Analysis of the Health and Budgetary Impact of Chondroitin Sulfate Prescription in the Treatment of Knee Osteoarthritis Compared to NSAIDs and COXIBs.

Background Chondroitin sulfate, alone or associated with glucosamine (CS), is an effective treatment of osteoarthritis, better tolerated than non-steroidal anti-inflammatory drugs (NSAIDs) and cyclooxygenase 2 inhibitors (COXIBs) at gastrointestinal, cardiovascular and renal levels. Objective To estimate the health impact (toxicity by NSAIDs/COXIBs avoided with CS with or without glucosamine) and economic impact (savings due to avoided toxicities) of treatment of knee osteoarthritis with CS compared to NSAIDs/COXIBs, as a consequence of the avoidance of mild-moderate or severe gastrointestinal adverse effects (GIAE), ischaemic heart disease (IHD), acute kidney insufficiency (AKI) and chronic kidney failure (CKF). Methods We compared the current situation (available reimbursed prescription with CS) with a hypothetical situation without CS (treatment only with NSAIDs/COXIBs). The frequency of GIAE, IHD, AKI and CKF with CS and NSAIDs/COXIBs was obtained from published ad hoc studies. The cost of AE management and of the drugs (180 days of treatment) was obtained from Spanish sources. A probabilistic economic model was made for a 3-year period, both at national (NHS) and regional levels. Sensitivity analyses were performed for different durations of treatment (90 and 240 days). Results In Spain, it is estimated that 519,130, 513,616 and 507,377 patients with knee osteoarthritis will be treated with NSAIDs/COXIBs and 112,775, 114,963 and 117,262 with CS in 2020, 2021 and 2022, respectively. Due to better CS tolerability, 55,098 mild-moderate GIAE, 3060 severe GIAE, 204 IHD, 1089 AKI and 733 CKF would be avoided in 3 years. Discounting the cost of the drugs, the three-year savings for the NHS would be 21.8 (12.7-29.5) million euros. Conclusion Due to its better tolerability profile, CS treatment is expected to prevent thousands of AEs over the next 3 years, some of which may be life-threatening for patients, while generating considerable savings for the NHS.