Orphan Drugs and Diseases: A Systematic Review.

Rare diseases, though individually infrequent, collectively affect over 300 million people worldwide. The development of orphan drugs to treat these conditions is hampered by regulatory inconsistencies, high costs, and limited clinical trial populations. To systematically review the current landscape of orphan drugs and rare diseases, focusing on definitions, therapeutic approaches, health economic evaluations, and stakeholder perspectives. A systematic review was conducted using 70 reference-screened articles, out of which 10 were selected based on relevance to rare diseases or orphan drug policy, economics, or clinical management. Study types included systematic and scoping reviews, observational studies, and health economic evaluations. Data extraction focused on definitions, healthcare roles, cost analyses, and clinical outcomes. Definitions of rare diseases varied globally, impacting drug approval processes. Economic evaluations revealed disparities in funding orphan drugs. Studies emphasized the growing role of pharmacists and stakeholders in therapeutic access. High-cost burdens, ethical considerations, and diagnostic advancements were recurring themes. Pediatric and syndromic rare conditions, like Duchenne muscular dystrophy and Turner syndrome, were notably covered. Effective rare disease care requires harmonized definitions, ethical pricing models, interdisciplinary healthcare roles, and evidence-based policies to ensure equitable access and sustainability.