ProMIS Neurosciences Inc. (NASDAQ:PMN) reported positive blinded six-month interim safety and biomarker results from its ongoing Phase 1b PRECISE-AD trial evaluating lead drug candidate PMN310 in patients with mild cognitive impairment due to Alzheimer’s disease.

The clinical-stage biopharmaceutical company develops therapies targeting toxic misfolded proteins linked to neurodegenerative diseases.

Favorable Safety Profile Across Genotypes

The blinded interim analysis included 136 Alzheimer’s disease patients and showed a favorable safety profile across all genotypes.

No cases of amyloid-related imaging abnormalities with edema (ARIA-E) were reported as of the data cutoff date. Total ARIA incidence was 4.4%, with all cases limited to mild, asymptomatic amyloid-related imaging abnormalities-microhemorrhages (ARIA-H).

The company also reported no treatment-related serious adverse events and no drug-related patient discontinuations.

Safety Maintained In High-Risk APOE4 Patients

The favorable safety profile was also observed among high-risk APOE4 carriers, who represented 61% of the trial population, including 11% who were homozygotes.

ProMIS noted that this patient group remains underserved by many currently approved amyloid-targeting therapies.

Early Biomarker Movement And Differentiated Mechanism

On a blinded basis, 68.5% of patients exhibited a decline from baseline in plasma pTau217, and 62.5% showed a decline in CSF MTBR-tau243, contrasting with expected natural-history increases.

These trends potentially reflect the trial’s 3:1 active-to-placebo randomization.

However, because treatment allocations remain blinded, these observations do not constitute a determination of clinical efficacy.

PMN310 utilizes a differentiated, oligomer-selective mechanism engineered to selectively bind toxic amyloid-beta oligomers while avoiding plaque, aiming to decouple potential efficacy from ARIA risk.

The trial remains ongoing, with unblinded 12-month topline results, including efficacy data, expected in the first quarter of 2027.

By selectively targeting toxic oligomers, PMN310 “has the potential to deliver the benefits of amyloid-directed therapy without the ARIA burden that has constrained this class of drugs,” said Neil Warma, CEO of ProMIS Neurosciences.

“The absence of ARIA-E, an overall favorable safety profile, and early biomarker movement together align with our expectations based on our prior studies,” Warma added.

PMN Stock Price Activity: ProMIS Neurosciences shares were up 18.67% at $13.90 at the time of publication on Tuesday, according to Benzinga Pro data.

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