FDA releases draft of accelerated approval guidance for oncology therapeutics
pharmafile | March 27, 2023 | News story | Medical Communications |
The FDA has released a draft of new guidance for accelerated approval for oncology therapeutics, highlighting the need for stricter clinical trial design.
Clinical Trial Considerations to Support Accelerated Approval of Oncology Therapeutics is a non-binding draft focusing on how clinical trial design can be optimised to secure the best possible results while being flexible enough to adapt to the unique needs of every trial. Oncology drugs commonly use the accelerated approval pathway due to the serious and life-threatening nature of cancer, which allows companies to pursue approval based on surrogate or intermediate clinical endpoints.
Traditionally, single-arm trial designs and response endpoints have been used in accelerated approval trials as malignant tumours typically do not regress on their own, meaning any response is clinically significant, and this endpoint can be seen in single-arm trials for monotherapy oncology drug regimens.
However, the FDA’s draft is now recommending randomised controlled trials to combat some of the limitations of single-arm trials. Limitations include ‘safety databases [which are] typically small and may not allow for the identification of rare…adverse effects…Attribution of adverse events to the drug under study can be limited in the absence of a comparator arm.’ and ‘common time-to-event efficacy endpoints in oncology… [which are] are generally uninterpretable due to failure to account for known and unknown confounding factors when comparing results to an external control.’
To combat the lack of long-term data resulting from single-arm trials, the FDA outlines how separate randomised controlled trials can be conducted which allow for a shorter-term efficacy endpoint to be achieved (response rate), as well as a longer-term clinical endpoint such as progression-free survival (PFS) or overall survival (OS). It also notes, however, that single-arm trials will still be considered if randomised controlled trials are inappropriate for the particular drug being tested.
James Spargo
