Tissue agnostic drug development represents a pivotal shift in oncology, moving away from the traditional classification of cancers based on their location in the body. Instead, it emphasizes a treatment approach centered on genetic markers that identify biologically rational subsets of cancer. This methodology is particularly beneficial for rare and pediatric cancer populations, where conducting dedicated clinical trials is often challenging due to limited patient enrollment. By focusing on genetic aberrations common across various cancers, tissue agnostic therapies provide a more inclusive framework for research and treatment, enhancing the potential for effective therapies in these underrepresented groups.

The U.S. Food and Drug Administration (FDA) has been instrumental in the advancement of tissue agnostic drug development, emphasizing treatment based on genetic markers rather than cancer's location. Notably, pembrolizumab (Keytruda) and larotrectinib (Vitrakvi) were the first two drugs to receive FDA approval under this new paradigm. Keytruda, a biologic, and Vitrakvi, a small molecule drug, exemplify the FDA's commitment to fostering personalized medicine.

Bringing tissue agnostic drugs to market requires the concurrent development of a companion diagnostic test, used to detect the biomarker indicating the drug's efficacy. This dual development process, involving both the drug and its diagnostic test, poses a significant challenge for biotech and pharma companies. Post-FDA approval, the focus shifts to educating healthcare providers and patients about the integrated use of these products. Additionally, limited reimbursement for the companion diagnostic by insurance and government programs like Medicare and Medicaid often hinders patient access to these potentially beneficial drugs.