Janssen avoids Covid infections and deaths as well as Pfizer, new data shows

About 17 million Americans received Janssen’s Covid-19 vaccine, but were later told it was the least protective of the options available in the United States. However, new data suggest that the vaccine today is preventing infections, hospitalizations and deaths at least as well as the immunizers from Pfizer-BioNTech and Moderna.

The reasons are unclear and not all experts are convinced that the vaccine is beyond doubt. But the accumulated data nevertheless offer considerable reassurance to vaccine recipients and, if confirmed, have far-reaching implications for its use in other parts of the world.

In Africa, for example, distributing a single-dose vaccine that can be refrigerated for months is by far the most practical option.

Johnson & Johnson has at least temporarily closed the only factory that produces usable batches of the vaccine. But Aspen Pharmacare, based in South Africa, is preparing to supply large quantities to the rest of the continent. Only about 13% of Africans are fully vaccinated and only about 1% have received a booster dose.

“In the African setting, where we need to get vaccines out quickly, the single dose is very exciting,” said Linda Gail-Bekker, director of the Desmond Tutu HIV Center at the University of Cape Town, who has studied vaccine effectiveness in South Africa.

Janssen’s vaccine has been heralded as an interesting option for communities with little access to healthcare, including some in the United States, because of its ease of delivery and mild side effects. But his path was bumpy.

The injection appeared to produce a weaker initial immune response, and more people who received the single-dose vaccine had recurrent infections, compared with those who received two doses of either Pfizer or Moderna’s mRNA vaccines.

In April, federal health officials in the United States and South Africa halted distribution of Janssen’s vaccine as they examined reports of a rare blood clotting disorder in women. Although the two countries resumed launches soon after, the vaccine’s reputation never fully recovered.

But the idea that the vaccine is inferior has become outdated, some experts said. More recent data suggests that it has more than maintained its position relative to competitors.

“We are aware that J&J has been somewhat debased in people’s minds,” said Dr. Gail-Bekker. But “it is more than satisfactory for a single-dose vaccine.”

Through June, cumulative data from the Centers for Disease Control and Prevention (CDC) showed that immunization with the Moderna vaccine resulted in the lowest rates of reinfections; people who took Janssen had the highest rates, with Pfizer-BioNTech somewhere in between.

During the summer months, the differences –particularly between Janssen and Pfizer– began to narrow. So far, all vaccines appear to be working equally well against coronavirus infections; in fact, Janssen’s seems to be holding up a little better.

According to the most recent data available, as of January 22, unvaccinated people were 3.2 times more likely to be infected than those who received the single dose of Janssen; 2.8 times more likely to be infected than those who received two doses of the Moderna vaccine; and 2.4 times more than those who took two doses of Pfizer-BioNTech. In general, Janssen appeared to provide slightly more protection against infection than the two alternatives.

Among Americans who received booster shots, all vaccines appeared to be approximately equally effective against the infection. A booster shot did not greatly increase Janssen’s previous level of protection (although the data does not indicate who received which type of booster shot). Data was collected by the CDC in 29 jurisdictions, representing 67% of the US population.

“The CDC data adds to the growing body of evidence indicating that Janssen’s Covid-19 vaccine offers long-lasting protection against infections and hospitalizations,” the lab said in a statement.

The results indicate that Janssen’s vaccine deserves a closer look, said Dr. Larry Corey, a vaccine development specialist at the Fred Hutchinson Cancer Research Center in Seattle.

“This vaccine platform may have some surprising features that we hadn’t anticipated,” he said. The data “is interesting, provocative, and we should take more time to understand it.”

_{Translated by Luiz Roberto M. Gonçalves}