Back in January, we told you about a different kind of COVID vaccine that had just been approved for use in India. The vaccine, called Corbevax, had some very attractive properties: It's low-cost, easy to make using well-established biotech processes — and patent-free.

The vaccine's inventors were hoping it would help address questions of vaccine equity for countries that can't afford to make or buy expensive vaccines like the ones sold by Pfizer and Moderna.

It appears their strategy is working. Since Corbevax was authorized for use last December, Indian health authorities have administered quite a few doses. Here's where things stood on August 10 when I spoke with the two scientists who invented it: Peter Hotez and Maria Elena Botazzi, co-directors of the Center for Vaccine Development at Texas Children's Hospital.

"The new numbers as of this week from the Indian government say that 70 million doses have gone into arms," Hotez says. Those arms belong to adolescents, but on August 10 the vaccine was authorized for use as a booster in people 18 and older.

Not only does the experience so far suggest the vaccine confers long-lasting immunity, it also appears to be quite safe.

"We have not seen any pharmacovigilance that says otherwise," Botazzi says. Pharmacovigilance is the technical term for monitoring for bad side effects from a drug or vaccine.

In addition to using low-cost materials, Botazzi says they also wanted to be culturally sensitive. For example, they made sure no products derived from animals were needed to make the vaccine.

"Our technology is considered vegan and therefore we can develop this vaccine as a halal certified vaccine," she says – an important consideration in countries with a large Islamic population like Indonesia.

Wondering how the world would respond

It wasn't certain at first countries would take to Corbevax.

"A lot of people initially thought the global market for COVID vaccines is quite saturated," says Prashant Yadav, a senior fellow at the Center for Global Development. "Will there be a place for a late entrant, even if it comes at a lower cost and even if it comes with more open intellectual property?"

The answer to that question appears to be yes. In addition to a partnership with Biological E in India, a company called Biofarma in Indonesia is planning to make Corbevax.

And African countries are showing interest.

"Corbervax has been approved by the Botswana Medicines Regulator Authority," says Mogomatsi Matshaba, an adviser to the Botswana government on COVID-19 and executive director of Botswana-Baylor. He says Corbevax has not yet been used there, but he expects it will be, as well as in other African countries.

"The plan is to start mass production in Botswana," he says.

Of course lately, there have been new variants of the COVID virus, and it's not clear how well Corbevax will work against them. The Texas team that made Corbevax is trying to make a version of their vaccine that will work against all varieties of the virus.

At least one member of the U.S. Congress was so impressed with Hotez and Botazzi that she nominated the pair for the Nobel Peace Prize

"Their effort is to bring health, peace and security to all people by making it possible to vaccinate the world," says Lizzie Fletcher, a Texas Democrat. "So I think that that's very much in keeping with the purpose of the prize."

Winning a Nobel prize is probably a long shot, but that's OK with Hotez.

"I'm on cloud nine and I think Dr. Bottazzi is as well in part because, you know, it's not just the recognition, it's the fact that we showed there's another way to do this," he says — a way for a small, academically focused lab to make a vaccine that's safe, effective and affordable.