A one-shot vaccine developed by Johnson & Johnson generated strong protection against Covid-19 in a large, late-stage trial, raising hopes that it can rapidly reshape a stumbling immunisation campaign.
In the more than 44,000-person study, the vaccine prevented 66 per cent of moderate to severe cases of Covid-19, according to a company statement on Friday. And it was particularly effective at stopping severe disease, preventing 85 per cent of severe infections and 100 per cent of hospitalisations and deaths.
Based on the result, J&J said it plans to file for an emergency-use authorisation in the United States in early February.
The drug giant’s top scientist said this month that he expects a clearance in March, and that it would have product ready to ship then. The company didn’t specify how much of the vaccine would be available immediately, though it reaffirmed that the US would receive 100 million doses in the first half of the year.
If cleared, J&J’s vaccine could go a long way toward ending the pandemic.
Competing vaccines from Moderna and Pfizer have generated stronger overall efficacy rates, but require two shots to be given before their full benefits take hold. J&J's shot also can be kept in a refrigerator for three months, while those from Pfizer and Moderna must be kept frozen.
Single shot
"This is a single shot that can be given easily, it protects completely from that which we fear, having to go to the emergency room or a hospital," said Mathai Mammen, head of global research and development for J&J's pharmaceutical division, in an interview. "It's going to change the nature of the disease."
Concerns about keeping second doses of the current shots on hand have complicated the push to get as many people as possible inoculated. Some countries have chosen to spread out the time between doses to address the problem, at the risk of diminishing their effectiveness.
The rise of new coronavirus variants has added to the pressure to get immunizations moving faster. The J&J trial was conducted around the globe, including at dozens of clinical-trial sites in hot spots such as South Africa and Brazil where new variants have caused infections to rise.
J&J’s results produced more evidence that the variants will be harder to ward off. In the US, where mutations aren’t thought to be as widespread, the vaccine was 72 per cent effective. But in South Africa, where a variant called B.1.351 is circulating widely, it was only 57 per cent effective. And the shot was 66 per cent effective in Latin America.
Nonetheless, J&J’s vaccine is likely to give countries around the world a powerful new tool to fight a virus that has infected more than 101 million people and killed 2.2 million worldwide.
If confirmed, the results suggest people could get one dose of the vaccine to provide initial protection against severe consequences, allowing them to return to their pre-pandemic lives. Then, if needed, they could later take a booster shot J&J is testing in other large, late-stage trials that could produce results before year-end.
J&J said a review by a monitoring board identified no significant safety concerns. While 9 per cent of people who took the shot developed a fever, there were no severe allergic reactions.
Different Technology
J&J’s vaccine is different from the messenger RNA-based shots made by Moderna and partners Pfizer and BioNTech, which each were shown to be more than 90 per cent effective.
It is based on an adenovirus, or cold germ modified to make copies of the coronavirus spike protein, which the pathogen uses to force its way into cells. The altered virus can’t replicate in humans, but it triggers an immune response that prepares the body to defend itself against the coronavirus. J&J uses the same technology in a vaccine to fight Ebola.
J&J’s head of research and development said the company’s trial, conducted at the height of the pandemic, had to deal with resistant variants that arose mainly after Moderna’s and Pfizer’s trials were completed.
When counting cases, it also focused on somewhat sicker patients than other trials, Mammen said.
“If those vaccine programs accrued cases at the same time as us, when viral infections were so much higher, incidents were higher, and variants were all around us, they would have gotten different numbers,” he said. “The fact that we could do this level of efficacy with a single shot, people don’t have to come back for another, and it’s conveniently stored, well that makes this the vaccine of choice.”
At the outset of the pandemic, US government officials said any vaccine showing greater than 50 per cent efficacy would be considered a success.
Like Pfizer and Moderna, Dr Mammen said J&J is working on next-generation versions of the shot that could provide protection specifically against certain variants. Other vaccines have seen mixed results against the newer forms of the virus.
On Thursday, Novavax reported that a large late-stage study in the UK found its Covid vaccine was 89 per cent effective. However, it was just 60 cent effective in South Africa in people who were HIV negative, and 49.4 per cent effective when HIV positive patients were included. Most cases of the virus seen in the trial had the new South Africa mutation, the company said.
J&J “is already testing and creating vaccines with the ability to respond quickly to the South African strain,” Dr Mammen said.
Gaining Clearance
J&J aims to have a total of seven manufacturing facilities running by the end of the second quarter, chief financial officer Joseph Wolk said earlier this week. The company says it remains on track to hit the goal of producing one billion doses globally before year-end, even as production has been slow to scale up throughout the winter.
J&J’s candidate was among six vaccines tapped for the Trump administration’s Operation Warp Speed program, receiving some $1.5 billion in backing from the US government.
The company intends to price the vaccine on a not-for-profit basis, defined by a Gates Foundation model and determined in conjunction with independent auditors, according to Mr Wolk. The price per shot will not exceed $10, he said. – Bloomberg
