A federal judge has ruled in favor of Acadia Pharmaceuticals Inc. in a patent dispute against Aurobindo Pharma Ltd., protecting Acadia's Parkinson's disease psychosis drug Nuplazid (pimavanserin) from generic competition until 2038.
In an order issued on May 16, 2025, Judge Gregory B. Williams of the U.S. District Court for the District of Delaware determined that Aurobindo's proposed generic pimavanserin capsules would infringe U.S. Patent No. 11,452,721 held by Acadia. The court rejected Aurobindo's arguments challenging the patent's validity.
"We are very pleased with today's decisive ruling in our favor, which provides patent protection for NUPLAZID 34 mg capsule formulation into 2038," said Catherine Owen Adams, Chief Executive Officer of Acadia. "This result highlights Acadia's dedication to safeguarding our advancements in therapies for conditions with significant unmet medical needs."
Patent Protection Extends Market Exclusivity
The ruling follows a December bench trial and secures Acadia's market exclusivity for Nuplazid capsules for more than 13 additional years. The '721 formulation patent and three related patents are set to expire in August 2038, representing the latest expiration dates in Acadia's patent portfolio for the drug.
Aurobindo had filed an Abbreviated New Drug Application (ANDA) seeking approval to market generic versions of Nuplazid before the expiration of Acadia's patents. The court's decision prevents Aurobindo and other ANDA filers from launching generic versions of the drug until the patent expires, barring any successful appeals.
Significance for Parkinson's Disease Patients
Nuplazid is the first and only FDA-approved drug specifically designed to treat hallucinations and delusions associated with Parkinson's disease psychosis, a condition that affects a significant portion of the approximately one million Americans living with Parkinson's disease.
Parkinson's disease psychosis can significantly impact patients' quality of life and often leads to increased caregiver burden and higher rates of institutionalization. By maintaining market exclusivity, Acadia ensures continued access to this specialized treatment while potentially funding further research and development in neuroscience.
Acadia's Broader Neuroscience Portfolio
Beyond Nuplazid, Acadia has established itself as a leader in neuroscience research. The company also developed and commercialized the first and only approved drug in the United States and Canada for the treatment of Rett syndrome, a rare genetic neurological disorder.
Acadia's clinical-stage development pipeline includes programs targeting Prader-Willi syndrome and Alzheimer's disease psychosis, among other neuroscience and neuro-rare disease indications. The patent victory for Nuplazid strengthens the company's position as it continues to advance treatments for conditions with significant unmet medical needs.
Implications for Pharmaceutical Patent Litigation
This case highlights the ongoing tension between brand-name pharmaceutical companies seeking to protect their intellectual property and generic manufacturers attempting to bring lower-cost alternatives to market. Patent litigation remains a critical strategy for innovative drug developers to maintain market exclusivity beyond basic compound patents.
The sealed opinion explaining Judge Williams' reasoning may provide important precedent for future pharmaceutical patent cases, particularly those involving formulation patents, which protect specific drug delivery methods rather than the active pharmaceutical ingredient itself.
For Acadia, the ruling represents a significant win that protects a key revenue source while the company continues to develop its pipeline of neuroscience therapies.
