” Johnson & Johnson’s chief scientific officer, Paul Stoffels, said in a statement. “The findings give us confidence as we progress our vaccine development and upscale manufacturing in parallel.”
Shares of Johnson & Johnson, the world’s largest pharmaceutical company, climbed 1.8% in premarket trading on Thursday morning. The stock is up 0.5% so far this year, and trades at 17.2 times earnings expected over the next 12 months, according to FactSet, up from its five-year average of 16.2 times earnings.
“This is clearly good news,” Cantor Fitzgerald analyst Louise Chen wrote in a note Thursday morning.
A paper to be published by Nature, and posted online by the journal in an unedited form on Thursday morning, described a study of a single-dose regimen of the Johnson & Johnson vaccine involving 52 rhesus monkeys.
After six weeks, the monkeys were dosed with the virus that causes Covid-19. Various experimental versions of the Johnson & Johnson vaccine were tested; among the six monkeys given the version that the company is moving forward with, none developed a detectable infection in the lower respiratory tract, while one showed a low amount of virus in a nasal swab.
“Ad26-S.PP induced robust [neutralizing antibody] responses after a single immunization and provided complete protection against SARS-CoV-2 challenge in 5 of 6 animals, whereas one animal had low levels of virus in [nasal swab],” the Nature authors wrote. “These data suggest minimal to no virus replication in the Ad26-S.PP vaccinated animals following SARS-CoV-2 challenge.”
Johnson & Johnson says it plans to start a Phase 3 trial of a single-dose regimen in September. The timeline is accelerated from its earlier plan to begin Phase 1 trials in September, and seek approval in the middle of next year. It has not yet said when it now plans to seek approval for its vaccine.
The vaccine, a so-called non-replicating viral vector vaccine, uses an altered version of a cold virus called Ad26 to deliver viral genetic material to a cell. Though no Ad26-based vaccine has been approved by U.S. regulators in the past, the technology was used in the company’s Ebola vaccine, which has been given to 50,000 people, and which European regulators approved July 1.