EXCLUSIVE: MIRA Pharmaceuticals Lead Program Ketamir-2 Shows No Brain Toxicity In FDA-Mandated Study

MIRA Pharmaceuticals, Inc. MIRA released results from a neurotoxicity study of Ketamir-2, its novel oral NMDA receptor antagonist, on Tuesday.

The U.S. Food and Drug Administration (FDA) required the study before initiating human dosing in the United States.

The preclinical study showed no evidence of brain toxicity, including the absence of Olney lesions—vacuolar brain changes historically associated with older NMDA-targeting drugs such as ketamine and MK-801.

These results further confirm the favorable safety profile of Ketamir-2 and support its safe continued clinical development.

Also Read: EXCLUSIVE: MIRA Pharmaceuticals Expands Pipeline, Enhances Value Proposition With Development Of Topical Formulation For Lead Pain Treatment Candidate

Study Overview

• The neurotoxicity study was conducted in sexually mature Sprague-Dawley rats.
• High oral doses of Ketamir-2 were administered, while a positive control group received MK-801, a known neurotoxic NMDA receptor antagonist. Brain tissues were examined through detailed histopathological analysis at two-time points.

Key outcomes:

• No adverse clinical signs or mortality in any Ketamir-2-treated animals.
• No microscopic or macroscopic brain lesions were detected at any dose.
• MK-801-treated animals showed clear evidence of brain toxicity, including vacuolation and neuronal necrosis.

In prior preclinical studies, Ketamir-2 has:

• Demonstrated full reversal of pain thresholds in validated neuropathic pain models.
• Outperformed FDA-approved treatments such as gabapentin and pregabalin.
• Showed no sedation or hyperactivity.
• Demonstrated strong oral bioavailability and brain penetration, as it is not a substrate for P-glycoprotein (P-gp).

Ketamir-2 was designed for oral administration, offering a non-invasive alternative to intravenous therapies.

In addition, the U.S. Drug Enforcement Administration has determined that Ketamir-2 is not classified as a controlled substance, which may streamline development, reduce regulatory burdens, and improve future access if approved.

MIRA has initiated its Phase 1 clinical trial, with subject recruitment actively underway.

The company is preparing to launch a Phase 2a proof-of-concept trial in diabetic patients with neuropathic pain to validate clinical efficacy and support future regulatory milestones.

The results of the newly completed neurotoxicity study will be submitted to the FDA as part of MIRA's ongoing regulatory and clinical development strategy.

In April, MIRA Pharmaceuticals released data demonstrating the efficacy of the oral ketamine analog, Ketamir-2, in a validated animal model of diabetic neuropathy, a type of nerve damage that can occur in diabetes patients. 

Price Action: MIRA stock is up 2.56% at $1.20 during the premarket session at the last check Tuesday.