We recently shared the results of a phase 2 study that evaluated the drug eribulin in two vascular sarcomas, angiosarcoma and EHE. To accompany this work, Dr. Tom Chen of National Taiwan University College of Medicine has shared important commentary in Clinical Cancer Research, highlighting the importance of interpreting data in a disease-specific manner and defining innovative endpoints for trials like this. Dr. Chen proposes a three-pronged approach to developing endpoints for ultra-rare sarcomas such as EHE. 

First, interpretation of results from clinical trials such as the eribulin study, which include patients with multiple types of sarcoma, must be done in a “histology-specific” manner. This means that conclusions about EHE in this case may not necessarily be applied to other sarcomas, and vice versa. 

Second, Dr. Chen argues that assessment methods, the tools that researchers and doctors use to determine if the cancer has responded to the treatment, must also be tailored to the unique features of the cancer being studied. This means that the ways researchers and scientists measure success for a patient with EHE might be different than the ways they measure success for a patient with another sarcoma. 

Finally, Dr. Chen emphasizes that clinicians and scientists, patient advocates, and regulatory agencies (such as the FDA in the United States and the EMA in Europe) must all be part of the conversation when designing and conducting trials like this. This collaboration will help ensure that results are not only interpretable but also usable in the effort to develop new therapies for patients around the world.

Why this matters:
This commentary highlights how clinical trials in ultra-rare cancers like EHE cannot be designed, conducted, or interpreted the same way as those for more common diseases. Trials must be tailored to the unique characteristics of the disease and carefully planned to enable international collaboration and interpretation of results. This work helps to contextualize the results of the phase 2 eribulin study and informs the planning of future trials.