Cortexyme Announces Phase 2/3 Clinical Trial Based on Transformational Understanding of Alzheimer’s Disease Now Open for Enrollment

Cortexyme, Inc. today announced the launch of the GAIN Trial, an international Phase 2/3 clinical study of the companys lead investigational medicine, COR388, in subjects with mild to moderate Alzheimers disease (AD). A first wave of U.S. trial sites are now screening patients for participation, and additional trial centers in the United States and Europe are expected to be open for enrollment in the coming months. Potential participants and caregivers can learn more about the study by visiting the trial website at

The GAIN (GingipAIN Inhibitor for Treatment of Alzheimers Disease) Trial is based on a growing body of scientific evidence that the pathogenic bacterium Porphyromonas gingivalis, or P. gingivalis, most commonly associated with chronic periodontal disease, can infect the brain and cause AD. The trial is evaluating whether COR388, an oral investigational medicine, can slow or halt the progression of AD by inactivating the toxic proteins, or gingipains, released by P. gingivalis that have been shown in animal models to damage and destroy brain cells.

The GAIN Trial is the first large, international clinical trial to test a dramatically new way of understanding and treating Alzheimers disease, said Marwan Sabbagh, M.D., the director of the Cleveland Clinic Lou Ruvo Center for Brain Health, one of the clinical research centers for the study. For decades, a significant portion of the Alzheimers research community has focused on approaches related to amyloid plaques found in the brains of patients with the disease. In the GAIN Trial, we are evaluating a new and different mechanism of action against Alzheimers. We hope to confirm the hypothesis that bacteria are an ˜upstream trigger for Alzheimers, and that inactivating the toxic proteins released by the bacteria can have a positive impact on stopping or slowing the progression of this devastating disease.

COR388 is a first-in-class, orally administered virulence factor inhibitor that targets P. gingivalis gingipains. In a paper published in Science Advances earlier this year, a team of researchers, including Cortexymes chief scientific officer, Dr. Stephen Dominy, M.D., detailed preclinical data on COR388s ability to reduce the bacterial load of a P. gingivalis infection, block production of amyloid beta, reduce neuroinflammation, and protect neurons in the hippocampus, a part of the brain that mediates memory. In late 2018, Cortexyme presented encouraging results from a Phase 1b clinical trial showing COR388 was well-tolerated, and identifying positive trends across several biomarkers and cognitive tests in patients with AD.

The GAIN Trial is a randomized, double-blind, placebo-controlled Phase 2/3 trial that aims to recruit more than 570 participants at more than 90 sites in the United States and Europe. To participate in the study, subjects must be 55-80 years of age with a documented diagnosis of mild to moderate AD, among other criteria. Subjects will be randomized to one of two doses of COR388 (twice daily 40mg or 80mg), or placebo. The primary endpoint for the study is mean change in the Alzheimers Disease Assessment Scale-Cognitive Subscale 11 (ADAS-Cog 11) from baseline to 48 weeks. Secondary and exploratory endpoints include change in Alzheimers Disease Cooperative Study Group-Activities of Daily Living (ADCS-ADL), change in Clinical Dementia Rating-Sum of Boxes (CDR-SB), Winterlight Speech Assessment, cerebral spinal fluid biomarkers of infection, and other measures.

The start of the GAIN Trial is an important milestone as we work to bring new hope and options to patients with Alzheimers, said Michael Detke, M.D., Ph.D., Cortexymes chief medical officer. The clinical rationale for the study, and the data that support a bacterial driver of Alzheimers disease, are compelling. We look forward to enrolling subjects and learning more about the potential for COR388 to benefit the Alzheimers patient community, which now numbers more than 5.7 million people in the United States and 30 million individuals worldwide.

About Cortexyme, Inc.

Cortexyme is a clinical-stage pharmaceutical company pioneering a novel disease-modifying therapeutic approach to treat a key underlying cause of Alzheimer’s disease and other degenerative diseases. Cortexyme is targeting a specific, infectious pathogen found in the brain of Alzheimers patients and tied to neurodegeneration and neuroinflammation in animal models. The company’s lead investigational medicine, COR388, is the subject of the GAIN Trial, an ongoing Phase 2/3 clinical study in patients with mild to moderate Alzheimers. More information about the trial can be found at To learn more about Cortexyme, visit

Hal Mackins
For Cortexyme, Inc.
[email protected]