The Feasibility of Personalized Endpoints in Assessing Treatment Outcomes for Rare Diseases: A Pilot Study of Goal Attainment Scaling in SCN2A-Associated Developmental Epileptic Encephalopathy

Objectives For individuals living with rare neurodevelopmental disorders, particularly those who are at the most severe end of the spectrum, standardized outcome measures may lack the sensitivity to capture small but meaningful changes. Personalized endpoints such as goal attainment scaling (GAS) allow the assessment of treatment response across variable baseline states and disease manifestations and, thus, provide a highly sensitive measure of efficacy. The current study tested the feasibility of using GAS in rare SCN2A-associated developmental and epileptic encephalopathy (SCN2A-DEE). Methods The caregivers of 10 individuals with SCN2A-DEE (Mage = 8.2 years, SD = 5.62, range 3.4-20.4; Nmale = 8) took part in in-person goal setting and remote follow-up interviews facilitated by 4 clinical researchers. Implementation was standardized using clinician training, patient orientation, and an electronic data capture platform, GoalNav®; surveys were used to evaluate implementation. Results All 10 caregivers completed the goal-setting interviews and were able to set scale 3 goals, and assess attainment levels at follow-up interviews. The mean (SD) times to conduct the goal setting and follow-up interviews were 59.4 (14.5) and 18.4 (10.5) minutes, respectively. Participants set a variety of goals relating to communication (n = 10), feeding (n = 4), gross and fine motor abilities (n = 6), behavior (n = 5), gastrointestinal function (n = 3), sleep (n = 1), and seizures (n = 1). Data completeness, interview time, and the presence of high-quality goals (29/30) indicated the feasibility of using GAS in this population, whereas survey responses indicated its acceptability. Conclusions This pilot project provided evidence supporting the feasibility of GAS as a method for assessing treatment outcomes for patients with rare neurodevelopmental disorders.