Researchers developed a pair of novel clinical outcome assessments in furtherance of improving the clinical evaluation of Duchenne muscular dystrophy (DMD) patients during clinical trials. “Currently no disease-specific global impression of change items exists which directly assess the symptoms and functional abilities important to individuals with Duchenne from a patient-centered perspective,” the study authors said.
Working together with DMD patients, caregivers, and clinicians, Staunton et al designed the Duchenne Clinical Global Impression of Change (CGI-C) and the Caregiver Global Impression of Change (CaGI-C) items, and implemented them in the phase 2/3 clinical trial (NCT03039686) of RG6206 (RO7239361).
To draft the 2 items, as well as the respective instructions, the researchers collected data from concept elicitation interviews (n=19). These interviews highlighted relevant symptoms and meaningful alterations in the functional abilities of DMD patients.
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Participants reported muscle weakness, fatigue, cardiac difficulties, and pain as frequent symptoms. Moreover, they affirmed that “small changes in functional ability were meaningful, particularly when independence was impacted.” Overall, they recommended the consideration of DMD patients’ speed, endurance, and quality of movement. Also, participants considered DMD patients’ ability to keep up with their peers and to complete daily tasks as useful indicators.
The study team discussed with clinicians and caregivers the relevance and understanding of the drafted content, during cognitive debriefing interviews. Participants described CGI-C and CaGI-C as relevant, appropriate, and clear documents.
RG6206 (RO7239361), formerly known as BMS-986089, is an anti-myostatin agent. The phase 2/3 clinical trial (NCT03039686), called SPITFIRE and sponsored by Roche, recruited 166 boys with DMD to assess the safety, efficacy, and tolerability of RG6026. Due to the lack of efficacy, the study was discontinued.
Staunton H, Trennery C, Arbuckle R, et al. Development of a Clinical Global Impression of Change (CGI-C) and a Caregiver Global Impression of Change (CaGI-C) measure for ambulant individuals with Duchenne muscular dystrophy. Health Qual Life Outcomes. 2021;19(1):184. doi:10.1186/s12955-021-01813-w
Clinical trial to evaluate the efficacy, safety, and tolerability of RO7239361 in ambulatory boys with Duchenne muscular dystrophy. ClinicalTrials.gov. February 1, 2017. Updated December 21, 2020. Accessed July 29, 2021.