licofelone licofelone licofelone is a dual cox/lox inhibitor that was studied in clinical trials as a treatment for osteoarthritis and which was under development by merckle gmbh with partners alfa wassermann and lacer. licofelonelegal statuslegal status investigational identifiers iupac name acetic acid cas number156897-06-2pubchem cid133021chemspider117391 nuniip5t6bys22ychemblchembl52854comptox dashboard (epa)dtxsid40166154 echa infocard100.222.821 chemical and physical dataformulac23h22clno2molar mass379.88 g·mol−1 inchi inchi=1s/c23h22clno2/c1-23(2)13-19-22(15-6-4-3-5-7-15)21(16-8-10-17(24)11-9-16)18(12-20(26)27)25(19)14-23/h3-11h,12-14h2,1-2h3,(h,26,27) nkey:uawxgrjvzsausz-uhfffaoysa-n n ny (what is this?) (verify) licofelone is both an analgesic and an anti-inflammatory. inhibition of 5-lipoxygenase (5-lox) may reduce the gastrointestinal toxicity associated with other nonsteroidal anti-inflammatory drugs (nsaid), which only inhibit cyclooxygenase (cox). licofelone is the first drug to inhibit both. phase iii trials for osteoarthritis were conducted in the early 2000s, but results were mixed and the drug has never been submitted for regulatory approval.