Isbufylline is a xanthine derivative. This compound exhibits remarkable antibronchospastic properties both in in vitro and in vivo (after oral or intravenous administration) experimental models. Isbufylline is significantly more effective than theophylline in antagonizing bronchospasms elicited by spasmogens (capsaicin, arachidonic acid, PAF and antigen) which mainly act by a local release of biologically active substances proposed to be involved in the pathogenesis of asthma. Isbufylline, unlike theophylline, possesses little or no CNS excitatory properties. Isbufylline exerts a greater inhibitory activity than theophylline on total phosphodiesterase activity in the rat lung.

Peliglitazar (also known as BMS 426707-01), a dual α/γ peroxisome proliferator-activated receptor agonist, has been studied in phase I/II clinical trial in patients with type 2 diabetes mellitus. However, this study was discontinued.

Cyclobutoic acid is a synthetic analog of mevalonic acid, developed by the Italian company Farmitalia Carlo Erba SPA. The compound inhibited the incorporation of [14C] into CO2, fatty acids and cholesterol, and was used for the treatment of hepatic deficiency.

Bicifadine (DOV-220075) is not a narcotic and is well-tolerated and, in preclinical studies, has been shown not to act at any opiate receptor, but inhibits monoamine neurotransmitter uptake by recombinant human transporters in vitro with a relative potency of norepinephrine:serotonin:dopamine of 1:2:17. Bicifadine was in Phase II clinical trial for pain caused by diabetic neuropathy, in addition, was in phase III clinical trial to treat Chronic Low Back Pain, but that studies were discontinued

Sulfaloxic acid is a benzamide derivative patented by Chemische Fabrik von Heyden A.-G. as an antibacterial agent.

Tiomolibdic acid salt, Bis-choline tetrathiomolybdate (ATN-224, WTX-101), is under investigation as a therapy against different cancers and Wilson’s disease (WD). ATN-224 is a second-generation analog of ammonium tetrathiomolybdate. ATN-224 is a novel copper chelator. ATN-224 inhibits CuZn superoxide dismutase 1 (SOD1) leading to antiangiogenic and antitumor effects. Strategically tailoring combination regimens that include ATN-224 and target ROS may be a viable approach to advance the treatment of melanoma. ATN-224 is in phase III clinical trial for the treatment of Hepatolenticular degeneration. WTX-101 is in phase II clinical trials for the treatment of Wilson's disease. Once daily WTX-101 treatment over 24 weeks improved neurologic disease, hepatic status and copper control in newly diagnosed WD patients. WTX-101 appears well tolerated. Drug-induced, paradoxical, neurological deterioration was not observed. This compound has received orphan drug designation in both the United States and the European Union. WTX-101 was originally discovered by University of Michigan and now is being developed by Wilson Therapeutics by acquisition.

Ursulcholic acid is a soluble form of ursodeoxycholic acid. It is an anticholinergic agent.

Olpadronate, a nitrogenated bisphosphonate that can inhibit bone resorption. Although it shares the therapeutic and pharmacological properties of pamidronate and alendronate, it has a greater dosage amplitude, more predictable effects, and greater digestive tolerability than other bisphosphates. Clinical trials have shown that the oral olpadronate was well tolerated and effective in the treatment of Paget's disease. In addition, the drug is ongoing in phase II clinical trials in the Netherlands. This clinical trial has to assess the efficacy of the intravenous drug in decreasing the average back pain intensity from baseline.

Temelastine (also known as SK&F 93944) is a competitive histamine H1-receptor antagonist, which does not penetrate the central nervous system. This drug was studied as an anti-allergic agent. Experiments on animals have shown that the drug was efficacious vs. pharmacologic and antigen-induced bronchoconstriction.