Arena Pharmaceuticals, Inc., a clinical-stage biopharmaceutical company, Thursday, announced a narrower fourth quarter loss, triggered by a sharply lower research and development expenses on account of the conclusion of late-stage studies of evaluating lorcaserin for weight management.

The San Diego Company registered a loss of $29.8 million, or 32 cents per share, in the three months ended Dec. 31, compared with a loss of $62.5 million, or 84 cents per share, in the final quarter of 2008.

However, analysts polled by Thomson Reuters anticipated a loss of 31 cents per share on about $3.5 million in revenue.

The company revealed that its sole aim is to fetch FDA approval for lorcaserin in 2010 and to commercialize it.

Research and development expenses for the quarter reported a sharp fall to $21.19 million from $53.33 million in the prior year.

The company hopes the research and development expenses to stick to its declining trend in 2010 due to the completion of the BLOOM and BLOSSOM and other cost-containment measures.