Alector, Inc. announced that the first patient has been dosed in PROGRESS-AD, the global Phase 2 clinical trial of AL101/GSK4527226 in patients with early Alzheimer?s disease (AD), including mild cognitive impairment and mild dementia due to AD. AL101 is an investigational human monoclonal antibody designed to block and downregulate the sortilin receptor to elevate the level of progranulin in the brain in a manner similar to investigational latozinemab but with different pharmacokinetic (PK) and pharmacodynamic (PD) properties. Alector and GSK are co-developing and will be co-commercializing AL101 for the potential treatment of more prevalent neurodegenerative diseases, including AD and Parkinson?s disease.

PROGRESS-AD is a randomized, double-blind, placebo-controlled Phase 2 clinical trial of AL101 enrolling approximately 282 patients with early Alzheimer?s disease at multiple sites globally. The 76-week study is designed to assess the safety and efficacy of two dose levels of AL101 compared to placebo. Participants will be randomized to one of three treatment groups, receiving AL101 or placebo intravenously.

The primary endpoint of the study is disease progression as measured by the Clinical Dementia Rating Sum of Boxes (CDR®-SB). The CDR-SB is a validated instrument that tracks the progression of cognitive impairments in various categories. The trial also employs other clinical and functional outcome assessments.

The Phase 1 study of AL101 was a randomized, double-blind, placebo-controlled study in 88 healthy volunteers who received either single or multiple doses of AL101 administered intravenously (IV) or subcutaneously (SC). The study found that AL101 was generally well tolerated and increased progranulin (PGRN) levels in plasma and cerebrospinal fluid (CSF) in a dose-dependent manner. The study results demonstrated that the PK and PD profile supported the progression to Phase 2 clinical trials for more prevalent neurodegenerative conditions, such as AD and Parkinson?s disease.