Biochem/Physiol Actions | Rofecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, is classified as a nonsteroidal anti-inflammatory drug (NSAID). Unlike celecoxib, rofecoxib lacks a sulfonamide chain and does not require CYP450 enzymes for metabolism. Like other NSAIDs, rofecoxib exhibits anti-inflammatory, analgesic, and antipyretic activity. NSAIDs appear to inhibit prostaglandin synthesis via the inhibition of cyclooxygenase (COX), which are responsible for catalyzing the formation of prostaglandins in the arachidonic acid pathyway. There are at least two isoenzymes, COX-1 and COX-2, that have been identified. Although the exact mechanisms have not been clearly established, NSAIDs exert their anti-inflammatory, analgesic, and antipyretic primarily through the inhibition of COX-2. The inhibition of COX-1 is principally responsible for the negative effects on the GI mucosa. As rofecoxib is selective for COX-2, it may be potentially associated with a decreased risk of certain adverse events, but more data is needed to fully evaulate the drug. Rofecoxib is a synthetic, nonsteroidal derivative of phenyl-furanone with antiinflammatory, antipyretic and analgesic properties and potential antineoplastic properties. Rofecoxib binds to and inhibits the enzyme cyclooxygenase-2 (COX-2), resulting in an inhibition of the conversion of arachidonic acid to prostaglandins. COX-related metabolic pathways may represent key regulators of cell proliferation and neo-angiogenesis. Some epithelial tumor cell types overexpress pro-angiogenic COX-2. |
