Alector (ALEC) TD Cowen 46th Annual Health Care Conference summary

Platform and technology overview

• Focus on the ABC platform, enabling delivery of antibodies, enzymes, and siRNAs across the blood-brain barrier using transferrin receptor (TFR) targeting.

• Developed a proprietary ABC epitope on TFR to maximize brain uptake and minimize safety liabilities like anemia.

• Demonstrated significant improvements in brain uptake and safety profile in both murine and non-human primate (NHP) models.

• ABC platform supports subcutaneous administration for all modalities, aiming for patient-friendly dosing.

Lead programs and preclinical data

• Lead anti-amyloid beta (Aβ) antibody (AL137) shows >30-fold brain uptake increase and strong phagocytosis without added safety risks.

• AL137 outperforms competitors in brain uptake at lower doses and is well-tolerated at both therapeutic and high doses in NHPs.

• ABC-enabled GCase enzyme (AL050) for Parkinson’s and Lewy body dementia demonstrates 50x activity over wild-type, with sustained substrate reduction and no adverse events.

• siRNA platform, in partnership with Axolabs, achieves potent, widespread brain knockdown via IV or subcutaneous dosing, outperforming intrathecal delivery.

Clinical development plans

• IND submission for AL137 targeted for Q4 this year or Q1 2027, with first-in-human dosing soon after.

• Phase 1 to start with single ascending dose in healthy volunteers, including subcutaneous arm, then move to multiple ascending dose in early Alzheimer’s patients.

• Key readout will be amyloid clearance via PET imaging, aiming for rapid demonstration of efficacy in 10–15 patients.

• Phase 1 will focus on showing amyloid reduction without significant ARIA or anemia, leveraging established clinical sites.

• Follow-up duration designed to capture maximal amyloid clearance, with extension for ongoing biomarker collection.