Perspective: Mesenchymal stromal cells and PRP in osteoarthritis: Hope, hype and the hard evidence.

In the absence of approved disease-modifying therapies for osteoarthritis (OA), regenerative therapies have emerged as promising interventions that have attracted considerable enthusiasm among patients, clinicians, and researchers. This interest has been particularly prominent in knee OA, where intra-articular orthobiologic interventions are most commonly studied and clinically adopted. However, the broad concept of "regeneration" encompasses a diverse range of interventions, including mesenchymal stromal cells (MSCs), platelet-rich plasma (PRP), and other orthobiologic products, which differ substantially in their biological rationale and supporting evidence. Despite increasing clinical adoption, the evidence underpinning these therapies has not kept pace with expectations. In this perspective, we examine regenerative therapies for osteoarthritis through the lens of hope, hard evidence, and hype. By critically evaluating the current clinical evidence and exploring how commercialisation and media narratives have shaped expectations and accelerated clinical adoption, we argue that a more balanced view of regenerative therapies is warranted until robust evidence from well-designed phase 3 trials becomes available.