Boston-based Acta Pharmaceuticals, Inc. announced on October 15, 2026 that it has secured US$24 million in Seed financing to advance a pipeline of therapies designed for early intervention in Alzheimer's disease. The company also disclosed that its lead candidate, GSM-779690T, has entered a Phase 1 clinical study. Acta was founded to translate more than four decades of scientific discoveries by neuroscientist Dr. Rudolph E. Tanzi into new Alzheimer's disease treatment and prevention options.
Seed Financing and Company Mission
The Seed round includes support from the Alzheimer's Disease Research Foundation, Dolby Family Ventures, Gamma Bio Investors, and several family offices and mission-driven investors. Acta will use the capital to advance GSM-779690T, expand its combination therapies pipeline, and support early clinical development. The company's work builds on Dr. Tanzi's co-discovery of the familial Alzheimer's disease genes APP, PSEN1, and PSEN2, which helped reshape scientific understanding of the disease.
Lead Candidate GSM-779690T
GSM-779690T is a next-generation gamma-secretase modulator being developed as a potential best-in-class oral therapy for Alzheimer's disease. It reduces levels of amyloid-beta 42, which drives senile plaque formation, while increasing protective amyloid-beta 37 and amyloid-beta 38, which interfere with plaque formation. Preclinical studies showed that the candidate preserved cleavage of the gamma-secretase substrate Notch at concentrations up to 20 micromolar.
This selective modulation differs from earlier gamma-secretase inhibitors, which broadly block the enzyme and can disrupt normal biological functions. It also contrasts with approved therapies that remove amyloid beta after it has accumulated in the brain as plaques. Acta is developing the molecule as a long-duration therapy for early intervention and eventual prevention, and Dr. Tanzi described the long-term vision as a once-daily oral therapy similar to a statin for the brain.
Phase 1 Study and Preclinical Data
The Phase 1 study appears under ClinicalTrials.gov ID NCT07690228 as a randomized, double-blind, placebo-controlled, single- and multiple-ascending-dose trial. It is designed to evaluate the safety, tolerability, and pharmacokinetics of GSM-779690T in healthy adult volunteers. Preclinical results highlighted single-digit nanomolar potency against amyloid-beta 42, a near 1:1 brain-to-plasma ratio in mice, and oral bioavailability across multiple species.
Combination Therapies and Drug Screening Platform
Acta's combination therapies program leverages Alzheimer's-in-a-Dish models, including mini-organoids and assembloids that recreate key features of Alzheimer's disease and the aging brain. The platform enables researchers to screen hundreds of FDA-approved drugs and natural products simultaneously in about six weeks. Using this approach, Dr. Tanzi and Massachusetts General Hospital colleagues have identified more than 30 validated combinations that curb Alzheimer's pathology, and Acta is now advancing select candidates toward clinical evaluation.
Leadership Commentary
Chief Executive Officer George Alex stated that GSM-779690T is the culmination of 25 years of research by Dr. Tanzi and the late Dr. Steven L. Wagner at Massachusetts General Hospital and the University of California, San Diego. He noted that the program was supported by approximately US$70 million in preclinical development funding. Chief Scientific Officer Kevin Rynearson added that hundreds of analogues were evaluated to optimize potency, brain penetration, and drug-like properties, yielding a structurally distinct development candidate.
Acta's Seed financing and Phase 1 initiation mark a meaningful step toward moving Alzheimer's care from late-stage plaque removal to early intervention and prevention. The company is targeting a public health crisis that currently affects more than seven million Americans. By pairing a potential best-in-class gamma-secretase modulator with a broader combination therapy pipeline, Acta aims to create multiple options for treating and preventing Alzheimer's disease.