Approaches to reduce the uncertainty in the clinical efficacy of orphan drugs

Medicinal products (MPs) for treating rare (orphan) diseases are characterized by high uncertainty regarding clinical efficacy. This uncertainty is primarily attributed to the limited number of available and completed clinical trials and inconclusive data on efficacy. The purpose of this review was to describe the main issues related to the characteristics of orphan diseases, including the characteristics of clinical trials of orphan MPs, the orphan medicines themselves, ethical issues, and suggestions for possible solutions to these problems. This review identified and described the main aspects affecting the diagnosis and treatment of rare diseases, development of orphan MPs, and quality of clinical trials. In addition, issues related to quality of life were considered. 

Furthermore, some organizational and clinical solutions were suggested to reduce the uncertainty of the utilization of orphan MPs, allowing for greater clarity in their implementation in practice.

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