As the incidence of Parkinson’s grows—an estimated 50,000 new cases per year—so do the options being offered by drug manufacturers. 

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Today’s Parkinson’s treatment options address the symptoms of tremors, stiffness, and slow movement to improve quality of life. However, they do little to slow the progression of this disease.  Fortunately, research is helping us better understand Parkinson’s. While early signs of Parkinson’s disease can be overlooked, once it’s diagnosed, treatment options are expanding beyond the current drugs. So one day we may find a Parkinson’s treatment that makes the disease less of a life sentence.

“If you have Parkinson’s disease, there aren’t any treatments that can slow, reverse, or stop the condition’s progression,” says Kara J. Wyant, M.D., in a Michigan Health blog on Parkinson’s treatment. “But, although there is no cure, more than a dozen medications can help patients manage symptoms. Our goals when prescribing medications for Parkinson’s disease are twofold: to improve day-to-day functioning and quality of life and to keep people functioning as long as possible.”

Recent FDA Approvals

As the incidence of Parkinson’s grows—an estimated 50,000 new cases per year—so do the options being offered by drug manufacturers. Among the most recently approved options are:

Once-daily Osmolex: In February 2018, the FDA approved Osmotica Pharmaceutical’s Osmolex ER. This is amantadine in an extended-release tablet, which is a Parkinson’s treatment and for drug-induced movement disorders. Osmolex ER uses technology that allows both an immediate release and an extended release of the amantadine.

Deep-brain stimulation implant: In December 2017, the FDA approved Boston Scientific’s Vercise DBS System, an implanted neurostimulator that generates an electrical pulse that is delivered to the brain as a Parkinson’s treatment. The FDA says the Vercise DBS System is used as an adjunctive therapy in reducing some of the symptoms of moderate-to-advanced levodopa-responsive Parkinson’s disease that is not adequately controlled with medication. Medscape Medical News says the implant has been available in Europe since 2012.

Transdermal patch: In May 2017, Schwarz Pharma’s Neupro received FDA approval for early-stage Parkinson’s treatment. The active ingredient is rotigotine, which mimics the action of dopamine for proper motor functioning. The patch is applied to the skin once daily and provides rotigotine continuously for 24 hours.

Off-time drug: In March 2017, the FDA approved Newron Pharmaceutical’s Xadago (safinamide) tablets as an add-on Parkinson’s treatment for patients taking levodopa/carbidopa and experiencing “off” times when the medications aren’t working well and symptoms increase. Xadago is an add-on therapy to be used with levodopa.

New drug application: The U.S. Food & Drug Administration has accepted a New Drug Application for Acorda Therapeutic’s Inbrija, which is an inhaled levodopa treatment for symptoms during “off” periods in those on a carbidopa/levodopa regimen. A New Drug Application means a company has submitted its research to the FDA, requesting the drug is approved. Acorda hopes for an October 2018 approval.

Parkinson’s Treatment on the Horizon

Immunotherapy:  Researchers at the Columbia University Medical Center and the La Jolla Institute for Allergy and Immunology have found evidence that autoimmunity—in which the immune system attacks the body’s own tissues—plays a role in Parkinson’s disease. The findings raise the possibility that the death of neurons in Parkinson’s could be prevented by therapies that dampen the immune response.

“Our findings raise the possibility that an immunotherapy approach could be used to increase the immune system’s tolerance for alpha-synuclein, which could help to ameliorate or prevent worsening symptoms in Parkinson’s disease patients,” says study co-leader Alessandro Sette, Dr. Biol. Sci., professor in the Center for Infectious Disease at La Jolla Institute for Allergy and Immunology in La Jolla, Calif. The study was published in Nature.

“The idea that a malfunctioning immune system contributes to Parkinson’s dates back almost 100 years,” said study co-leader David Sulzer, PhD, professor of neurobiology at CUMC. “But until now, no one has been able to connect the dots. Our findings show that two fragments of alpha-synuclein, a protein that accumulates in the brain cells of people with Parkinson’s, can activate the T cells involved in autoimmune attacks.”

Antioxidants: A study published in Science showed that intervening with an antioxidant early in the Parkinson’s disease process may break the degenerative cycle and improve neuron function. Northwestern Medicine scientists identified a toxic cascade that leads to neuronal degeneration in patients with Parkinson’s disease and figured out how to interrupt it. The scientists also discovered that mouse models of Parkinson’s disease didn’t have the same abnormalities they found in human Parkinson’s neurons, revealing the importance of studying human neurons to develop new therapies.

“One of the key strategies that worked in our experiments is to treat dopamine neurons early in the toxic cascade with specific antioxidants that improve mitochondrial oxidant stress and lower oxidized dopamine,” says Dr. Dimitri Krainc, the Aaron Montgomery Ward Professor and chair of neurology at Northwestern University Feinberg School of Medicine.

Doxycycline: A study published in Scientific Reports suggests that doxycycline, an antibiotic used for over half a century against bacterial infections like Lyme disease, can be prescribed at lower doses for Parkinson’s treatment.  The discovery was made during an unrelated study on Parkinson’s treatment: A lab technician accidentally fed that study’s mice a feed laced with doxycycline. Only two of the 40 mice developed Parkinson’s disease.

“We haven’t published any data yet, but I can say right away that doxycycline improves the symptoms of the disease in the animal model,” says Elaine Del-Bel, affiliated with the University of São Paulo’s Ribeirão Preto Dental School. “Preliminary results suggest that besides its anti-inflammatory action via a reduction in the release of some cytokines, doxycycline also alters the expression of key genes for the development of Parkinson’s.”

Diabetic drug: A drug used to treat diabetes may have disease-modifying potential to treat Parkinson’s disease. The study, published in The Lancet and funded by The Michael J. Fox Foundation, found that people with Parkinson’s who injected themselves each week with exenatide (Bydureon, Byetta) for one year performed better in movement tests than those who injected a placebo.

“This is the strongest evidence we have so far that a drug could do more than provide symptom relief for Parkinson’s disease,” says the study’s senior author, Professor Tom Foltynie (UCL Institute of Neurology).

D-512 Parkinson’s treatment:  Researchers at the State University of New York Binghamton University have developed a new drug that may limit the progression of Parkinson’s and provide better symptom relief.

Psychology professor Chris Bishop and former graduate student David Lindenbach employed a preclinical model of Parkinson’s disease to compare the effects of the dopamine agonist ropinirole to their new drug, D-512. Results demonstrated that D-512 was more efficacious than ropinirole in treating symptoms, while also prolonging the time window in which the animals showed benefits. These findings followed on the heels of prior work by this collaborative group which demonstrated that D-512 may also protect again the progression of Parkinson’s disease.

“A major issue for Parkinson’s disease patients is the need to take multiple medications, multiple times per day. So, we were quite astounded to discover that our new compound, D-512, was superior to the widely-used drug, ropinirole, in terms of maximal symptom relief and duration of action,” says Lindenbach.

“D-512 is unique because it not only treats the symptoms of Parkinson’s disease, but the molecule itself is an antioxidant,” says Lindenbach. “This antioxidant property is important because a major cause of Parkinson’s disease appears to be excessive oxidative stress is a small group of movement-facilitating brain cells.”