Biotech Research Laboratories of Rockville, a maker of biotechnology-based products, yesterday reported that it earned $1.6 million (27 cents a share) in 1987, compared to a loss of $380,273 (7 cents) last year.

Revenue for the year rose 86 percent, to $11.6 million, from $6.2 million last year.

The company last summer received an exclusive license from the Food and Drug Administration to manufacture the Western Blot validation test for AIDS antibodies.

According to Thomas Li, the company's president, the sale of those kits -- in addition to the sale of ELISA AIDS screening tests, which the firm has been making since late 1985 -- accounted for $5 million of Biotech's 1987 revenue, and were a major reason for the company's first profitable year since 1982.

The company also reported that fourth-quarter earnings grew to $1.1 million (19 cents) from $63,761 (1 cent) a year ago.

Revenue more than doubled in the quarter, to $4.3 million from $2 million in the same period last year.

"The company has been unprofitable as a result of the more than $1 million spent annually on R&D," said company vice president J. Bryan Dowling. "We are all very pleased with Biotech's dramatic return to profitability ... We expect these trends to continue."