Pfizer and BioNTech will supply the US with an additional 100 million doses of the COVID-19 vaccine under a new agreement.
The drugmakers say that they expect to deliver all the doses by July 31.
Pfizer already has a contract to supply the government with 100 million doses of its vaccine.
Pfizer’s vaccine was the first to gain approval from the Food and Drug Administration and initial shipments went to states last week. It has now been joined by a vaccine from Moderna, which was developed in closer cooperation with scientists from the National Institutes of Health.