Possible Parkinson’s Treatment for Levodopa-Induced Dyskinesia Gets US Patent Protection

Amarantus BioScience Holdings, Inc. (AMBS) received a Notice of Allowance from the U.S. Patent and Trademark Office covering the use of 5HT1A in combination with 5HT1B agonists, including the clinical Phase 2b stage drug eltoprazine, to treat levodopa-induced dyskinesia (PD-LID) in Parkinson’s disease (PD). The office issues such a notice after determining that a patent should be issued based on examination of the filing.

This Notice of Allowance was received for a patent application filed as a continuation, in part, to a previously issued patent (No. 9,066,903), and reinforces Amarantus’ intellectual property protection for the potential combination 5HT1A/1B receptor agonist against competitors also targeting PD-LID. For eltoprazine, the notice provides further protection through 2027.

Eltoprazine is a small molecule in clinical development for the treatment of levodopa-induced dyskinesia in Parkinson’s patients and for adult attention deficit hyperactivity disorder (ADHD). Patient enrollment for the current Phase 2b trial is momentarily stopped, as Amarantus expects a decision from the U.S. Department of Food and Drug Administration (FDA) regarding an orphan drug application submitted for PD-LID that may change the company’s development plan.

Levodopa-induced dyskinesia, a form of dyskinesia associated with the drug levodopa used to treat PD, often involves hyperkinetic movements, including chorea, dystonia, and athetosis. In the context of PD, dyskinesia is often the result of chronic L-DOPA (levodopa) therapy. These motor fluctuations occur in more than half of PD patients after 5–10 years of L-DOPA treatment, with the percentage of affected patients increasing over time.

“This Notice of Allowance for eltoprazine in Parkinson’s disease levodopa-induced dyskinesia significantly strengthens the company’s intellectual property position by creating an additional barrier to entry for the 5HT1A/1B receptor agonist field for the treatment of PD-LID,” said Gerald E. Commissiong, president and CEO of Amarantus, in a recent press release. “As we await a decision from the US FDA on the orphan drug designation for treating PD-LID, we are currently evaluating alternative clinical pathways by which to accelerate our commercialization timeline, while also evaluating strategic interest in the overall eltoprazine program which includes Alzheimer’s aggression and adult ADHD.”

To date, eltoprazine has been assessed in more than 680 patients, and has a known safety profile. The drug initially entered clinical development at Solvay Pharmaceuticals to treat aggression, but the clinical program was out-licensed to PsychoGenics when Solvay merged with Abbott Pharmaceuticals. Eltroprazine was then licenced to Amarantus after positive proof-of-concept clinical trials in PD-LID as well as in adult ADHD.