Challenges in biomarker-based clinical trials for patients with gastrointestinal malignancies

ABSTRACT Introduction The goal of precision oncology is to match each patient with the most appropriate therapeutic agent based on patient- and tumor-specific characteristics. Many therapeutics in development target tumors with specific biomarkers, in addition to considering tumor histologic classification and clinical presentation. Areas Covered Appropriate patient selection for research studies is critical to elucidate the potential effectiveness of therapies in development, as well as to spare the toxicities from ineffective therapies in patients who are unlikely to benefit. Biomarker-based clinical studies provide a platform to bring forward the expanse of therapeutics beyond the use of chemotherapy, including novel immunotherapeutic and targeted strategies. There are a number of issues to be considered when developing these types of studies. They range from biomarker validity to patient enrollment and trial availability. In this review, we discuss challenges that are frequently confronted in the design, enrollment, and analysis of biomarker-based clinical trials for patients with gastrointestinal (GI) cancers. Expert opinion The challenges encountered in biomarker-based trials for patients with GI cancers must be considered and addressed early during drug development to ensure proper therapy and patient selection in a timeframe acceptable for both patient diseases and rapidly changing oncology standards.