On December 13, 2023, Acadia Pharmaceuticals Inc. (Nasdaq: ACAD) announced two significant legal victories that reinforce patent protection for its flagship drug NUPLAZID® (pimavanserin), the only FDA-approved treatment for hallucinations and delusions associated with Parkinson's disease psychosis.
Court Adopts Acadia's Patent Interpretations
The U.S. District Court for the District of Delaware issued a Claim Construction Order ruling in Acadia's favor on all disputed points regarding its '721 formulation patent for NUPLAZID. The court adopted Acadia's interpretation of key disputed terms, which the company believes affirms the strength of the patent that extends protection until 2038.
As a result of this ruling, the previously scheduled claims construction hearing (also known as a "Markman" hearing) set for December 19, 2023, has been canceled. The case remains scheduled for trial in December 2024.
Second Victory Confirms Composition Patent Validity
In a separate litigation on the same day, the Delaware court granted summary judgment to Acadia, confirming the validity of the company's '740 composition of matter patent for NUPLAZID. This patent provides protection until 2030.
The validity challenge came from generic manufacturers who argued that claim 26 of the '740 patent, which covers the tartrate salt of pimavanserin, was invalid due to obvious-type double patenting (OTDP) in relation to Acadia's '271 patent.
The court rejected this argument, interpreting 35 U.S.C. § 121 to provide a "safe harbor" protection against OTDP challenges in this case. The court determined that the '271 patent was filed "as a result of" the original '740 patent, thereby shielding the '740 patent from invalidation.
Comprehensive Patent Protection
"We are pleased to announce a second positive ruling today from the U.S. District Court for the District of Delaware, both of which underscore the strength of our NUPLAZID patent estate, including patents running into 2038," said Steve Davis, President and Chief Executive Officer of Acadia Pharmaceuticals.
Acadia's patent portfolio for NUPLAZID now includes:
- The '721 formulation patent extending to 2038
- A method of use patent for the 10mg tablet extending to 2037
- The '740 composition of matter patent extending to 2030
About NUPLAZID and Its Mechanism
NUPLAZID (pimavanserin) is a selective serotonin inverse agonist and antagonist that preferentially targets 5-HT2A receptors, which are believed to play an important role in neuropsychiatric disorders. The drug demonstrates no appreciable binding affinity for dopamine, histamine, muscarinic, or adrenergic receptors.
The FDA approved NUPLAZID in April 2016 for the treatment of hallucinations and delusions associated with Parkinson's disease psychosis. This approval represented a significant advancement in treating these challenging neuropsychiatric symptoms that affect many Parkinson's disease patients.
Acadia's Pipeline and Focus
Beyond NUPLAZID's current indication, Acadia is developing pimavanserin as a potential treatment for the negative symptoms of schizophrenia. The company's broader clinical-stage development efforts focus on treating negative symptoms of schizophrenia, Prader-Willi syndrome, Alzheimer's disease psychosis, and neuropsychiatric symptoms in central nervous system disorders.
With 30 years of experience in neuroscience, Acadia continues to work at the forefront of healthcare to bring vital solutions to patients with significant unmet needs. The company has established itself as a leader in developing treatments for neuropsychiatric conditions, having commercialized therapies for both Parkinson's disease psychosis and Rett syndrome.
Implications for Patients and Market
These patent victories are significant for patients who rely on NUPLAZID, as they help ensure continued availability of the branded medication without generic competition for many years. For Acadia, the rulings protect a key revenue source and validate the company's intellectual property strategy.
The establishment of claims construction is considered an important milestone in patent litigation. With these favorable rulings, Acadia is well-positioned to proceed with the remainder of its formulation patent case and maintain market exclusivity for NUPLAZID through the end of the 2030s.
