By: Richard Pazdur, M.D.
Over the past decade, advances in understanding of cancer biology have led to the development of targeted treatments that are more effective than the chemotherapies of the past century. These therapies are demonstrating response rates large in magnitude or response durations prolonged in early trials, or both. Patient demand to enter these trials has increased, and so have calls to expedite the drug development and approval processes, all while maintaining high standards for safety and efficacy. We never lose sight of our dedication to patients faced with a life-threatening disease and to making progress in the fight against cancer.
The FDA works with industry, researchers, and other stakeholders developing innovative cancer therapies. We must ensure clear understanding of our latest thinking on how clinical trials can be efficiently and effectively designed to demonstrate a cancer therapy’s safety and efficacy.
Last week, the FDA published a draft guidance to help advance effective and innovative clinical trial designs early in drug development to help bring new cancer therapies to patients as quickly as possible. Below is a quick summary of this guidance:
Traditionally, clinical trials have been conducted in phases with one or two main objectives per study. For example, phase 1 studies help determine safety and the dose range for exploration in future trials, while phase 2 studies provide preliminary evidence of safety and activity in a single setting. This latest guidance, Use of Expansion Cohorts in First-In-Human Clinical Trials to Expedite Development of Cancer Drugs and Biologics, provides advice on designing and conducting adaptive trial designs in which pharmaceutical companies and researchers can assess many different aspects of a drug in development in a single clinical trial while enrolling the minimum number of study participants necessary to obtain this information. Trials with multiple expansion cohorts can be inherently more efficient and expedite early drug development. They can allow for addressing multiple questions in a single trial that is amended as new objectives are identified, avoiding the time lag and additional resources experienced with the opening of new clinical trials.
The principal advantage of expansion cohort trials is efficiency in drug development, with the goal of making highly effective drugs widely available to the public as quickly as possible. Well-designed and well-conducted clinical trials help ensure patient safety while also obtaining quality data that may support drug approval. This new draft guidance describes our proactive steps to help industry design clinical trials for today’s highly complex cancer therapies—and to conduct these trials in cost-effective and timely ways.
From 1990 through 2014, the overall cancer death rate in the United States fell by 25 percent. In 2014, the number of people living beyond a cancer diagnosis reached 14.5 million, and by 2024, is expected to climb to approximately 19 million. In 2017, the FDA approved 16 new cancer drugs and biologics, including the first two in an exciting new category called CAR-T cell therapy. We also approved 30 new indications (uses) for existing cancer drugs and biologics, and the first two biosimilars indicated to treat cancers. Additionally, we recently approved the first cancer treatment based on a genetic feature of a cancer rather than the location of the body where the tumor originated.
The new draft guidance is intended to help the drug development community continue this progress against cancer. We want your input to make sure that the final guidance is comprehensive and forward looking and adapts to rapidly changing research developments and technologies. Our regulatory work needs to remain as advanced as the many new cancer therapies currently working their way through development. We encourage stakeholders to comment and look forward to your valuable feedback.
Richard Pazdur, M.D., is Director, FDA Oncology Center of Excellence