Implementing Project Optimus in Oncology Dosage Optimization: Where are We Now?

Determining the optimal dosage of oncology drugs is a critical component of drug development, as many anticancer agents are associated with high toxicity. With the emergence of targeted therapies and immunotherapies, the conventional concept that "more is better" may not apply, as higher doses do not necessarily yield greater efficacy and may compromise tolerability. In response to repeated post-approval dosage modifications, the U.S. Food and Drug Administration (FDA) launched Project Optimus in 2021 to promote data-driven, patient-centered dosage optimization. Despite the release of the finalized FDA Guidance for Industry on Oncology Dosage Optimization in 2024, sponsors continue to face challenges in translating these recommendations into practice, due to the complexity in the development process of oncology drugs and the limitations of early-phase trials. To gain insight into current practices and challenges, the DahShu Innovative Designs Scientific Working Group (IDSWG) conducted an industry-wide survey among oncology statisticians in biopharmaceutical companies. The survey revealed a shift away from reliance on the maximum tolerated dose toward integrated strategies balancing efficacy, safety, pharmacokinetics, and patient experience. This paper summarizes the findings from that survey and offers practical recommendations emphasizing cross-functional collaboration between statisticians and other functional members in early phase trials, adoption of innovative trial designs, and proactive regulatory engagement regarding dosage optimization strategies in clinical development.