Methods and criteria for the assessment of orphan drugs: a scoping review

This study aimed to identify different criteria for priority setting of rare diseases to help policy makers in making evidence-informed decisions.

A scoping review was conducted to comprehensively examine the existing various methods and criteria for prioritizing orphan drugs and rare diseases. We performed searching in Scopus, PubMed, Embase, and websites of health technology assessment (HTA) agencies, 2000-21, and data were extracted.

From the 1,580 identified publications, eleven articles were included. Multicriteria decision analysis was the most frequent method (seven out of eleven studies) used for priority setting. The extracted criteria for priority setting of orphan products were analyzed based on six main categories as follows: health outcomes and clinical implications (six subsets which showed clinical implications), economic aspects (four subsets that indicated the economic effects of orphan drugs and rare diseases), disease and population characteristics (six subsets that included the characteristics of the rare diseases), therapeutic alternatives and uniqueness of orphan technologies (two subsets which discussed the alternatives and uniqueness of orphan technologies), evidence (three subsets which regarded the quality and availability of evidence), and other criteria (three subsets dealing with social and organizational criteria). Cost-effectiveness, budget impact, and disease severity were the most frequent criteria in the studies.

Because of the high price of orphan drugs and limitations of using HTA for reimbursement of them, it is critical to explore them by precise technical methods like multiple criteria decision making in priority setting.