Roche said it expects a global shortage of Actemra — its blockbuster anti-inflammatory drug recently authorized by the FDA for treatment of severe COVID-19 infection — because of surging demand.

The company cited global manufacturing capacity limits, raw material supply constraints, the complex process of manufacturing biologics and the “evolving nature of the pandemic” as factors contributing to the shortage.

In the past two weeks alone, U.S. demand has increased by more than 400 percent above pre-pandemic levels, Roche said.

Originally developed as an arthritis treatment, Actemra (tocilizumab) earned almost $3.2 billion in global sales in 2020.