By Deena Beasley

April 30 (Reuters) - Gilead Sciences Inc, maker of the experimental coronavirus drug remdesivir, on Thursday reported flat first-quarter earnings and said it with work with international partners to expand production of potential COVID-19 treatment.

The company said it still expects to have more than one million remdesivir treatment courses manufactured by December, "with plans to be able to produce several million treatment courses in 2021."

The U.S. National Institutes of Health on Wednesday said preliminary results from its trial of remdesivir showed that COVID-19 patients given the drug recovered 31% faster than those given a placebo. Data from a trial run by Gilead, also unveiled on Wednesday, showed similar clinical improvements in patients with severe symptoms of COVID-19, regardless of whether they received five or ten days of treatment.

On Thursday, the biotechnology company said its first-quarter profit was largely flat from a year ago as a 5% increase in sales was offset by higher costs, including spending related to development of remdesivir.

Gilead posted adjusted earnings of $1.68 a share on revenue of $5.55 billion in the quarter. Wall Street analysts, on average, forecast a profit of $1.57 on revenue of $5.45 billion, according to Refinitiv IBES.

First quarter sales of Gilead's HIV drugs rose to $4.1 billion from $3.6 billion a year earlier. (Reporting By Deena Beasley Editing by Bill Berkrot)