Skeletal formula
Space-filling model of fanapanel as an anion
Clinical data
ATC code
  • None
  • {[7-(4-Morpholinyl)-2,3-dioxo-6-(trifluoromethyl)-3,4-dihydro-1(2H)-quinoxalinyl]methyl}phosphonic acid
CAS Number
PubChem CID
CompTox Dashboard (EPA)
Chemical and physical data
Molar mass409.258 g·mol−1
3D model (JSmol)
  • c1c(c(cc2c1[nH]c(=O)c(=O)n2CP(=O)(O)O)N3CCOCC3)C(F)(F)F
  • InChI=1S/C14H15F3N3O6P/c15-14(16,17)8-5-9-11(6-10(8)19-1-3-26-4-2-19)20(7-27(23,24)25)13(22)12(21)18-9/h5-6H,1-4,7H2,(H,18,21)(H2,23,24,25)

Fanapanel (INN, code name ZK-200775), also known as MPQX, is a quinoxalinedione derivative drug which acts as a competitive antagonist of the AMPA receptor.[1] It was under development by Schering AG for the treatment of cerebral ischemia associated with stroke and trauma, but clinical trials were halted for safety reasons related to possible glial cell toxicity and due to intolerable side effects such as excessive sedation, reduction in consciousness (consisting of stupor and coma), and transient neurological deterioration.[2][3] The drug was also observed to produce visual alteration and impairment, including blurred vision, strongly impaired color perception, and reduced visual acuity and dark vision, side effects thought to be caused by blockade of AMPA receptors in the retina.[4]


  1. ^ Turski L, Huth A, Sheardown M, McDonald F, Neuhaus R, Schneider HH, et al. (September 1998). "ZK200775: a phosphonate quinoxalinedione AMPA antagonist for neuroprotection in stroke and trauma". Proceedings of the National Academy of Sciences of the United States of America. 95 (18): 10960–10965. Bibcode:1998PNAS...9510960T. doi:10.1073/pnas.95.18.10960. PMC 28003. PMID 9724812.
  2. ^ Walters MR, Kaste M, Lees KR, Diener HC, Hommel M, De Keyser J, et al. (2005). "The AMPA antagonist ZK 200775 in patients with acute ischaemic stroke: a double-blind, multicentre, placebo-controlled safety and tolerability study". Cerebrovascular Diseases. 20 (5): 304–309. doi:10.1159/000087929. PMID 16131799. S2CID 25034903.
  3. ^ Elting JW, Sulter GA, Kaste M, Lees KR, Diener HC, Hommel M, et al. (December 2002). "AMPA antagonist ZK200775 in patients with acute ischemic stroke: possible glial cell toxicity detected by monitoring of S-100B serum levels". Stroke. 33 (12): 2813–2818. doi:10.1161/01.str.0000043823.37955.fb. PMID 12468775.
  4. ^ Bergholz R, Staks T, Rüther K (August 2010). "Effects of the AMPA antagonist ZK 200775 on visual function: a randomized controlled trial". PLOS ONE. 5 (8): e12111. Bibcode:2010PLoSO...512111B. doi:10.1371/journal.pone.0012111. PMC 2920815. PMID 20711429.