Evaluating Magnitude of Clinical Benefit in the GIST, STS Treatment Landscape
A retrospective analysis of clinical trials associated with The European Society for Medical Oncology-Mangnitude of Clinical Benefit Scale version 1.1 (ESMO-MCBS) were presented at the virtual 2021 ESMO Congress.
The ESMO-MCBS, a reproducible and validated medical device, is used to assess the magnitude of clinical benefit from drugs for solid tumors and outcomes supporting drugs used in advanced Soft Tissue Sarcomas (STS) and gastrointestinal stromal tumors (GIST).
“We reviewed publications between January 1990 and December 2020 that support the recommendations of NCCN (National Comprehensive Cancer Network) guidelines version 1.2021 for treatment of advanced STS and GIST,” explained Raul Lleida, MD, Department of Medical Oncology, Hospital de la Santa Creu i Sant Pau, Spain, and co-investigators.
Primary data was collected from trial characteristics, efficacy, toxicity, and quality of life (QoL). ESMO-MCBS grades were applied to each trial. Substantial clinical benefit was assigned as a grade 4 or 5 on a scale of 1 to 5.
Out of 23 trials associated to the use of ESMO-MCBS (40.4%), 13 (56.5%) were randomized controlled trials (RCT; eight phase 3 and five phase 2) and 10 (43.5%) were single arm trials. Eighteen (78.2%) involved STS and 5 (21.8%) GIST. Six trials (26.1% of all trials and 46.1% of RCT) showed improvement in overall survival (OS).
QoL was reported in 7 (30.4%) trials and only 3 (42.9%) showed improvement in QoL.
Only 9 (39.1%) trials met the ESMO-MCBS substantial benefit threshold with four phase 3 and four phase 2 trials (27% involving STS and 80% involving GIST). All 3 trials that reported QoL improvement met the threshold of providing substantial benefit according to the scale.
“These results suggest that randomized trials with QoL assessment are more likely to achieve the ESMO-MCBS substantial benefit threshold. Only a quarter of the trials showed improvement in OS,” concluded Dr Lledia, et al. – Alexa Stoia
