Norlevorphanol is the levo-isomer of 3-hydroxymorphinan (morphinan-3-ol). It is is an opioid analgesic of the morphinan family. Norlevorphanol is a Schedule I controlled substance (opiate).

Elbimilast or ronomilast (previously ELB 353) is a phosphodiesterase IV (PDE4) inhibitor. It has been investigated in the treatment of chronic obstructive pulmonary disease.

Icopezil (previously known as CP-118,954) was developed as a selective acetylcholinesterase inhibitor for the treatment of cognitive disorders. Phase II trials of icopezil were underway in Japan and in the USA for the treatment of patients with Alzheimer's disease. However, Pfizer has discontinued these studies.

Talampanel (TLP) was developed as a noncompetitive (allosteric) antagonist of the AMPA receptor. Talampanel does not act directly on the AMPA receptor, but at an allosteric site referred to as the GYKI receptor. Talampanel is being studied in the treatment of brain tumors and other brain disorders, such as epilepsy, Parkinson disease, amyotrophic lateral sclerosis, dyskinesias, glioblastoma, multiple sclerosis. It is a type of AMPA receptor antagonist. Dizziness has been the most commonly reported adverse event, with some sedation and ataxia, drowsiness and headaches reported at higher doses.

Midesteine (previously known as MR 889), a thiolactic acid derivative was developed as an inhibitor of the chymotrypsin and elastolytic activity of leukocyte elastase. Midesteine participated in clinical trials for patients with chronic obstructive pulmonary disease. The drug is also studied to treat asthma, cystic fibrosis, and emphysema. However, all these studies were discontinued.

Procaspase-activating compound 1, PAC-1, has been introduced as a direct activator of procaspase-3 and has been suggested as a therapeutic agent against cancer. Its activation of procaspase-3 is dependent on the chelation of zinc. In 2015, a phase I clinical trial of PAC-1 opened for enrollment of cancer patients, and in 2016, it was announced that PAC-1 had been granted Orphan Drug Designation for treatment of glioblastoma by the FDA.

8-chloroadenosine (8-Cl-Ado) is a ribonucleoside analog. The mechanism of its action remains poorly understood, however, it is known that the drug inhibits RNA synthesis. It has significant cytotoxic activity against lymphoid and myeloid malignant cells. The nucleoside analog 8-Cl-Ado is phosphorylated into its cytotoxic triphosphate 8-Cl-ATP. The accumulation of the cytotoxic metabolite results in a parallel decrease of the ATP cellular pools. 8-Cl-Ado gets incorporated into RNA during transcription, hindering this process. In addition, this triphosphate inhibits ATP-dependent poly(A) tail synthesis, and, as a consequence, mRNA processing is inhibited, resulting in vitro cytotoxicity in several solid and hematological malignancies. This agent is currently in clinical trials for the treatment of chronic lymphocytic leukemia and acute myeloid leukemia.

Artemisone (also known as BAY-44-9585; BAY-449585) is a 10-amino-artemisinin derivative that is markedly superior in vitro and in vivo to current artemisinins against malaria and also possesses antitumor activity. Nonetheless, its low water solubility and bioavailability has limited its clinical use, that is why was studied the encapsulated artemisone against human melanoma A-375. In addition, artemisone has the potential to be efficacious for the treatment of H. pylori infection, especially in combination with antibiotics.

Carotegrast is phenylalanine derivative patented by pharmaceutical company Ajinomoto Co. for the treatment or prevention of inflammatory disease states related to the α4 integrin-dependent adhesion process. In preclinical studies, Carotegrast shows pharmacological activity in rheumatoid arthritis and inflammatory bowel disease.

Y-700 (Niraxostat or 1-[3-Cyano-4-(2,2-dimethylpropoxy)phenyl]-1H-pyrazole-4-carboxylic acid) is an inhibitor of xanthine oxidoreductase. Y-700 demonstrated high oral bioavailability being predominantly eliminated via the liver. It potently reduces serum uric acid levels. Y-700 was in clinical trials for the treatment of gout.