Marlborough-based biotech Advanced Cell Technology, which trades on the OTC Bulletin Board, reported a net loss of $5.7 million for the quarter ending March 31, up from $3.3 million a year ago.
The company also used more cash during the quarter – $4.8 million compared to $3.4 million.
ACT earns some revenue from licensing fees, but has not yet been profitable. It is in the midst of the first human stem cell trial approved by the U.S. Food and Drug Administration.
The company is developing treatments for Stargardt's macular dystrophy and dry age-related macular degeneration, which deteriorate layers of cells in the back of the eye.
"We are encouraged by the results we have seen from the early patients treated in each of our indications, and look forward to completing the trials on schedule," CEO Gary Rabin said in a statement.
Rabin said in a recent interview that he wants to make a play for a NASDAQ listing, which would attract institutional investors. With that aim in mind, shareholders approved a reverse stock split in April.