Lugano, Switzerland, 23 May 2025 – The European Society for Medical Oncology (ESMO) is pleased to announce the publication of the latest version of the scale that measures the clinical benefit of cancer treatments, the ESMO-MCBS (ESMO-Magnitude of Clinical Benefit Scale).
"ESMO-MCBS v2.0 is more than just a technical revision of the scale," says Sjoukje Oosting, Chair of the ESMO-MCBS Working Group. "ESMO-MCBS v2.0 brings significant enhancements in the evaluation of cancer therapies, because it is more robust, it is aligned with the changing treatment landscape, and adds to the accuracy, fairness, and utility of treatment assessments."
ESMO-MCBS v2.0 is the outcome of a comprehensive revision process consolidating numerous feedback from different stakeholders, including patients. This version incorporates 13 critical amendments, including a new evaluation form for single-arm de-escalation studies in the adjuvant setting. Overall, the changes impact the scores of 13.6% of evaluated studies and add toxicity annotations to 45.5% of the studies in the curative setting.
Toxicity annotations have been added for curative treatments after consultation with patient representatives. "When cure is a possibility, thresholds for toxicity trade-off acceptance can vary between patients," observes Oosting. By adding a toxicity annotation, clearly signposted for the end-user, the scale provides adequate forewarning of the likelihood of severe toxicities without penalising the grading of the medicine. "This refinement ensures that the scale is mindful of patient preferences, ensuring a balanced understanding of treatment benefits and risks," Oosting notes.
Reflecting the overall aim for increased rigour, the ESMO-MCBS v2.0 version continues to clearly indicate cases where the underlying data—such as progression-free survival and overall survival results – are still immature or pending, offering clarity and transparency in the interpretation of data at a time when fast approval of drugs requires the scoring to happen as quickly as possible, yet with data that is non final.
ESMO-MCBS v2.0 scoring criteria are generally more stringent and methodologically refined, particularly in the curative setting, enhancing the tool's robustness and reliability (1).
This version ensures that the scale is aligned with current clinical practice, offers a more solid and transparent framework to evaluate the magnitude of clinical benefit, and sets the stage for further ongoing improvements (2).
"The release of ESMO-MCBS v2.0 marks a major step forward in ESMO's mission to promote value-based cancer care, and clearly reflects ESMO's ongoing commitment to ensuring that the scale remains a robust, transparent, and clinically meaningful tool for evaluating the magnitude of benefit from new cancer therapies against a backdrop of a rapidly evolving clinical trial landscape," says ESMO President Fabrice André. "As a trusted guide for treatment decision-making, ESMO-MCBS ensures that the benefits and toxicities of treatments are thoroughly assessed, which leads to better-informed clinical decisions and ultimately better care for patients," he says.
The development of ESMO-MCBS v2.0 involved a transparent process with extensive peer review, appeal, and revision opportunities. This ensures the accountability for reasonableness of the scores, making the scale a trusted decision-support tool. The amendments incorporated into ESMO-MCBS v2.0 will be applied to the ESMO-MCBS Scorecards ensuring all current and future evaluations reflect the updated scoring methodology.
