Pfizer announced a deal on Tuesday to allow its promising Covid-19 treatment to be made and sold inexpensively in 95 poorer nations that are home to more than half of the world’s population.

The agreement follows a similar arrangement negotiated by Merck last month, and together the deals have the potential to vastly expand global production of two simple antiviral pills that could alter the course of the pandemic by preventing severe illness from the coronavirus.

Under the agreement, Pfizer will grant a royalty-free license for the pill to the Medicines Patent Pool, a nonprofit backed by the United Nations, in a deal that will allow manufacturers to take out a sublicense. They will receive Pfizer’s formula for the drug, and be able to sell it for use in 95 developing countries, mostly in Africa and Asia, once regulators authorize the drug in those places.

Under the deal struck with the global Medicines Patent Pool (MPP), Pfizer — which also produces one of the most widely-used Covid vaccines with German lab BioNTech — will not receive royalties from the generic manufacturers, making the treatment cheaper.

The agreement is subject to the oral antiviral medication passing ongoing trials and regulatory approval.

The Pfizer drug is to be taken with the HIV medicine ritonavir.