Using proprietary assays, Cognition Therapeutics Inc. has discovered small-molecule, highly brain-penetrable drugs that block soluble toxic amyloid beta oligomers in their reactive form, rather than target amyloid beta plaque or expression of the monomer building blocks.

AlzProtect SAS believes that Alzheimer's disease is caused by the loss of neuroprotective factors including APP intracellular domain and sAPP alpha, both of which are produced during the metabolism of amyloid precursor protein. The start-up is developing compounds that can stimulate the APP, increasing the production of neuroprotective compounds.

With big Phase III failures heating debate about the amyloid hypothesis, small biotechs must convince investors that their early research is pointed in the right direction, and larger ones must design clinical trials with care. We profile four Alzheimer's-focused start-ups in this issue: AlzProtect, Axerion Therapeutics, Cognition Therapuetics and Galantos Pharma.