Johnson & Johnson is developing several next generation Covid-19 vaccines against the emerging variants of the coronavirus, Chief Executive Officer Alex Gorsky has said.

The drugmaker, which won the United States emergency use authorisation of a one-shot vaccine last month, had previously said it was developing a second-generation vaccine that would target the variant first identified in South Africa. J&J is also working on a two-dose version of its vaccine, according to Reuters.

“We could be in a situation where you could either need a booster to maintain the durability (of protection against the virus) or you might need to have a next derivative of the current vaccine to address these variants as they develop”, Gorsky said at a webinar by the Economic Club of New York.