Eli Lilly has suspended its bid in the USA to get a new approval for its antidepressant Cymbalta until next year.

The company has withdrawn its supplemental New Drug Application for Cymbalta (duloxetine) for the management chronic pain. Lilly said that the decision was taken after reviewers at the US Food and Drug Administration “raised questions about the drug's effectiveness and dosing that revolved primarily around statistical methodology and study design”.

Lilly submitted the chronic pain application in the second quarter of this year based primarily on outcomes of three trials – one (positive) study in chronic osteoarthritis pain of the knee and two others in chronic low back pain. One of those was positive but the other one, while “supportive”, did not meet its primary endpoint.

The Indianapolis-based drugmaker says it plans to resubmit the application to the FDA in the first half of 2009, adding data from a recently completed study in chronic osteoarthritis pain of the knee. Lilly added that the decision does not affect Cymbalta’s existing FDA-approved indications for major depressive disorder, generalised anxiety disorder, management of diabetic peripheral neuropathic pain and fibromyalgia.

John Hayes, a Lilly Research Laboratories vice president, said the withdrawal of the sNDA “was a difficult decision, but we believe the updated data package will give the FDA a broader basis for reviewing our application".

Cymbalta is a huge earner for Lilly and third-quarter sales of the drug increased 40% to $716.4 million. However the company and marketing partner Boehringer Ingelheim suffered a bit of a regulatory blip on this side of the Atlantic recently when the European Medicines Agency’s Committee for Medicinal Products for Human Use adopt a negative opinion on Cymbalta for the fibromyalgia indication.