Loxoprofen: A Review in Pain and Inflammation

Abstract

Loxoprofen (Loxonin(®), Loxonin(®) Pap, Loxonin(®) Tape) is a prodrug-type NSAID that is available in several formulations, including 60 mg tablets, 100 mg hydrogel patches and 50 or 100 mg tape. In active comparator-controlled trials, oral loxoprofen therapy (ranging from 2 days to 6 weeks' duration depending on the pain type) provided analgesic efficacy that generally did not significantly differ from that of celecoxib for postoperative pain or frozen shoulder, ibuprofen for knee osteoarthritis or naproxen for lumbar pain. In double-blind, double-dummy, multicentre trials, loxoprofen hydrogel patches were noninferior to oral loxoprofen with regard to rates of final overall symptomatic improvement over 1-4 weeks in patients with knee osteoarthritis, myalgia or trauma-induced swelling and pain. Loxoprofen hydrogel patches were also noninferior to other commercially available patches (ketoprofen and indometacin) over 2 or 4 weeks in patients with knee osteoarthritis or myalgia in open-label studies. Oral and topical loxoprofen were generally well tolerated in clinical trials. Thus, loxoprofen is a useful analgesic option for patients with pain and inflammation, with topical loxoprofen potentially reducing the risk of gastrointestinal, cardiovascular and renal complications associated with oral NSAID use.

Identification of sulfonyl‐loxoprofen as novel phase 2 conjugate in rat

“…In a previous metabolomic study of loxoprofen, three hydroxylated metabolites were detected in urine after oral administration in rats, mice, dogs, and monkeys (Tanaka et al, ). It has previously been stated that loxoprofen is not a substrate of CYP enzymes (Greig & Garnock‐Jones, ), but we identified CYP3A4 and CYP3A5 as being involved in the hydroxylation of loxoprofen (Shrestha et al, ). Cytochrome P450 (CYP) is a major enzyme involved in oxidative metabolism in xenobiotics.…”

“…In a previous metabolomic study of loxoprofen, three hydroxylated metabolites were detected in urine after oral administration in rats, mice, dogs, and monkeys (Tanaka et al, 1983). It has previously been stated that loxoprofen is not a substrate of CYP enzymes (Greig & Garnock-Jones, 2016), but † These authors equally contributed to the study.…”

Evaluation of the Percutaneous Absorption of Drug Molecules in Zebrafish

“…We obtained results that are inconsistent with those observed in human skin regarding LSH and TH. LSH is a nonsteroidal anti-inflammatory drug that can be absorbed by human skin [ 32 ]. However, we did not detect it in the blood of zebrafish after exposure and transdermal administrations, even with a high dose.…”

Preparative enantioseparation of loxoprofen precursor by recycling countercurrent chromatography with hydroxypropyl‐β‐cyclodextrin as a chiral selector

“…Loxoprofen, sodium (±)-2-[4-(2-oxocyclopentylmethyl)phenyl]propionate dihydrate, is a nonsteroidal anti-inflammatory drug, used in the treatment for pain and inflammation associated with chronic conditions and relief for headache, fever, toothache, and back pain [1]. Loxoprofen sodium is generally oral-administered as an equal parts mixture of four steroisomers since it owns two chiral carbons, as shown in Figure 1.…”