Ensuring Success in Early Phase Oncology Clinical Trials The numbers of oncology drugs in clinical development is more than twice the number in any other therapeutic area (PharmaLive.com). Yet despite being the most commonly tested therapies, oncology drugs have the worst approval rates. Only 5% of agents with anticancer activity in preclinical development are licensed (Hutchison and Kirk, 2011). The main reason for failure is that preclinical strategies to evaluate novel oncology agents are suboptimal. In addition, conducting clinical trials in cancer patients is challenging because of the number and type of prior treatments patients have undergone and because novel agents are tested in patients with late-stage malignancies, which are inherently more difficult to treat than earlier malignancies. The current landscape of cancer therapeutics is evolving as the genetic and molecular mechanisms involved in cancer are increasingly understood. More targeted and individualized therapy has presented exciting possibilities to combat disease, but the new approaches have also added complexity to clinical development. In any disease state, conducting successful Phase 1 trials is a key component of ushering a novel therapy through clinical development. Although Phase 1 studies in most therapeutic areas consist of healthy patients, Phase 1 studies in oncology consist of patients with active disease. This creates unique challenges and potential opportunities. Understanding these challenges and opportunities is paramount for designing Phase 1 oncology studies and keeping them on track. Unique Aspects of Phase 1 Oncology Studies Oncology trials are bound to enrolling patients with later-stage disease who have already been treated with standard of care. The reason for this distinctiveness is an ethical one; any new investigational agent bears the potential of failure or suboptimal therapeutic efficacy, and the inclusion of early stage patients who do have proven treatments would be regarded as unethical unless the new agent has shown activity.