Neurocrine Biosciences said the FDA has requested additional data regarding the company's New Drug Application for indiplon 5 mg and 10 mg capsules for the treatment of insomnia. The request comes six months after Neurocrine resubmitted its application for 5-mg and 10-mg doses. The FDA denied approval in May 2006 over issues with the 15-milligram dose, which was expected to bring in the bulk of Neurocrine's revenue after approval. Pfizer terminated a partnership with Neurocrine over indiplon in June 2006. Neurocrine later announced it was cutting its field sales force, followed by 100 workers at its company headquarters. The FDA's latest approvable letter request states indiplon is approvable in the two requested doses, pending the submission of additional clinical trial and preclinical study data. The requirements include an objective/subjective clinical trial in the elderly, a safety study, and preclinical study data evaluating indiplon during the third trimester of pregnancy, Neurocrine said.