Exhibit 99.1 Alector Reports First Quarter 2024 Financial Results and Provides Business Update Data from INVOKE-2, evaluating the most advanced TREM2 candidate in clinical development for early Alzheimer’s disease, on track for Q4 2024 Strengthened leadership team with key appointments: Neil Berkley, M.S., M.B.A., named Chief Business Officer; Errol De Souza, Ph.D., and Mark Altmeyer, M.B.A., join Board of Directors $562.1 million in cash, cash equivalents and investments provide runway through 2026 South S ...