Acorda Therapeutics, Inc. announced that the United States Patent and Trademark Office (USPTO) has allowed US Patent Application No. 11/102,559 entitled “Method of Using Sustained Release Aminopyridine Compositions.” The claims of the patent application relate to methods to improve walking, walking speed, lower extremity muscle tone and lower extremity muscle strength in patients with multiple sclerosis (MS) by administering 10 mg of sustained release 4-aminopyridine (dalfampridine) twice daily. This patent application is separate from the Ampyra method of use patent application which was allowed by the USPTO in April 2011.

“The allowance of this patent application further strengthens our patent protection for Ampyra and enhances our ability to continue exploring potential new uses and indications, both in MS and other diseases,” said Ron Cohen, MD, president and CEO of Acorda Therapeutics. “The discoveries we made during our development of Ampyra, several of which are reflected in this patent, were critical to receiving US FDA approval and making this therapy available to people with MS who have walking impairment. We are pleased that the UPTO has recognized these findings as innovative and valuable contributions to medicine.”

The patent issuing from Application No. 11/102,559 is currently set to expire in April 2025, but is also eligible for patent term adjustment, to be determined by the USPTO based on the prosecution history. This patent is eligible for listing in the US Food and Drug Administration (US FDA) Orange Book.

Sustained release 4-aminopyridine is marketed in the United States under the trade name Ampyra (dalfampridine) Extended Release Tablets, 10 mg. Ampyra is an oral medication approved by the FDA as a treatment to improve walking in patients with multiple sclerosis (MS). This was demonstrated by an increase in walking speed. It can cause seizures; the risk of seizures increases with increasing AMPYRA doses. It is contraindicated in patients with a prior history of seizure. Discontinue the use if seizure occurs.

Ampyra is contraindicated in patients with moderate or severe renal impairment (CrClless-than or equal to 50 mL/min); the risk of seizures in patients with mild renal impairment (CrCl 51-80 mL/min) is unknown, but Ampyra plasma levels in these patients may approach those seen at a dose of 15 mg twice daily, a dose that may be associated with an increased risk of seizures; estimated CrCl should be known before initiating treatment with Ampyra.

It should not be taken with other forms of 4-aminopyridine (4-AP, fampridine), since the active ingredient is the same. Urinary tract infections were reported more frequently as adverse reactions in patients receiving Ampyra 10 mg twice daily compared to placebo.

The most common adverse events (incidence greater-than or equal to 2% and at a rate greater than the placebo rate) for Ampyra in MS patients were urinary tract infection, insomnia, dizziness, headache, nausea, asthenia, back pain, balance disorder, multiple sclerosis relapse, paresthesia, nasopharyngitis, constipation, dyspepsia, and pharyngolaryngeal pain.

Ampyra is a potassium channel blocker approved as a treatment to improve walking in patients with multiple sclerosis (MS). This was demonstrated by an increase in walking speed. Ampyra, which was previously referred to as Fampridine-SR, is an extended release tablet formulation of dalfampridine (4-aminopyridine, 4-AP), which was previously called fampridine, and remains known by that name outside the US. In laboratory studies, dalfampridine has been found to improve impulse conduction in nerve fibers in which the insulating layer, called myelin, has been damaged. It is being developed and commercialized in the United States by Acorda Therapeutics, and by Biogen Idec in markets outside the US based on a licensing agreement with Acorda. Ampyra is manufactured globally by Elan based on a supply agreement with Acorda.