Depomed, Inc. announced that in its second phase I pharmacokinetic-pharmacodynamic study in Parkinson's patients, DM-1992, Depomed's investigative novel gastric-retentive, extended-release formulation of levodopa/carbidopa, maintained therapeutic blood levels of levodopa over 24 hours in a twice-daily formulation.

Two distinct twice-daily formulations of DM-1992 were tested in the study. Both formulations are projected at steady state to consistently maintain levodopa blood levels above the efficacious threshold of 300ng/mL for 24 hours, as mean levodopa blood levels after 24 hours exceeded 300ng/mL. DM-1992 was well tolerated in the study.

“We believe DM-1992 may meet a significant unmet need of Parkinson's patients for a twice-daily formulation of levodopa/carbidopa that maintains therapeutic blood levels throughout the night, when the symptoms of Parkinson's disease can be particularly severe,” said Carl Pelzel, Depomed's president and CEO. “We look forward to discussing further development of DM-1992 with potential collaborative partners,” added Pelzel.

“We are pleased our reformulations of DM-1992 performed as we expected in Parkinson's patients. We believe we have product candidate ready to advance to phase II clinical testing,” said Dr Mike Sweeney, vice president research and development of Depomed. “We would like to thank The Michael J. Fox Foundation for its support in funding a portion of the trial,” added Dr Sweeney.

DM-1992 is an investigative novel gastric-retentive, extended-release dosage form of Levodopa/Carbidopa, a marketed therapy used in the treatment of Parkinson's disease. The phase I trial in DM-1992 was a randomized, open-label crossover study that enrolled 16 patients with stable Parkinson's disease at two leading neurology centres in Russia. The objective of the study was to compare the pharmacokinetics-pharmacodynamics of two distinct twice-daily formulations of DM-1992 and a generic version of Sinemet CR sustained-release Levodopa/Carbidopa dosed three times daily, as well as the safety and tolerability of the formulations.

Patients in the trial received a full day's dose of each of the three treatments being studied (two doses of each DM-1992 (460mg levodopa and 150mg carbidopa per dose) twelve hours apart, and three doses of generic levodopa/carbidopa over a 12 hour period (200mg of levodopa and 50mg of carbidopa per dose). Blood samples were drawn and finger tapping was determined during the 24 hour period following administration of each treatment.

Parkinson's disease is a chronic, degenerative neurological disorder that affects nearly one million Americans, with significant prevalence growth expected over the next 25 years due to aging population demographics. Six million worldwide are estimated to have Parkinson's. While the average age at onset is 60, disease onset starts by age 40 in an estimated five to 10 percent of patients, and people as young as 30 can also be affected.

Current therapies are effective in addressing only the mild/moderate motor symptoms of the disease and have significant long-term side effects. There are no drugs available that target the numerous non-motor aspects of the disease as well as the underlying degenerative process.

The Michael J. Fox Foundation (MJFF) is dedicated to finding a cure for Parkinson's disease through an aggressively funded research agenda and to ensuring the development of improved therapies for those living with Parkinson's today.

Depomed, Inc. is a specialty pharmaceutical company with one approved product on the market and has developed another approved product. Glumetza (metformin hydrochloride extended release tablets) is approved for use in adults with type 2 diabetes and promoted by Santarus, Inc. in the United States. Gralisetm (gabapentin) is a once-daily treatment approved for management of Post-Herpetic Neuralgia (PHN) and has been licensed to Abbott Products, Inc.