ProMIS Neurosciences Announces Positive Phase 1a Alzheimer's Trial Results

ProMIS Neurosciences, Inc., a biotechnology company based in Cambridge, Massachusetts and Toronto, Ontario, has announced promising top-line results from its first-in-human Phase 1a clinical trial of the antibody therapeutic PMN310. PMN310 targets toxic misfolded proteins associated with neurodegenerative diseases like Alzheimer’s disease (AD), amyotrophic lateral sclerosis (ALS), and multiple system atrophy (MSA). The trial’s initial data reveals that PMN310 is safe, well-tolerated, and effectively crosses the blood-brain barrier in healthy volunteers.

The Phase 1a trial involved five single-ascending dose (SAD) cohorts, with the first four cohorts receiving doses of 2.5, 5, 10, and 20 mg/kg. The participants were closely monitored, and no serious adverse events were reported. The cerebrospinal fluid (CSF) collected on days 3 and 29 after administration showed dose-dependent levels of PMN310, indicating its potential for effective target engagement in AD patients. The half-life of PMN310 in the CSF was approximately 25 days, which could allow for once-a-month dosing.

Neil Warma, CEO of ProMIS Neurosciences, emphasized the significance of these findings for the Alzheimer's community. He noted that PMN310 could become a transformative treatment option for early Alzheimer’s disease by selectively targeting toxic soluble amyloid-beta oligomers (AbO), which are believed to be crucial in the disease’s pathology. Unlike treatments that target amyloid plaques, PMN310 focuses on amyloid-beta oligomers, which could offer a unique and effective approach for AD patients.

Larry Altstiel, Chief Medical Officer of ProMIS Neurosciences, underscored the importance of these results for the upcoming Phase 1b clinical trial in Alzheimer’s patients. He expressed optimism that the Phase 1b trial, set to commence in the latter half of 2024, will provide further insight into the drug’s efficacy and optimal dosing.

The Phase 1a trial was a randomized, double-blind, placebo-controlled study conducted across two active sites in the United States. It enrolled 40 healthy volunteers to evaluate the safety, tolerability, and pharmacokinetics of intravenous doses of PMN310. The analysis of the first four cohorts has been completed, and the fifth cohort is undergoing final analysis. Expectations are that the fifth cohort will yield similar positive results.

ProMIS Neurosciences utilizes a proprietary target discovery engine that employs a thermodynamic and computational approach to predict novel targets on the molecular surface of misfolded proteins. This unique platform has enabled the development of PMN310, a humanized monoclonal antibody specifically designed to target soluble amyloid-beta oligomers, which are considered the most toxic form of amyloid-beta.

PMN310 aims to address the neurodegenerative process directly by inhibiting the binding of soluble amyloid-beta oligomers to neurons, thereby preserving synaptic function and preventing neurodegeneration. The positive data from the Phase 1a trial supports the potential of PMN310 as a novel therapeutic for Alzheimer’s disease, and the company is preparing to present the full dataset at an upcoming medical meeting in the second half of 2024.

ProMIS Neurosciences remains committed to advancing its pipeline of antibody therapeutics targeting misfolded proteins in neurodegenerative diseases. The company’s innovative approach and promising early clinical data position it as a noteworthy player in the quest for effective treatments for Alzheimer’s and other neurodegenerative disorders.