By Matt Grossman

Eli Lilly & Co. Tuesday posted revenue gains but a smaller profit for the first three months of 2021, as sales gains from Covid-19 treatments were offset by higher research and developments costs and one-time charges.

The Indianapolis-based pharmaceutical company logged earnings of $1.49 a share, a decline from $1.60 a share in last year's first quarter. Net income fell year over year to $1.36 billion, from $1.46 billion in the year-ago quarter.

On an adjusted basis, Lilly's earnings were $1.87 a share. Analysts surveyed by FactSet had forecast an adjusted profit of $2.13 a share.

Revenue climbed 16% to $6.81 billion, from $5.86 billion a year earlier. Analysts were expecting revenue of $6.97 billion.

Lilly's Covid-19 antibody treatments drove revenue of $810.1 million in the quarter. Increased buying patterns and prescription trends because of the course of the Covid-19 pandemic resulted in world-wide revenue growth of about $250 million, including about $200 million in the U.S. and $50 million abroad.

In the U.S., higher volumes for drugs such as Trulicity, Taltz, Verzenio, Retevmo, Emgality, Jardiance and Olumiant were counterweighted by reduced sales of products such as Alimta, Basaglar, Forteo and Cialis.

Sales of Covid-19 antibodies contributed to a less favorable product mix for profitability, with the company's gross margin as a percent of revenue declining by 6.9 percentage points to 72.4%. Research and development expenses rose 21% year over year.

Lilly recorded asset impairment, restructuring and other charges of $211.6 million, compared with $59.9 million a year earlier.

Write to Matt Grossman at matt.grossman@wsj.com

(END) Dow Jones Newswires

04-27-21 0706ET