Pathogenic mechanisms and novel experimental anti-inflammatory therapies in hemophilic arthropathy

Hemophilic arthropathy (HA) is a chronic, progressive, and debilitating joint disorder resulting from recurrent hemarthroses in individuals with hemophilia. Despite major advances in prophylactic clotting factor replacement and the introduction of non-factor therapies that have markedly reduced bleeding frequency, HA remains a significant unmet clinical challenge. Accumulating evidence indicates that synovial inflammation is a key driver of HA progression, promoting synovial hyperplasia, macrophage infiltration, pathological angiogenesis, and cartilage destruction. Consequently, anti-inflammatory interventions have emerged as a promising strategy to prevent or limit joint deterioration following bleeding episodes. Recent preclinical studies have focused on targeting inflammatory pathways activated after joint bleeding, including cytokine- and immune cell-mediated signaling networks. These investigations have identified several therapeutic targets that can attenuate disease progression, although their efficacy has been variable and often limited by the complexity of HA pathogenesis. More recently, limited preclinical studies suggest that extracellular vesicles (EVs) exhibit promising therapeutic potential in attenuating the progression of HA in experimental murine models by simultaneously modulating multiple pathological processes, including inflammation, angiogenesis, vascular dysfunction, and cartilage degeneration. Unlike therapies directed against a single inflammatory mediator, EVs possess pleiotropic biological activities and can be engineered to enhance therapeutic efficacy and tissue targeting. Although anti-inflammatory therapies for HA remain largely in the preclinical stage, growing evidence supports their translation potential. Continued advances in EV biology, cargo engineering, manufacturing, and delivery technologies may establish EV-based therapeutics as a novel and effective adjunct to current treatment strategies for preventing or slowing HA progression.