OBJECTIVES: The emergence of gene therapy medicinal products (GTMP) has provided novel treatment options for rare diseases. Health technology assessment (HTA) agencies evaluate GTMPs but their reimbursement recommendations can differ, particularly the additional restrictions and real-world evidence (RWE) requirements. Our objective was to review the restrictions and RWE requirements included in HTAs of GTMPs.

METHODS: HTA reports describing reimbursement decisions, restrictions, and RWE requirements for 5 GTMPs (atidarsagene autotemcel (AA), onasemnogene abeparvovec [OA], voretigene neparvovec [VN], Strimvelis, and talimogene laherparepvec [TL]) across 7 HTA agencies (NICE [UK], G-BA [Germany], HAS [France], SMC [Scotland], PBAC/MSAC [Australia], CADTH [Canada], and ICER [US]) were assessed.

RESULTS: Overall, 20 HTA reports published between 2016 to 2022 were reviewed. All contained positive reimbursement outcomes except for 1 (G-BA's evaluation of OA). NICE evaluated and recommended all 5 GTMPs. A total of 67 restrictions were placed on reimbursement decisions across 5 categories: clinical (specialist prescribing/administration conditions) (38), price reduction (10), RWE generation (8), time limit for reevaluation (8), and risk sharing agreements (3). The number of restrictions per GTMP ranged from 0 to 8. OA and VN were both evaluated by all 7 HTA agencies, RWE generation was required from 5 for OA (NICE, G-BA, HAS, PBAC, and ICER) and from 4 for VN (G-BA, HAS, MSAC, SMC). All HTA agencies required RWE generation for at least 1 GTMP except for CADTH.

CONCLUSIONS: For indications that lacked effective disease modifying treatment options, GTMPs were recommended for restricted reimbursement in almost all cases. Requirements for price reductions and future reassessment after RWE collection were common, although not requested by all HTA agencies. This is likely due to the differing aims and methodologies of HTA bodies. As more GTMPs enter the market, HTA bodies may maintain disparate evaluation strategies, resulting in a heterogeneous treatment access landscape.