The Food and Drug Administration on Thursday authorized Merck’s COVID-19 pill for certain adults.

The authorization is limited to adults who have a high risk of severe illness and for whom alternative FDA-authorized treatment options are not accessible or medically appropriate.

This is the second COVID-19 treatment in pill form after Pfizer’s pills were authorized Wednesday.

This is a developing story. Please check back for updates.

ABC News’ Sony Salzman contributed to this report.

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