Tomelukast (previously known as LY171883), an orally active antagonist of the CysLT1 receptor (leukotriene D4), which was investigated to treat asthma, but this study was discontinued because of adverse gastrointestinal effect.

Etoxadrol is an NMDA receptor antagonist. It exerts phencyclidine-like properties. Etoxadrol has anticonvulsant and anesthetic activity. Intravenous etoxadrol was clinically tested as an anesthetic.

CE-224535 is a potent, highly selective, orally bioavailable, non-competitive antagonist of the human P2X7 receptor. Pre-clinical pharmacokinetic studies with CE-224535 indicate limited CNS penetration. In clinical trials, CE-224535 failed to demonstrate efficacy in a 2-week study of knee pain in osteoarthritis or a 12-week study in patients with rheumatoid arthritis. CE-224535 is safe and well tolerated after administration of up to 1600 mg as a single dose or 600 mg every 12 hours for 14 days in healthy subjects and 500 mg every 12 hours for 2 weeks in subjects with osteoarthritis of the knee and 12 weeks in rheumatoid arthritis patients with an inadequate response to methotrexate.

Dexoxadrol is a sigma receptor agonist. Dexoxadrol, the D-isomer of dioxodrol, which produces PCP-like behavioural effects and displaces bound [3H]PCP, was a potent blocker of the PCP-sensitive, voltage-gated K+ channel. Dexoxadrol was developed as analgesics for use in humans, however, severe side effects including psychotomimetic effects, unpleasant dreams and aberrations stopped the clinical evaluation of dexoxadrol. Dexoxadrol is a NMDA receptor antagonist, which possesses high affinity to the phencyclidine binding site within the NMDA receptor associated ion channel.

Acedapsone (4,4′-diacetyldiaminodiphenyl sulfone) is a long-acting intramuscular repository derivative of dapsone. Acedapsone is mainly used as a depot leprostatic agent. The parent compound possesses little activity against M. leprae but is metabolized into active dapsone. Its half-life is 46 days, and that of the derived dapsone is 43 days. A 300-mg intramuscular dose maintains dapsone levels in volunteers above the inhibitory concentration for M. leprae for approximately 100 days. Microbiologic and clinical responses are somewhat slower than those for daily dapsone are. Long-term studies with acedapsone by injection five times yearly have yielded encouraging results. Acedapsone shows promise especially in regions where, or in patients in whom, long-term oral therapy is not practical.

INCB-8761 (PF-4136309) is an orally available human chemokine receptor 2 (CCR2) antagonist with potential immunomodulating and antineoplastic activities. Upon oral administration, CCR2 antagonist INCB-8761 specifically binds to CCR2 and prevents binding of the endothelium-derived chemokine ligand CLL2 (monocyte chemoattractant protein-1 or MCP1) to its receptor CCR2, which may result in inhibition of CCR2 activation and signal transduction. This may inhibit inflammatory processes as well as angiogenesis, tumor cell migration, and tumor cell proliferation. INCB-8761 is a potent CCR2 antagonist with high selectivity, weak hERG activity, high free fraction in protein binding, and an excellent in vitro and in vivo ADMET (ADME and toxicology) profile. INCB-8761 entered human clinical trials. It is in phase I/II clinical trials for pancreatic cancer.

Etiocholanedione is a natural metabolite of dehydroepiandrosterone with potent antiobesity activity. Etiocholanedione has been identified as a metabolite of an altered androgen metabolism that eventually leads hepatocellular carcinoma to impaired hormone responsiveness in human. Etiocholanedione has been identified as a metabolite of 17alpha-hydroxyprogesterone in some patients affected by congenital adrenal hyperplasia, although it doesn't appear to account for the masculinization observed in congenital hyperplasia.

PD123319 is a potent, selective AT2 angiotensin II receptor antagonist with IC50 of 34 nM.PD123319 had been in phase I clinical trials by Pfizer for the treatment of hypertension. However, this research has been discontinued.