In his latest blog for the Journal of Parkinson’s Disease, journalist and Parkinson's patient Jon Palfreman highlights a new article which reflects on the longstanding efforts to improve upon levodopa, still the gold standard therapy for PD more than 40 years after it was first prescribed to treat the symptoms of the disease. Despite a significant push in the field to better treat PD with levodopa while minimizing side effects such as dyskinesia, so far “all this effort has only delivered incremental improvements.”
The major question Palfreman addresses in his blog: When should a patient begin levodopa therapy? Neurologists are still divided on the question, he writes:
The Parkinson’s Institute’s Bill Langston urges caution. 'Once you are on levodopa, you start the clock; once the basal ganglia is sensitized there’s no going back. So save your ammo as long as you comfortably can.' Susie Ro of the Seattle-based Swedish Medical Center disagrees. 'There is no convincing evidence that saving levodopa until the last possible minute does anything but delay and thereby lessen the time when a person could be having their best level of function.'
(Palfreman examines three factors that scientists are currently at work to solve the riddle: the disease itself, the “kinetics” of the drug, and the potential long-term effects on of the drug on an area of the brain called the basal ganglia. Read the blog to learn more).
Palfreman also acknowledges that, should scientists find a way to more consistently deliver levodopa throughout the body, the question as to when a patient begins the therapy could become moot.
So far, this has not been an easy question to answer. But the good news is The Michael J. Fox Foundation (MJFF) is supporting promising research to this end. Several projects to pay attention to include:
- An inhaled formulation of levodopa from Civitas Therapeutics which is currently in the second phase of clinical testing.
- A levodopa/carbidopa “pump patch” from Israeli drugmaker Neuroderm that the Foundation will support for a planned Phase 2 trial.
- An improved pill formulation called an “accordion pill” from Intec Pharmaceuticals.
In addition, in 2012 AbbVie announced positive Phase 3 results into a levodopa-carbidopa intestinal gel (LCIG) that is delivered into a patient’s small intestines with a small pump. This product is currently available in Europe under the brand name duodopa.