MF63

IC50: 0.9 and 1.3 nM for pig mPGES-1 and human mPGES-1

MF63 is a potent, selective and orally active mPGES-1 inhibitor. Microsomal prostaglandin E synthase-1 (mPGES-1) is a terminal prostaglandin E2 synthase in the cyclooxygenase pathway. Thus, inhibitors of mPGES-1 may block prostaglandin E2 production and relieve inflammatory symptoms.

In vitro: MF63 was found to be significantly more potent than those previously reported mPGES-1 inhibitors with an intrinsic inhibitory potency on the recombinant human mPGES-1 enzyme. Furthermore, MF63 showed a PGE2 whole cell inhibition in A549 cells and a human whole blood activity [1].

In vivo: In rodent species, MF63 inhibited guinea pig mPGES-1 strongly but not the mouse or rat enzyme. When tested in the guinea pig and a knock-in (KI) mouse expressing human mPGES-1, MF63 suppressed the synthesis of PGE2 selectively, but not other prostaglandins that were inhibitable by nonsteroidal anti-inflammatory drugs (NSAID), yet remaided NSAID-like efficacy at inhibiting lipopolysaccharide-induced hyperalgesia, pyresis, and iodoacetate-induced osteoarthritic pain. Additionally, MF63 did not cause NSAID-like gastrointestinal toxic effects, such as mucosal erosions or leakage in the KI mice or nonhuman primates, although MF63 markedly inhibited PGE2 synthesis in the KI mouse stomach [1].

Clinical trial: N/A

Reference:
[1] Xu D,Rowland SE,Clark P,Giroux A,Cté B,Guiral S,Salem M,Ducharme Y,Friesen RW,Méthot N,Mancini J,Audoly L,Riendeau D.  MF63 [2-(6-chloro-1H-phenanthro[9,10-d]imidazol-2-yl)-isophthalonitrile], a selective microsomal prostaglandin E synthase-1 inhibitor, relieves pyresis and pain in preclinical models of inflammation. J Pharmacol Exp Ther.2008 Sep;326(3):754-63.

MF63 [2-(6-chloro-1H-phenanthro[9,10-d]imidazol-2-yl)-isophthalonitrile], a selective microsomal prostaglandin E synthase-1 inhibitor, relieves pyresis and pain in preclinical models of inflammation.[Pubmed:18524979]

J Pharmacol Exp Ther. 2008 Sep;326(3):754-63.

Microsomal prostaglandin E synthase-1 (mPGES-1) is a terminal prostaglandin E(2) (PGE(2)) synthase in the cyclooxygenase pathway. Inhibitors of mPGES-1 may block PGE(2) production and relieve inflammatory symptoms. To test the hypothesis, we evaluated the antipyretic and analgesic properties of a novel and selective mPGES-1 inhibitor, MF63 [2-(6-chloro-1H-phenanthro-[9,10-d]imidazol-2-yl)isophthalonitrile], in animal models of inflammation. MF63 potently inhibited the human mPGES-1 enzyme (IC(50) = 1.3 nM), with a high degree (>1000-fold) of selectivity over other prostanoid synthases. In rodent species, MF63 strongly inhibited guinea pig mPGES-1 (IC(50) = 0.9 nM) but not the mouse or rat enzyme. When tested in the guinea pig and a knock-in (KI) mouse expressing human mPGES-1, the compound selectively suppressed the synthesis of PGE(2), but not other prostaglandins inhibitable by nonsteroidal anti-inflammatory drugs (NSAIDs), yet retained NSAID-like efficacy at inhibiting lipopolysaccharide-induced pyresis, hyperalgesia, and iodoacetate-induced osteoarthritic pain. In addition, MF63 did not cause NSAID-like gastrointestinal toxic effects, such as mucosal erosions or leakage in the KI mice or nonhuman primates, although it markedly inhibited PGE(2) synthesis in the KI mouse stomach. Our data demonstrate that mPGES-1 inhibition leads to effective relief of both pyresis and inflammatory pain in preclinical models of inflammation and may be a useful approach for treating inflammatory diseases.