There is hope that the drug rasagiline can do what no other medication for Parkinson's disease now does -- slow the progression of a devastating degenerative brain disease that eventually robs people of their ability to move and function.
Now a new study looking at the long-term effects of rasagiline (Azilect) on newly diagnosed patients indicates that people who began the drug earlier continued to do better than those for whom treatment was delayed six months. The study "Long-term Outcome of Early Versus Delayed Rasagiline Treatment in Early Parkinson's Disease" was recently published in the early online version of the journal Movement Disorders .
"Patients who received rasagiline right from the beginning rather than after a six-month delay experienced less progression of the clinical signs and symptoms of Parkinson's disease that interfere with activities of daily living such as eating, walking and dressing," said the study's lead author Robert A. Hauser, MD, director of the University of South Florida Parkinson's Disease and Movement Disorders Center. "This is potentially consistent with a slowing of underlying disease progression, although other possible mechanisms also need to be considered."
The study, sponsored by Teva Pharmaceutical Industries Ltd. (Israel), Teva Neuroscience, Inc. (USA) and H. Lundbeck A/S (Denmark), was a long-term open label extension of the multisite trial "TVP-1012 (rasagiline) in Early Monotherapy for Parkinson's Disease Outpatients" study, known as TEMPO. In TEMPO, more than 400 untreated patients with early Parkinson's disease were randomly assigned to rasagiline for a year (1 mg daily or 2 mg daily) or to placebo for six months followed by rasagiline for six months (2 mg daily). At the end of a year, patients receiving rasagiline from the start fared better as measured by the Unified Parkinson's Disease Rating Scale. They experienced less worsening of motor symptoms, such as rigidity and tremor, and had fewer problems with activities of daily living than patients who began rasagiline six months later.
The open-label extension study followed more than 300 patients from the TEMPO study for up to 6.5 years. In this extension study, all patients continued on rasagiline (1 mg. daily) and could take other Parkinson's disease medications as needed. The researchers found those who started rasagiline right from the beginning of the TEMPO study continued to fare better than patients in the delayed-start group. Over the course of the entire study, the early-start group had 16 percent less progression of the signs and symptoms of Parkinson's disease, and this greater clinical benefit was observed even as patients received conventional Parkinson's disease medications in addition to rasagiline. Rasagiline appeared to be well tolerated in this long-term study.
If the clinical outcomes from the TEMPO and extension study hold up under further scrutiny, it may indicate that early initiation of rasagiline confers a protective effect against disease progression, Dr. Hauser said. "If this is the case, it reinforces the importance of individuals being diagnosed and treated as soon as possible."
The study authors point out that early initiation of any drug to relieve symptoms of Parkinson's disease may lead to a better clinical outcome compared to delayed administration -- something that will be elucidated as more delayed-start studies are performed with other Parkinson's medications.