FDA grants orphan status to Pasithea’s ALS therapy candidate

Pasithea Therapeutics (NASDAQ:KTTA) announced that the U.S. Food and Drug Administration has granted Orphan Drug Designation to its lead therapeutic candidate, PAS-004, for the treatment of Amyotrophic Lateral Sclerosis (ALS).

The designation is intended to support the development of therapies targeting rare diseases or conditions affecting fewer than 200,000 people in the United States.

Under the orphan status framework, the clinical-stage biotechnology company becomes eligible for multiple financial and regulatory development incentives.

These include tax credits for qualified clinical trials, exemptions from certain FDA user fees, and the potential for seven years of market exclusivity within the U.S. market following official regulatory approval.

PAS-004 is a next-generation macrocyclic mitogen-activated protein kinase kinase (MEK) inhibitor.

The molecule is designed to address neurodegenerative pathologies where dysregulation of the mitogen-activated protein kinase (MAPK) pathway is believed to play an active role.

ALS is a progressive and universally fatal neurodegenerative disease that targets nerve cells in the brain and spinal cord, causing patients to lose functional control over movement, speech, and respiration, typically within five years of diagnosis.

The regulatory milestone follows prior non-dilutive funding from patient advocacy groups.

In November 2025, Pasithea secured a $1 million grant award from the ALS Association to fund the evaluation of the compound's efficacy, safety, and tolerability in ALS models.

Beyond its neurodegenerative pipeline, the company is currently evaluating PAS-004 across separate clinical pathways.

The molecule is undergoing testing in an open-label Phase 1 clinical trial for patients with advanced solid tumors, alongside a Phase 1/1b study targeting neurofibromatosis type 1-associated plexiform neurofibromas.