SIO’s ACCLAIM Trial Completes Enrollment

August 5, 2025—The Society of Interventional Oncology (SIO) recently announced the completion of enrollment for its clinical trial, ACCLAIM—Ablation With Confirmation of Colorectal Liver Metastases. This milestone was achieved 8 months ahead of schedule, noted SIO.

According to the society, the ACCLAIM trial enrolled 240 patients (330 tumors) diagnosed with colorectal cancer liver metastases. The study was conducted in collaboration with nine leading cancer centers across the United States and Europe. In March 2023, SIO announced commencement of the trial.

SIO stated that in the trial, tumors were treated using FDA-cleared and/or CE Mark-approved microwave ablation systems and advanced margin confirmation software. The study’s primary endpoint is local disease progression at 2 years postablation, with the aim to determine whether complete margin coverage during ablation correlates with long-term tumor control.

The society-sponsored ACCLAIM trial is a global, prospective study that incorporates an objective and reproducible technical endpoint into its design that sets a new standard for clinical research in interventional oncology, advised SIO.

Further, the society noted that the study includes a collaboration across the medical device industry, with funding provided through grants from Boston Scientific Corporation, NeuWave Medical, Inc. (a subsidiary of Ethicon, Inc.), and Varian, a Siemens Healthineers company.

Additional information about ACCLAIM is available on SIO’s website at www.sio-central.org/ACCLAIM-Trial.

SIO President Alexis Kelekis, MD, and ACCLAIM Principal Investigator Constantinos T. Sofocleous, MD, commented on the enrollment achievement in the society’s press release.

“The early completion of patient enrollment in the ACCLAIM trial marks a pivotal moment in interventional oncology,” stated Dr. Sofocleous. “For the first time, we are prospectively validating a reproducible technical endpoint—ablation margin confirmation—in a multicenter trial, that not only redefines procedural success but more importantly, improves outcomes for patients with colorectal liver metastases.”

Dr. Kelekis added, “As the first society-sponsored study in the field, ACCLAIM sets a new precedent for clinical research. Its success reflects the power of collaboration between leading institutions and industry partners, and it paves the way for more precise, evidence-based approaches to cancer treatment.”