Pasithea Therapeutics Announces Grant of Fast Track Designation by FDA to PAS-004 for Treatment of Neurofibromatosis Type 1 (NF1) Associated Plexiform Neurofibromas (PN) Causing Significant Morbidity
Rhea-AI Summary
Pasithea Therapeutics (NASDAQ: KTTA) announced the FDA granted Fast Track designation to PAS-004 for treatment of NF1-associated plexiform neurofibromas (PN) causing significant morbidity on April 1, 2026. The designation enables frequent FDA communications and rolling review and may allow accelerated approval or priority review if criteria are met. The company is conducting a Phase 1/1b dose-escalation trial (NCT06961565).
Positive
- Fast Track designation granted by FDA for PAS-004
- Rolling review eligibility enabling earlier submission review
- Frequent FDA interactions to facilitate development
- Ongoing Phase 1/1b multicenter dose-escalation trial (NCT06961565)
Negative
- PAS-004 remains in early-stage Phase 1/1b testing with no regulatory approval
- Fast Track does not guarantee approval or successful clinical outcome
News Market Reaction – KTTAW
In the Apr 1 session, KTTAW declined 53.98%, reflecting a significant negative market reaction.
Data tracked by StockTitan Argus on the day of publication.
Key Figures
Previous Clinical trial Reports
| Date | Event | Sentiment | 24h Move | Catalyst |
|---|---|---|---|---|
| Nov 24 | Phase 1 cohort data | Positive | +7.3% | Completion of Cohort 7 with favorable safety, PK and PD data. |
| Nov 21 | PK data update | Positive | -1.6% | Positive tablet PK data showing linear, dose‑proportional exposure. |
| Nov 20 | Interim efficacy data | Positive | -1.6% | Positive Phase 1 data with partial response and 71.4% disease control rate. |
| Nov 04 | New trial site U.S. | Positive | +61.8% | Activation of UAB clinical site for NF1 Phase 1/1b PAS-004 trial. |
| Sep 16 | New trial sites Korea | Positive | -0.7% | Activation of two South Korea sites for NF1 Phase 1/1b study. |
24h Move is the share-price change in the day after each event; other market factors may also have contributed.
Clinical PAS-004 updates often had positive fundamentals but produced mixed, sometimes divergent, price reactions.
Over recent months, Pasithea’s PAS-004 program advanced through multiple Phase 1/1b milestones, including South Korea site activations on Sep 16, 2025, UAB site activation on Nov 4, 2025, and positive PK and safety data updates in November 2025. Price reactions to these clinical trial announcements ranged from modest gains to declines, despite generally constructive data. Today’s Fast Track designation for NF1-associated PN fits this sequence of regulatory and clinical progress for PAS-004.
Key Terms
fast track designation regulatory
mek inhibitor medical
phase 1/1b medical
open-label medical
dose escalation medical
AI-generated analysis. How Rhea-AI works. Not financial advice.
Fast Track designation is one of the FDA’s expedited programs meant to facilitate development and expedite review of new drugs that have the potential to address an unmet medical need in the treatment of a serious or life-threatening condition
MIAMI, April 01, 2026 (GLOBE NEWSWIRE) -- Pasithea Therapeutics Corp. (NASDAQ: KTTA) (“Pasithea” or the “Company”), a clinical-stage biotechnology company developing PAS-004, a next-generation macrocyclic MEK inhibitor, today announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to PAS-004 for the treatment of NF1-associated PN causing significant morbidity.
"We appreciate the FDA’s decision that PAS-004 meets the criteria for Fast Track designation for this indication,” said Dr. Tiago Reis Marques, Chief Executive Officer of Pasithea. “The ability to have early and frequent interactions with the FDA supports our goal to expeditiously develop PAS-004 for patients with NF1-associated PN causing significant morbidity.”
Fast Track designation includes the following opportunities to facilitate Fast Track product development:
- Frequent communications with the FDA review team throughout the product development process
- Rolling Review, which allows portions of a marketing application to be reviewed and assessed by the FDA before the company submits the complete application
- In addition, a Fast Track designation product may potentially be eligible for accelerated approval and/or priority review if relevant criteria are met. For more information, see the FDA’s website at
https://www.fda.gov/patients/fast-track-breakthrough-therapy-accelerated-approval-priority-review/fast-track
The Company is currently conducting a Phase 1/1b multicenter, open-label, dose escalation trial of PAS-004 in adult participants with symptomatic, inoperable, incompletely resected, or recurrent NF1-PN (NCT06961565).
About NF1- PN
Plexiform neurofibromas (PN) are tumors originating from the nerve sheath that grow through and around nerves and may involve multiple nerve branches. Thirty to fifty percent (30
About Pasithea Therapeutics Corp.
Pasithea is a clinical-stage biotechnology company primarily focused on the research and development of its lead drug candidate, PAS-004, a next-generation macrocyclic MEK inhibitor intended for the treatment of RASopathies, MAPK pathway-driven tumors, and other diseases. The Company is currently testing PAS-004 in a Phase 1 clinical trial in patients with advanced cancer (NCT06299839), and a Phase 1/1b clinical trial in patients with neurofibromatosis type 1 (NF1)-associated plexiform neurofibromas with symptomatic and inoperable, incompletely resected, or recurrent PN (NCT06961565).
Forward Looking Statements
This press release contains statements that constitute “forward-looking statements” made pursuant to the safe harbor provisions of the Private Securities Litigation Reform Act of 1995. These forward-looking statements include statements regarding the Company’s ongoing Phase 1 clinical trial of PAS-004 in advanced cancer patients, the Company’s ongoing Phase 1/1b clinical trial of PAS-004 in adult NF1 patients, and the safety, tolerability, pharmacokinetic (PK), pharmacodynamics (PD) and preliminary efficacy of PAS-004, as well as all other statements, other than statements of historical fact, regarding the Company’s current views and assumptions with respect to future events regarding its business, as well as other statements with respect to the Company’s plans, assumptions, expectations, beliefs and objectives, the success of the Company’s current and future business strategies, product development, pre-clinical studies, clinical studies, clinical and regulatory timelines, market opportunity, competitive position, business strategies, potential growth and financing opportunities and other statements that are predictive in nature. Forward-looking statements are subject to numerous conditions, many of which are beyond the control of the Company. While the Company believes these forward-looking statements are reasonable, undue reliance should not be placed on any such forward-looking statements, which are based on information available to the Company on the date of this release. These forward-looking statements are based upon current estimates and assumptions and are subject to various risks and uncertainties, including risks that future clinical trial results may not match results observed to date, may be negative or ambiguous, or may not reach the level of statistical significance required for regulatory approval, as well as other factors set forth in the Company’s most recent Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and other filings made with the U.S. Securities and Exchange Commission (SEC). Thus, actual results could be materially different. The Company undertakes no obligation to update these statements, whether as a result of new information, future events, or otherwise, after the date of this release, except as required by law.
Pasithea Therapeutics Contact
Patrick Gaynes
Investor Relations
pgaynes@pasithea.com
