Significance of emerging clinical oncology endpoints in support of overall survival

Despite a better understanding of the pathophysiology and development of newer therapeutic options, cancer remains an area with several unmet needs. Although overall survival (OS) remains a gold standard endpoint for all cancer therapies, it poses challenges such as the requirement of a long-term follow-up, a higher number of patients, and a higher financial burden. Therefore, surrogate endpoints such as progression-free survival, time to progression, duration of response, and objective response rate are being investigated and used in oncology studies. Patient-related outcomes that measure the patient's overall health, quality of life, and satisfaction in the long term are crucial surrogate endpoints considered for drug approval. Surrogate endpoints shorten oncology clinical studies and accelerate the evaluation and implementation of newer therapies. Emerging surrogate endpoints such as biomarkers, immune-related response criteria, minimal residual disease, and pathological complete response are increasingly being considered in oncology trials. Validation of surrogate endpoints enables their substitution for OS and gain market approval. The selection of surrogate endpoints for an oncology trial depends on cancer type and stage, the purpose of treatment, and expected duration of survival for the relevant disease. With the advent of individualized approach and complex study designs, the field of oncology is currently undergoing a paradigm shift. The use of newer surrogate endpoints will aid in accelerating the drug development process, making patient care for oncology more accessible.