Diclofenac etalhyaluronate (DF-HA)

Diclofenac etalhyaluronate (DF-HA), also known as ONO-5704 or SI-613, is a pharmaceutical conjugate where the non-steroidal anti-inflammatory drug (NSAID) diclofenac is covalently linked to a hyaluronic acid (HA) polymer [2, 4]. It is not a biological target but a therapeutic agent designed for the treatment of osteoarthritis and other musculoskeletal disorders [3, 5]. The molecule functions as a sustained-release system; upon intra-articular injection, the ester linkage is hydrolyzed to release diclofenac, which inhibits cyclooxygenase enzymes (COX-1 and COX-2), thereby reducing prostaglandin synthesis and alleviating pain and inflammation [1, 2]. Concurrently, the HA component improves joint lubrication and viscoelasticity, addressing the biomechanical aspects of joint disease [1, 4]. This conjugate aims to provide prolonged local efficacy while minimizing systemic exposure and the associated gastrointestinal or cardiovascular side effects of oral NSAIDs [4, 10]. Clinical trials have demonstrated significant pain reduction in patients with knee and hip osteoarthritis, although safety monitoring is required due to reports of anaphylactic reactions [7]. The hyaluronic acid moiety may also interact with CD44 receptors on synoviocytes, potentially enhancing the localization of the drug within the joint space [11, 14].

Other names

Diclofenac-hyaluronate conjugateDiclofenac etalhyaluronate sodiumONO-5704SI-613Joycle

Diclofenac etalhyaluronate acts as a prodrug that releases diclofenac to inhibit cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) enzymes, reducing prostaglandin synthesis [1, 2]. The hyaluronic acid component provides joint lubrication and may facilitate targeted delivery via the CD44 receptor [11, 14].