Clinical data
Trade namesBaynas
AHFS/Drugs.comInternational Drug Names
Routes of
Oral (tablets)
ATC code
  • None
Legal status
Legal status
  • Rx-only (JP)
  • 3-((3R)-3-{[(4-fluorophenyl)sulfonyl]amino}-1,2,3,4-tetrahydro-9H-carbazol-9-yl)propanoic acid
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.159.668 Edit this at Wikidata
Chemical and physical data
Molar mass416.47 g·mol−1
3D model (JSmol)
  • C1CC2=C(CC1NS(=O)(=O)C3=CC=C(C=C3)F)C4=CC=CC=C4N2CCC(=O)O
  • InChI=1S/C21H21FN2O4S/c22-14-5-8-16(9-6-14)29(27,28)23-15-7-10-20-18(13-15)17-3-1-2-4-19(17)24(20)12-11-21(25)26/h1-6,8-9,15,23H,7,10-13H2,(H,25,26)/t15-/m1/s1

Ramatroban (INN) (also known as BAY u3405)[1] is a thromboxane receptor antagonist.[2]

It is also a DP2 receptor antagonist.[3]

It is indicated for the treatment of coronary artery disease.[4] It has also been used for the treatment of asthma.[5]

It has been suggested that ramatroban, by modulating DP2 receptor, can reverse viremia-associated proinflammatory and prothrombotic processes which are similar to those induced by SARS-Cov-2.[citation needed] Hence, ramatroban, that has been used for the treatment of allergic rhinitis in Japan for the past two decades with a well established safety profile, merits investigation as a novel immunotherapy for the treatment of COVID-19 disease, although no clinical trial has yet been conducted.[6]

Ramatroban was developed by the German pharmaceutical company Bayer AG and is co-marketed in Japan by Bayer Yakuhin then marketed by Kyorin Pharmaceutical and Nippon Shinyaku Co., Ltd. under the trade name Baynas.


  1. ^ "Ramatroban (compound)". PubChem. National Center for Biotechnology Information. Retrieved 22 June 2019.
  2. ^ Sugimoto H, Shichijo M, Iino T, Manabe Y, Watanabe A, Shimazaki M, et al. (April 2003). "An orally bioavailable small molecule antagonist of CRTH2, ramatroban (BAY u3405), inhibits prostaglandin D2-induced eosinophil migration in vitro". The Journal of Pharmacology and Experimental Therapeutics. 305 (1): 347–352. doi:10.1124/jpet.102.046748. PMID 12649388. S2CID 10016709.
  3. ^ Royer JF, Schratl P, Carrillo JJ, Jupp R, Barker J, Weyman-Jones C, et al. (September 2008). "A novel antagonist of prostaglandin D2 blocks the locomotion of eosinophils and basophils". European Journal of Clinical Investigation. 38 (9): 663–671. doi:10.1111/j.1365-2362.2008.01989.x. PMID 18837743.
  4. ^ Fiedler VB, Seuter F, Perzborn E (December 1990). "Effects of the novel thromboxane antagonist Bay U 3405 on experimental coronary artery disease" (PDF). Stroke. 21 (12 Suppl): IV149–IV151. PMID 2260140.
  5. ^ Endo S, Akiyama K (November 1996). "[Thromboxane A2 receptor antagonist in asthma therapy]". Nihon Rinsho. Japanese Journal of Clinical Medicine (in Japanese). 54 (11): 3045–3048. PMID 8950952.
  6. ^ Rizk JG, Kalantar-Zadeh K, Mehra MR, Lavie CJ, Rizk Y, Forthal DN (September 2020). "Pharmaco-Immunomodulatory Therapy in COVID-19". Drugs. 80 (13): 1267–1292. doi:10.1007/s40265-020-01367-z. PMC 7372203. PMID 32696108.