FDA Approves Extended Release Levodopa-Carbidopa

Today MJFF-awardee Impax Pharmaceuticals announced that the U.S. Food and Drug Administration approved RYTARY, an extended-release oral capsule formulation of levodopa-carbidopa, for the treatment of Parkinson’s disease.

“The FDA approval of RYTARY (pronounced rye-TAR-ee) is an important new development for the treatment of Parkinson’s disease,” said Fred Wilkinson, president and CEO, Impax Laboratories. “RYTARY is designed to address one of the most significant unmet needs for patients living with Parkinson’s disease, which is to reduce the amount of time during the day when their symptoms are not adequately controlled.”

Participants in a Phase III clinical trial experienced nearly an hour and a half less “off time” per day when taking the drug, as compared with carbidopa-levodopa plus entacapone, another drug to lengthen efficacy of levodopa.

Levodopa better than any drug.

Whether to begin Parkinson’s treatment with the gold-standard levodopa or other therapy (e.g., dopamine agonist, MAO-B inhibitor) is a question debated among neurologists and patients.

A paper published today in The Lancet reports that early treatment of levodopa provides better mobility and quality of life after seven years over early treatment with dopamine agonists or MAO-B inhibitors. In the largest-ever Parkinson’s disease trial — called PD MED — a group of researchers from 80 sites throughout the United Kingdom and led by Dr. Richard Gray of the University of Oxford compared the three therapies in a total of 1,620 newly diagnosed patients, including those with young onset PD.

In a comment also published by The Lancet, Drs. Anthony Lang and Connie Marras (both from the University of Toronto) wrote, “The results of this study will help to persuade physicians and reassure patients that the fears that have served as the groundwork in establishing levodopa phobia — that often results in patients experiencing unnecessary and easily managed disability and reduction in quality of life in the early years of their disease — are unfounded.”

Some physicians are reluctant to begin patients on levodopa due to the earlier onset of levodopa-induced dyskinesia — a side effect of the medication that presents with jerky, fractured movements — and motor fluctuations or “off” episodes.

The PD MED study asked patients to complete a questionnaire on their quality of life relative to their mobility. After three years, patients on levodopa averaged 1.8 points better than patients on dopamine agonists or MAO-B inhibitors, and that beneficial difference remained seven years into the trial.

Dr. Gray was quoted saying, “Although the differences in favor of levodopa are small, when you consider the short- and long-term benefits, side-effects, quality of life for patients, and costs, the old drug levodopa is still the best initial treatment strategy for most patients.”