PF-04457845 structure.png
Clinical data
ATC code
  • None
Legal status
Legal status
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass455.441 g·mol−1
3D model (JSmol)

PF-04457845 is a potent and exquisitely selective inhibitor of the enzyme fatty acid amide hydrolase (FAAH), with an IC50 of 7.2nM, and both analgesic and antiinflammatory effects in animal studies comparable to naproxen.[1]

It has been well tolerated in human trials even at high dose ranges with no evidence for cognitive dysfunction, and has completed Phase II clinical trials for the treatment of osteoarthritis,[1][2][3][4] but was found to be ineffective.[5]

See also[edit]


  1. ^ a b Johnson DS, Stiff C, Lazerwith SE, Kesten SR, Fay LK, Morris M, et al. (February 2011). "Discovery of PF-04457845: A Highly Potent, Orally Bioavailable, and Selective Urea FAAH Inhibitor". ACS Medicinal Chemistry Letters. 2 (2): 91–96. doi:10.1021/ml100190t. PMC 3109749. PMID 21666860.
  2. ^ Ahn K, Smith SE, Liimatta MB, Beidler D, Sadagopan N, Dudley DT, et al. (July 2011). "Mechanistic and pharmacological characterization of PF-04457845: a highly potent and selective fatty acid amide hydrolase inhibitor that reduces inflammatory and noninflammatory pain". The Journal of Pharmacology and Experimental Therapeutics. 338 (1): 114–24. doi:10.1124/jpet.111.180257. PMC 3126636. PMID 21505060.
  3. ^ Li GL, Winter H, Arends R, Jay GW, Le V, Young T, Huggins JP (May 2012). "Assessment of the pharmacology and tolerability of PF-04457845, an irreversible inhibitor of fatty acid amide hydrolase-1, in healthy subjects". British Journal of Clinical Pharmacology. 73 (5): 706–16. doi:10.1111/j.1365-2125.2011.04137.x. PMC 3403198. PMID 22044402.
  4. ^ Clinical trial number NCT00981357 for "A Study To Investigate Whether PF-04457845 Is Effective In Treating Pain, Is Safe And Tolerable In Patients With Osteoarthritis Of The Knee" at
  5. ^ Huggins JP, Smart TS, Langman S, Taylor L, Young T (September 2012). "An efficient randomised, placebo-controlled clinical trial with the irreversible fatty acid amide hydrolase-1 inhibitor PF-04457845, which modulates endocannabinoids but fails to induce effective analgesia in patients with pain due to osteoarthritis of the knee". Pain. 153 (9): 1837–46. doi:10.1016/j.pain.2012.04.020. PMID 22727500.