Since the outlook of the weight-loss medicine lorcaserin is thronged open into question mark after a Food and Drug Administration Panel suggested against its endorsement on Thursday, shares of Arena Pharmaceuticals Inc. jumped to the lowest level ever on Friday.

The pharmaceutical firm Arena Inc is facing tough problems and possible lawsuits from its investors who are very disappointed with the company as the firm did not disclose the fact that its experimental weight loss medicine caused cancer in rats.

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.

Giant drug-maker Arena Pharmaceuticals Inc. on Tuesday confirmed that it has submitted an application with the US Food and Drug Administration to gain approval for the marketing of its experimental drug for weight loss, lorcaserin.

Recently, the success of the second large late-stage study of its weight-loss drug, lorcaserin, was announced by Arena Pharmaceuticals Inc. However, Wall Street was disappointed when the strength of the results was compared to other drugs being developed.