Presentation (CTI)

OBJECTIVES: Spinal muscular atrophy (SMA) is a rare, inherited disorder characterised by progressive musculoskeletal, respiratory, and bulbar dysfunction, leading to early mortality. Disease-modifying therapies (DMTs), including risdiplam, are available in England under Managed Access Agreements (MAAs). Due to limited clinical and cost-effectiveness data, patients with SMA requiring permanent ventilation (SMA-PV) are excluded from DMT under the MAA criteria. Additionally, the MAA monitoring assessments and stopping rules are unsuitable for SMA-PV. Collecting evidence to support reimbursement in rare disease populations presents significant challenges, especially due to the lack of validated criteria for clinical benefit in unique subgroups like SMA-PV. To address these gaps, a Delphi consensus process was conducted.
METHODS: Nineteen UK clinical experts with experience managing patients with SMA or SMA-PV were recruited. Draft statements, informed by published evidence, expert experience, and patient insights, were anonymously voted on across up to three rounds. Experts indicated their level of agreement for each statement in each round and provided feedback for any disagreement. Statements with less than 75% agreement were revised for subsequent rounds based on received feedback.
RESULTS: All 22 draft statements achieved consensus (range: 88.9-100%) after two voting rounds, with a 100% participation rate. Statements covered seven thematic areas, offering practical recommendations for managing patients with SMA-PV with DMTs, defining clinical benefit, and considerations for future research. Statements regarding equitable access achieved over 94% agreement and statements relating to the monitoring of health-related quality-of-life reached 100% agreement.
CONCLUSIONS: For rare disease populations, such as SMA-PV, Delphi consensus processes can provide alternative methodologies for generating guidance where robust clinical evidence generation is challenging. It is hoped these insights could support payer decision-making, enhance access to DMTs, guide clinical practice concerning DMT use and improve outcomes for this underrepresented group. While only UK experts were consulted, it is hoped these outcomes can guide global clinical practice.