Amelubant, its metabolite BIIL 260 (formed by removal of the ethoxycarbonyl protecting group), and its major metabolite BIIL 315 (formed by removal of the protecting group and glucuronidation) had potent in vitro and in vivo Leukotriene B4 receptor antagonistic properties. Amelubant has been in phase II clinical trials by Boehringer Ingelheim for the treatment of cystic fibrosis, chronic obstructive pulmonay disease, bronchial asthma and rheumatoid arthritis. However, this research has been discontinued. In 2002, orphan drug designation was received in E.U. for the treatment of cystic fibrosis. Serious adverse events of Amelubant were characterized by increased presentation of respiratory signs and/or symptoms associated with pulmonary exacerbation and resulted in admission to a hospital and/or administration of IV antibiotics.

Romazarit, (Ro 31-3948, 7), 2-[[2-(4-chlorophenyl)-4-methyl-5-oxazolyl]methoxy]-2-methylpropionic acid is a substituted heterocyclic alkoxypropionic acid. Romazarit was considered to be a potential disease-modifying antirheumatic drug. Romazarit was withdrawn due to its toxicity profile.

Bindarit (2-Methyl-2-[[1-(phenylmethyl)-1H-indazol-3yl]methoxy]propanoic acid; AF-2838) is an indazolic derivative that is devoid of any immunosuppressive effects and has no effect on arachidonic acid metabolism. It has been proved to have anti-inflammatory activity in a number of experimental diseases, including pancreatitis, arthritis, and lupus nephritis. This therapeutic effect has been associated with its ability to interfere selectively with monocyte recruitment, although the underlying molecular mechanisms are unknown. Bindarit selectively inhibits the production of the monocyte chemotactic protein subfamily of CC inflammatory chemokines (MCP-1/CCL2, MCP-3/CCL7, MCP-2/CCL8) without affecting the production of the cytokines IL-1, IL-6, or the chemokines IL-8, MIP-1α.

Actarit (MS-932) is an anti-inflammatory drug developed in Japan for use in rheumatoid arthritis (RA). Actarit suppresses adjuvant arthritis through modulation of the immune system. Actarit acts on RA synovial cells to reduce cell-cell interactions with autologous synovium infiltrating lymphocytes and to inhibit proinflammatory cytokine and MMP production, leading to amelioration of symptoms of RA.