Update on Investigational Drugs for Alzheimer’s Disease

We heard much about drugs in development to treat or delay the onset of Alzheimer’s disease during 2018. There are twenty-five investigational drugs targeting Alzheimer's disease currently in the Pharmaceutical Pipeline Tracker. None of the drugs have PDUFA dates at this time although there are five drugs with FDA Priority Designations.

Progress was anticipated in the treatment of the disease this year. But the newswires have become largely radio silent. Following is an example of what we did hear.

In March Biogen announced that an interim analysis by an independent committee of two Phase III trials involving patients with mild cognitive impairment due to Alzheimer's disease and mild Alzheimer's disease dementia. The interim futility analysis was based on data from 1,748 patients and found a low likelihood that aducanumab would improve or slow cognition in Alzheimer’s patients, so Biogen discontinued both trials in March 2019. 

In the meantime, Biogen analyzed addition data from 3,285 patients, of which 2,066 had completed the full 18 months of treatment and found a reduction in cognition reduction compared to placebo in the one of the trials’ data. The benefit was primarily from an analysis of an expanded cohort of patients which found a reduction in the decline in cognition with the higher dose of aducanumab as demonstrated by improvements over 78 weeks in 547 patients compared to placebo in CDR-SB (23%), MMSE (15%), ADAS-Cog 13 (27%) and ADCS-ADL-MCI (40%). The expanded cohort of high dose patients did not demonstrate an improvement compared to placebo. Biogen will offer patients enrolled in the two trials continued access to aducanumab, along with the long-term extension study for a Phase 1b study, and safety study of the data from one of the previous Trials. Biogen plans to file a BLA for aducanumab in early 2020.

Ten trials of investigational drugs targeting Alzheimer’s have been discontinued. Of those attempts still in progress a number of pathways are under investigation. For example: monoclonal antibodies, BACE Inhibitors, amyloid beta protein inhibitors, caprilic triglycerides, and beta ameloid reduction. One of the companies involved in the research has gone out of business. Another has no ongoing US trials.

Most of the ongoing Phase III trials are slated to deliver results no earlier than late 2020.