The costs of developing treatments for Alzheimer's disease: A retrospective exploration

INTRODUCTION: With the exception of the recent accelerated approval of aducanumab, in over 26 years of research and development (R&D) investment in Alzheimer's disease (AD), only five novel drugs—all for symptomatic treatment only—have reached FDA approval. Here, we estimate the costs of AD drug development during this period in the private sector. METHODS: To estimate private R&D funding, we collected information on AD clinical trials (n = 1099; phases 1–4) conducted between January 1, 1995 and June 21, 2021 from various databases. Costs were derived using previously published methodologies and adjusted for inflation. RESULTS: Since 1995, cumulative private expenditures on clinical stage AD R&D were estimated at $42.5 billion, with the greatest costs (57%; $24,065 million) incurred during phase 3; approximately 184,000 participants were registered or are currently enrolled in clinical trials. DISCUSSION: Measures to reduce expenditures while moving toward disease‐modifying therapies that alleviate the rising burden of AD require continued investment from industry, government, and academia.