Teva Pharmaceutical (NYSE:TEVA) plans to donate 10 million tablets of the malaria drug hydroxychloroquine sulfate as a potential treatment for COVID-19. That news follows a report from earlier this week that Bayer (OTC:BAYRY) plans to donate 3 million tablets of the related drug chloroquine, which is more potent but has more hazardous side effects.

Teva has 6 million tablets on hand, which it plans to ship through wholesalers to hospitals by March 31, with the remaining doses expected to be ready within a month.

Hydroxychloroquine and chloroquine are best-known as treatments for malaria, which is caused by a parasite, not a virus. Hydroxychloroquine is also prescribed for autoimmune diseases. But recent studies reported on in the journal Nature have found both drugs inhibit the ability of the SARS-CoV-2 coronavirus to replicate in the laboratory. How well the drug might do to help humans fight off the disease is still unknown, although initial reports have been positive.

On Thursday, Mylan (NASDAQ:MYL) said it restarted production of its hydroxychloroquine sulfate tablets with plans to ramp up production to 50 million tablets, which could treat more than 1.5 million people. Mylan didn't mention anything about donating its product, but both chloroquine and hydroxychloroquine have been around for decades and are off-patent. Even if Mylan charges for its generic drug, the treatment is likely to be cheap. This won't move Mylan's financials much considering it registered $11.5 billion in revenue last year, and will only get bigger after its merger with Pfizer's (NYSE:PFE) Upjohn division.

While they're not going to make much profit with these moves, Bayer, Teva, and Mylan should certainly earn some goodwill and positive PR.