Predictability of OS with Subsequent Therapies or Treat Crossover in Oncology Clincal Trials

• Activity Number: 172
• Type: Contributed
• Date/Time: Monday, August 4, 2014 : 10:30 AM to 12:20 PM
• Sponsor: Biopharmaceutical Section
• Author(s): Jianchang Lin*+ and Guohui Liu
• Companies: Takeda and Takeda
• Keywords: Oncology ; PFS ; OS ; Cross Over ; Subsequent Therapies

Abstract

In oncology clinical trials, overall survival (OS) is the "gold standard" endpoint for the regulatory approval. However, it usually involves larger studies, and could be affected by the treatment cross over or other subsequent therapies. On the other hand, progression free survival (PFS) have gain more and more recognition and is considered as valid endpoint in most cancer clinical trials, which could result in smaller trial size and shorter follow-up. A typical oncology trial design are powered on both PFS and OS, with an interim OS analysis at the time of PFS analysis. Usually, OS is considered either as a co-primary endpoint or as a key secondary endpoint. Efficacy claim is often based on PFS benefit and interim OS results. In this work, we will conduct extensive simulation to evaluate the impact of OS with treatment cross over and subsequent therapies. The goal of the research is to provide quantitative tool to measure how interim PFS benefit could be translate in to OS benefit, which could be applied to trial planning and monitoring stage and facilitate the design decision making process.