First U.S. Enrollee in Nexsphere-F RESORB Pivotal Trial: What Sports Medicine Clinicians Should Know

The RESORB pivotal trial has enrolled its first U.S. patient, testing Nexsphere-F as a minimally invasive genicular artery embolization option for symptomatic knee osteoarthritis. According to NEXTBIOMEDICAL PR Newswire release on RESORB trial enrollment, the randomized study will compare Nexsphere-F against intra-articular corticosteroid injection in roughly 126 patients across more than 10 U.S. sites under an IDE.

Nexsphere-F uses fast-resorbable microspheres to temporarily occlude periarticular vessels, dissolving within hours and producing targeted nociceptive disruption that the company links to rapid pain relief. This temporary vascular occlusion plausibly interrupts neurogenic pain signaling in knee osteoarthritis and differs from permanent embolic approaches by allowing vessel reperfusion and limiting longer-term ischemic or tissue-damage risk, which is clinically important when comparing joint-preserving strategies.

JVIR and other real-world reports summarized in the announcement provide the principal clinical signal: an average ~67% pain reduction at 6 months in a 155-patient series, which supports the hypothesis that targeted periarticular embolization can produce substantial symptom relief. Company-reported absence of device-related serious adverse events in these series is encouraging; however, the largely single-arm, observational nature of much real-world data leaves potential for selection and placebo effects, so randomized pivotal data are needed to confirm comparative efficacy and safety.