Lilly Cymbalta Diabetic Pain Launch To Piggyback On Depression Roll-Out

Lilly's launch of two Cymbalta indications will highlight the utility of duloxetine in treating both emotional distress and physical pain.

A supplemental Cymbalta indication for management of neuropathic pain associated with diabetic peripheral neuropathy cleared FDA under priority review Sept. 3.

Cymbalta "is the first drug specifically approved for this indication," an ¹ FDA Talk Paper announcing the approval states.

The serotonin and norepinephrine reuptake inhibitor was first approved Aug. 3 for major depressive disorder (² (Also see "Cymbalta Labeling Hints At Side Effect Claim; Lilly Will Test In Phase IV" - Pink Sheet, 9 Aug, 2004.), p. 4). Formal launch was delayed several weeks to allow sufficient inventory build up, the company said.

Lilly plans to concentrate on launching Cymbalta for depression first and said it will start promoting Cymbalta for the neuropathic pain indication in the fourth quarter.

Lilly had been considering an alternate duloxetine trade name for the pain indication but decided sharing the Cymbalta name would be appropriate, given the drug's dual effect.

"Cymbalta, as an antidepressant, is effective at treating both the emotional and painful physical symptoms of depression," the company noted in announcing the new approval.

"Seeing significant benefit in diabetic neuropathic pain, among patients who did not have depression, helps confirm that this drug has a positive impact on pain that is separate from improvement in mood."

During the launch phase, Lilly said it will concentrate on detailing to psychiatrists and primary care physicians to position Cymbalta as a first-line antidepressant.

For the neuropathic pain indication, Cymbalta sales reps will visit neurologists and pain specialists beginning in the fourth quarter.

Lilly is pursuing a third application for duloxetine for stress urinary incontinence under the brand name Yentreve . FDA issued an "approvable" letter in August 2003 requesting additional information (³ (Also see "Lilly Cymbalta Approval Timeline In Doubt After Delay In Second NDA" - Pink Sheet, 8 Sep, 2003.), p. 4). Lilly has responded to the letter and expects approval in early 2005.

Cymbalta efficacy in the treatment of diabetes-related neuropathic pain was demonstrated in two randomized placebo-controlled trials, each lasting 12 weeks, which compared a dose of 60 mg or 120 mg once-daily with placebo.

The studies enrolled 791 patients with Type I or Type II diabetes mellitus with a diagnosis of painful distal symmetrical sensorimotor polyneuropathy for at least six months; 592 patients completed the trials.

"Treatment with Cymbalta 60 mg one or two times a day statistically significantly improved the endpoint mean pain scores from baseline and increased the proportion of patients with at least a 50% reduction in pain scores from baseline," ⁴ labeling states.

"Patients who did not complete the study were assigned 0% improvement."

"Some patients experienced a decrease in pain as early as Week 1, which persisted throughout the study," labeling notes.

The suggested dose for the diabetic peripheral neuropathic pain indication is 60 mg/day given once a day.

"While a 120 mg/day dose was shown to be safe and effective, there is no evidence that doses higher than 60 mg confer additional significant benefit, and the higher dose is clearly less well tolerated," labeling states.

Side effects most commonly reported for the neuropathic pain trials were nausea, somnolence, dizziness, constipation, dry mouth, hyperhidrosis, decreased appetite, and asthenia.

Cymbalta is supplied in three strengths: 20 mg, 30 mg and 60 mg. Dosage guidelines for the major depressive disorder indication suggest a total daily dose of 40 mg (given as 20 mg twice daily) to 60 mg (given either once a day or as 30 mg BID), labeling states.

Lilly is pricing the 60 mg and 30 mg tablets equally to encourage once-daily dosing (⁵ , p. 23).