Press Release: Depomed Announces Positive Phase II Results for Once Daily Gabapentin GR

Depomed Announces Strong Positive Phase II Trial Results for Once Daily Gabapentin GR to Treat Symptoms of Diabetic Peripheral Neuropathy MENLO PARK, Calif. --Depomed, Inc. (Nasdaq:DEPO) today announced statistically significant efficacy benefits of its Gabapentin GR™ extended release tablets for the once daily treatment of pain in patients with diabetic peripheral neuropathy (DPN), a nerve disorder caused by diabetes. The multicenter, double-blind, placebo-controlled Phase II clinical trial involved 147 randomized patients with diabetic peripheral neuropathy. Patients were randomized into one of three treatment groups: 3000 mg Gabapentin GR dosed once or twice daily or placebo. The primary objective of the four-week study was to assess the efficacy of Gabapentin GR in treating the pain associated with DPN. Reductions in average daily pain scores from baseline to the end of treatment based on the 11 point Likert pain scale were statistically significant with once daily Gabapentin GR. Clinically significant improvements in the pain score were observed with a mean change from baseline to study end of –2.45 compared to –1.26 for placebo (p= 0.002). Although not statistically significantly different for twice daily Gabapentin GR, there was pain improvement with a reduction in mean daily pain score of –1.75 with Gabapentin GR compared to –1.26 with placebo (p= 0.190). These data were calculated using a baseline observation carried forward analysis, meaning that a zero percent improvement was assigned to patients who did not complete the study. The secondary endpoint analysis of responders, defined as patients with at least a 50 percent reduction in pain at endpoint compared to baseline, showed that both once and twice daily Gabapentin GR arms reached statistical significance. The proportion of responders was 35 percent for once daily Gabapentin GR (p= 0.001), 26 percent for twice daily Gabapentin GR (p= 0.015) and 8 percent for placebo. “These results are impressive and position Gabapentin GR favorably in efficacy, safety and dosing convenience against existing therapeutic options which are dosed at least three times per day,” said John W. Fara, Ph.D., chairman, president and chief executive officer of Depomed. “The data strongly support once daily Gabapentin GR and indicate that twice daily dosing may also be an option for patients. We are enthusiastic about sharing these data with companies that have expressed an interest in partnering Gabapentin GR with us and are encouraged to advance our development program for DPN forward.” Sherwyn Schwartz, M.D., clinical investigator in the trial and director, Diabetes & Glandular Disease Research Associates of San Antonio, said, “The pharmacodynamic properties of Gabapentin GR provide long lasting drug exposure to help manage the pain. This is especially important with Gabapentin GR given once daily with an evening meal as pain is generally more pronounced in patients at night. Patients are being dosed at what appears to be an optimal time with a controlled release formulation that provides extended pain relief throughout the day.” Sleep interference, another secondary endpoint, decreased with both once and twice daily Gabapentin GR, with the once daily Gabapentin GR reaching statistical significance. In the once daily arm, Sleep Interference Scores were reduced by –2.70 compared to –1.65 with placebo (p=0.01). There were no serious adverse events associated with Gabapentin GR. The most common side effects observed were dizziness and somnolence, which are commonly associated with gabapentin. The reported incidences were 17.0 percent and 12.8 percent for dizziness and somnolence respectively for once daily Gabapentin GR and 12.2 percent and 4.1 percent, respectively for twice daily Gabapentin GR. In each of the three treatment groups, once and twice daily Gabapentin GR and placebo, there were only two patients who discontinued the study due to adverse events. Carl Pelzel, executive vice president and chief operating officer of Depomed, added, “We attribute these strong safety and efficacy results to our unique formulation of gabapentin which is based on our AcuForm™ drug delivery technology. In pharmacokinetic studies, we showed improved bioavailability of our Gabapentin GR at higher doses with a greater percentage of the administered dose reaching the blood stream compared to immediate release gabapentin. Today’s efficacy and safety data complement the pharmacokinetic data and show that the high doses do indeed serve to reduce pain and, in our unique formulation, are well tolerated in this Phase II clinical study.” About Diabetic Peripheral Neuropathy Diabetic neuropathy is a peripheral nerve disorder caused by diabetes. Approximately 60 to 70 percent of the 20 million diabetics in the United States have mild to severe forms of nervous system damage. After a period of inadequate glycemic control, nerve damage may occur and may lead to a number of health problems, including indigestion, diarrhea or constipation, dizziness, bladder infections and impotence. DPN is often associated with numbness, pain, or tingling in the feet or legs and may lead to weakness in the muscles of the feet. Current treatment approaches for DPN involve providing options for pain relief and implementing glycemic control measures, including diet, exercise and medication, to prevent further tissue damage by bringing blood sugar levels under control. About Depomed Depomed, Inc. is a specialty pharmaceutical company utilizing its innovative AcuForm™ drug delivery technology to develop novel oral products and improved, extended release formulations of existing oral drugs. AcuForm-based products are designed to provide once daily administration and reduced side effects, improving patient convenience, compliance and pharmacokinetic profiles. ProQuin® XR (ciprofloxacin hydrochloride) extended-release tablets have been approved by the FDA for the once daily treatment of uncomplicated urinary tract infections and are currently being marketed in the United States. In addition, once daily GlumetzaTM (metformin hydrochloride extended release tablets) has been approved for use in adults with type 2 diabetes and is currently being marketed in the United States and Canada. The company is conducting a Phase III trial in postherpetic neuralgia and has completed a Phase II trial in diabetic peripheral neuropathy with its product candidate, Gabapentin GR™. Additional information about Depomed may be found at its web site, “Safe Harbor” Statement under the Private Securities Litigation Reform Act of 1995. The statements that are not historical facts contained in this release are forward-looking statements that involve risks and uncertainties including, but not limited to those related to our clinical trial results and analysis, research and development efforts, including pre-clinical and clinical testing; regulation by the FDA and other government agencies; the timing of regulatory applications and product launches; and other risks detailed in the company's Securities and Exchange Commission filings, including the company’s Annual Report on Form 10-K and its most recent Quarterly Report on Form 10-Q. You are cautioned not to place undue reliance on these forward-looking statements which speak only as of the date hereof. The company undertakes no obligation to publicly release the result of any revisions to these forward-looking statements that may be made to reflect events or circumstances after the date hereof or to reflect the occurrence of unanticipated events.