Cognito Therapeutics raises $100M for FDA-bound light-and-sound Alzheimer's device

Summary

Cognito Therapeutics, an MIT spinout, has closed a $100M+ oversubscribed round to fund the final stretch of its FDA push for a noninvasive Alzheimer's device that uses light and sound at 40Hz to stimulate brain activity.

Cognito CEO Christian Howell says the approach was widely dismissed as too simple to be plausible, which ultimately forced more than $1 billion in combined investment from MIT and Harvard to clinically validate it. Neurons firing above 40Hz drive biology that preserves synapses and myelin. Stimulating the optic nerve through flickering light and the cochlear nerve through sound at that frequency pushes the brain into what researchers call the gamma band, where that protective biology is active. The device is worn one hour a day at home.

The trial

Cognito is running the largest nondrug randomized clinical trial ever conducted, with 673 patients across 70 US sites over 12 months. The trial is fully enrolled and near completion. A feasibility study conducted before this trial showed 77% preservation of function and 76% preservation of cognition. Howell describes those results as best-in-class by a wide margin. No adverse events have been recorded.

Timeline

Cognito expects to read out Phase 3 results in August 2026, file with the FDA in November 2026, and target approval by mid-2027. The commercial path runs through CMS reimbursement, with patients receiving a personalized device for home use without clinic visits.

Market

About 6 million Americans are living with Alzheimer's. Another 15 million have mild cognitive impairment, the early stage of decline, with roughly 12 million of those undiagnosed. Howell puts the global affected population at nearly 50 million. Existing drug options such as the monoclonal antibody lecanemab are not indicated for advanced disease and carry meaningful side-effect risks.

Fundraise

The round was difficult to close. Cognito does not fit neatly into biotech or med tech categories, which pushed many conservative investors away. The oversubscription reflects confidence built around Phase 3 proximity and adherence data showing that 85 to 86% of trial patients wore the device at least 50 minutes a day six days a week, with nearly 90% wanting to continue after the study ended.

If the Phase 3 numbers hold near the feasibility results, Cognito will enter the FDA process with a strong efficacy profile, zero adverse events, and a home-use form factor that existing drug therapies cannot match.