Trimeris (Nasdaq: TRMS) beat Wall Street expectations with a profit of $3.16 million for the third quarter even as sales for its only product – the HIV drug Fuzeon – plummeted 38 percent.

Before the markets opened Thursday, said it posted a 16-cents-per-share profit in its most recent quarter. Wall Street analysts polled by First Call/Thomson had predicted a 10-cent profit.

Revenues also topped analysts’ expectations by $600,000 at $5.4 million.

However, Trimeris revenues also fell by nearly half from a year ago as sales for Fuzeon continue to drop. The costly, difficult-to-administer drug that requires injection has faltered in global markets against increasing competition. Trimeris has cut costs and overhead drastically over the past year as a result.

Trimeris sells Fuzeon in partnership with drug giant Roche. Trimeris reported the most recent drop in sales two weeks ago.

Through nine months this year, Trimeris has made a profit of $6.5 million compared with $18.4 million for the same time frame in 2007.