OBJECTIVES: To compare all-cause and knee osteoarthritis (KOA)-related costs associated with procedures and visits of newly-diagnosed KOA patients treated with multi-injection IA-HAs (Intra-articular hyaluronic acid) in real-world practice.

METHODS: A retrospective analysis of Merative MarketScan Research Database (1/1/2015 - 12/31/2019) was conducted to identify newly-diagnosed KOA patients ≥18 years old with ≥1 medical claim of multi-injection IA-HAs: 1% sodium hyaluronate (Euflexxa), hyaluronan (Orthovisc), sodium hyaluronate (Hyalgan) and sodium hyaluronate (Supartz FX) within 1/1/2016 – 12/31/2019, after a 12-month wash-out period. Continuous enrollment for at least 12 months after the first IA-HA claim is required. Total per patient per year (PPPY) all-cause costs and KOA-related total (medical + pharmacy) costs of the Euflexxa treated patient group within the 12-month follow-up were compared to that of the Orthovisc and Hyalgan/Supartz FX (same J-code) group. Costs include inpatient, ER, office, outpatient and others. A doubly robust method with generalized linear models (GLMs) and IPTW (inverse probability treatment weighting) was used. Covariates include age, gender, comorbidities, medication and intervention usage, treatment completion rate and number of injections in the initial IA-HA course.

RESULTS: A total of 1,210,341 eligible KOA patients were identified. The Euflexxa group had 11,207 patients, Orthovisc had 10,235, and Hyalgan/Supartz FX had 8,483. The Euflexxa group had a 6.7% (p < 0.0001) and 4.0% (p < 0.0001) lower mean all-cause and KOA-related total (medical + pharmacy) costs respectively compared to the Orthovisc group, and a 0.9% (p = 0.0016) and 5.0% (p < 0.0001) reduction in mean all-cause cost and KOA-related total (medical + pharmacy) costs respectively compared to that of the Hyalgan/Supartz FX group.

CONCLUSIONS: KOA patients treated with Euflexxa is associated with statistically significant lower KOA-related costs compared to that of Orthovisc or Hyalgan/Supartz FX. More research on treatment associated cost is warranted to potentially lower cost of patient care.