Description
Meclofenamate is a time-
dependent, non-
specific competitive inhibitor of COX-
1 and -
2. The IC
50 values for inhibition of human recombinant COX-
1 and -
2 are 1.5 and 9.7 μM, respectively for instantaneous inhibition. However, the IC
50 is much lower if pre-
incubated with the enzyme.
1
Originator
Meclomen,Warner Lambert,US,1980
Uses
antiinflammatory, antipyretic
Definition
ChEBI: An organic sodium salt derived from meclofenamic acid. Its monohydrate is used for the treatment of dysmenorrhoea (painful periods), osteoarthritis and rheumatoid arthritis.
Indications
Meclofenamate sodium (Meclomen) is
prescribed for rheumatoid arthritis and osteoarthritis.
The fenamates show no clear superiority in antiinflammatory
activity and may produce more adverse
effects than other NSAIDs.
Manufacturing Process
A mixture consisting of 22.7 g potassium o-bromobenzoate, 16.6 g 2,6- dichloro-3-methylaniline, 12 ml N-ethylmorpholine, 60 ml diethylene glycol dimethyl ether, and 1.0 g anhydrous cupric bromide is heated in a nitrogen atmosphere at 145°C to 155°C for 2 hours. The reaction mixture is diluted with 60 ml diethylene glycol dimethyl ether and acidified with 25 ml concentrated hydrochloric acid. The acidic mixture is diluted with 100 ml of water and the liquid phase decanted from the insoluble oil. The insoluble oil is stirred with methanol and the crystalline N-(2,6-dichloro-3-methylphenyl) anthranilic acid which separates is collected and washed with methanol. The product, after recrystallization from acetone-water mixture, melts at 248°C to 250°C.
Brand name
Meclomen (Parke-Davis).
Therapeutic Function
Antiinflammatory
General Description
Meclofenamate sodium (Meclomen) is available for use inthe treatment of acute and chronic RA, OA, and primarydysmenorrhea. It is metabolized in a similar manner tomefenamic acid discussed above, thus a similar restriction isalso applied to meclofenamate. The most significant side effectsare GI, including diarrhea.
Biological Activity
Dual 5-lipoxygenase (IC50=46.8 μM) and cyclooxygenase I and II inhibitor (IC50=0.6 μM). Clinically useful NSAID.
Pharmacokinetics
Meclofenamate sodium is rapidly and almost completely absorbed following oral administration, reaching peak plasma
levels within 2 hours. It is highly bound to plasma proteins (99%) and has a plasma half-life of 2 to 4 hours.
Metabolism involves oxidation of the methyl group, aromatic hydroxylation, monodehalogenation, and conjugation.
Urinary excretion accounts for approximately 75% of the administered dose. The major metabolite is the product of
3′-methyl oxidation and has been shown to possess anti-inflammatory activity.
Clinical Use
Meclofenamate sodium is indicated for the relief of mild to moderate pain, the acute and chronic treatment of
rheumatoid arthritis and osteoarthritis, the treatment of primary dysmenorrhea, and the treatment of idiopathic, heavy
menstrual blood loss.
