Novel poly(lactic-co-glycolic acid) nanoliposome-encapsulated diclofenac sodium and celecoxib enable long-lasting synergistic treatment of osteoarthritis.

Background: Diclofenac sodium (DS) and celecoxib (CEL) are primary anti-inflammatory agents used in the treatment of osteoarthritis (OA). Formulating these drugs into extended-release versions can effectively address the issue of multiple daily doses. In this study, we designed and synthesized a novel poly(lactic-co-glycolic acid) (PLGA) nanoliposome as a dual-drug delivery sustained-release formulation (PPLs-DS-CEL) to achieve long-lasting synergistic treatment of OA with both DS and CEL.

Methods: PPLs-DS-CEL was synthesized by the reverse evaporation method and evaluated for its physicochemical properties, encapsulation efficiency, drug release kinetics and biological properties. A rat OA model was established to assess the therapeutic efficacy and biosafety of PPLs-DS-CEL.

Results: The particle size of PPLs-DS-CEL was 218.36 ± 6.27 nm, with a potential of 32.56 ± 3.28 mv, indicating a homogeneous vesicle size. The encapsulation of DS and CEL by PPLs-DS-CEL was 95.18 ± 4.43% and 93.63 ± 5.11%, with drug loading of 9.56 ± 0.32% and 9.68 ± 0.34%, respectively. PPLs-DS-CEL exhibited low cytotoxicity and hemolysis, and was able to achieve long-lasting synergistic analgesic and anti-inflammatory therapeutic effects in OA through slow release of DS and CEL, demonstrating good biosafety properties.

Conclusion: This study developed a novel sustained-release nanoliposomes formulation capable of co-loading two drugs for the long-acting synergistic treatment of OA. It offers a new and effective therapeutic strategy for OA treatment in the clinic settings and presents a promising approach for drug delivery systems.