Depomed says its post-shingles pain drug succeeded it trial, and shares hit three-year high

Depomed says shingles pain drug meets study goal

MENLO PARK, Calif. — Depomed Inc. on Monday reported a successful late stage clinical trial of a drug intended to treat pain following the viral infection shingles, and its shares soared on the news.

The company said its DM-1796 significantly reduced post-shingles pain compared to placebo after 10 weeks of treatment. Depomed said it plans to file for Food and Drug Administration approval by the end of March 2010, and in morning trading, its shares surged to a three-year high.

Depomed shares advanced $1.20, or 27.2 percent, to $5.61, and they peaked at $6.21, their highest price since June 2006. About 5.1 million shares changed hands by 10 a.m. About 288,000 shares trade on an average full day.

DM-1796 is an extended-release form of gabapentin, which is used to treat pain disorders and epilepsy. Depomed said its drug needs to be taken only once per day, compared with other versions that have to be used four or five times a day, and the company said DM-1796 may have fewer side effects due to its lower dosing.

Depomed CEO Carl Pelzel said the tablet swells up after reaching a patient’s stomach, becoming three times its original size. That allows the tablet to remain in the stomach longer and release medication over eight or nine hours.

Depomed is studying 300 milligram and 600 milligram tablets of the drug. In the trial, patients were given doses of 1,800 milligrams per day, taken all at once. The most common side effects were dizziness and tiredness. Pelzel said a once-per-day treatment is more convenient, because patients can take the tablets before going to bed and without becoming tired during the day, and possibly missing other doses.

A total of 452 patients were enrolled in the study.

Solvay Pharmaceuticals has the license rights to DM-1796 in the U.S., Canada and Mexico as a pain treatment. That business is being bought by Abbott Laboratories for $7.6 billion.

Also jumping were shares of Xenoport Inc., which is also developing a gabapentin-based drug as a treatment for pain following shingles. Xenoport and its partner, GlaxoSmithKline, reported positive results from a mid stage trial in September.

Shares of Santa Clara, Calif.-based Xenoport gained $1.59, or 8 percent, to $21.42.

Abbott shares rose 49 cents to $50.33, and GlaxoSmithKline stock added 14 cents to $38.86.