Beloxepin (or ADL6906), a novel dual norepinephrine reuptake inhibitor and serotonin receptor antagonist, was investigated for the treatment of the pain and Major depressive disorder, but these studies were discontinued.

Fananserin is a potential antipsychotic compound with a high affinity for both D4 and 5-HT2A receptors, and negligible affinity for D2 receptors. Fananserin has been researched for the treatment of schizophrenia. Fananserin was the first selective D4/5-HT2A antagonist to undergo clinical trials for schizophrenia. It has a high affinity for D4 (Ki 2.9 nM) and 5-HT2A (Ki 0.37 nM) receptors and is over 100-fold selective versus H1, a1 adrenergic, 5-HT1A and D2 dopamine receptors. Development of this compound was halted following phase II clinical trials due to lack of efficacy.

Licostinel (ACEA 1021) is a potent competitive antagonist at the glycine site on the N-methyl-D-aspartate (NMDA) receptor. The robust efficacy of glycine/NMDA antagonists, such as ACEA 1021, in animal model of brain ischemia, together with good safety profile in animal models and in clinical trials, suggested that this class of NMDA antagonists should have good chance of success in the clinic as neuroprotectants. The clinical trial of ACEA 1021 for stroke was discontinued, mainly due to low solubility and lack of metabolism of the drug that led to the observation of crystals in the urine of some of the patients. In vivo ACEA 1021 reduced the rate of propagation of cortical spreading depression, an effect consistent with blockade of NMDA receptors. ACEA 1021 also decreased audiogenic myoclonus in resuscitated rats following cardiac arrest, and the minimum alveolar concentration for halothane, effects which suggest a reduction of excitatory amino acid neurotransmission. ACEA 1021 crosses the blood-brain barrier and blocks the pathophysiologic consequences of NMDA receptor overstimulation. It was neuroprotective with a favorable therapeutic window in models of transient and permanent cerebral ischemia, epilepsy and pain.

Eniluracil (5-ethynyluracil, GW 776, 776C85) is a potent irreversible inhibitor of dihydropyrimidine dehydrogenase, the first enzyme in the catabolic pathway of 5-fluorouracil (5-FU), the most widely used drug in cancer chemotherapy. Eniluracil increases the oral bioavailability of 5-FU to 100%, facilitating uniform absorption and predictable toxicity. Eniluracil was being developed as a novel modulator of 5-FU for the treatment of cancer.

Piclamilast (RP 73401), is a selective PDE4 inhibitor. It is comparable to other PDE4 inhibitors for its anti-inflammatory effects. It has been investigated for its applications to the treatment of conditions such as asthma, dermatitis, rheumatoid arthritis. Emesis is the most commonly cited side effect of piclamilast.

Rosiglitazone acts as a highly selective and potent agonist at peroxisome proliferator activated receptors (PPAR) in target tissues for insulin action such as adipose tissue, skeletal muscle, and liver. It is FDA approved for the treatment of as an adjunct to diet and exercise to improve glycemic control in adults with type 2 diabetes mellitus. Inhibitors of CYP2C8 (e.g., gemfibrozil) may increase rosiglitazone levels; inducers of CYP2C8 (e.g., rifampin) may decrease rosiglitazone levels. Common adverse reactions include edema, weight gain, and headache.

Deracoxib (trade name Deramaxx, Novartis) is a non-steroidal anti-inflammatory drug of the coxib class, used in veterinary medicine for the control of postoperative pain and inflammation associated with orthopedic and dental surgery and for the control of pain and inflammation associated with osteoarthritis in dogs. Data indicate that deracoxib inhibits the production of PGE1 and 6-keto PGF1 by its inhibitory effects on prostaglandin biosynthesis. Deracoxib was shown to have antitumor effect against transitional cell carcinoma of the urinary bladder.

Trimegestone is a 19-norpregnane progestin. It has a potent progesterone receptor and very low androgen receptor affinities but no detectable affinity to oestrogen receptor. Trimegestone has been developed for use in conjunction with oestrogen and 17-beta-estradiol for postmenopausal hormone replacement therapy. In vitro studies have shown that trimegestone can inhibit cytochrome P450 2C19 (CYP2C19). Although its clinical importance is unknown, trimegestone can moderately elevate the plasma concentration of drugs metabolized through CYP2C19, such as citalopram, imipramine and diazepam. Trimegestone is an effective and well-tolerated new progestin, which does not negate the beneficial effects of oestrogen on lipids.

Satraplatin is a fourth-generation platinum-based anticancer drug developed by GPC Biotech, Inc. Unlike its predecessors cisplatin and carboplatin, which were administered intravenously, satraplatin was developed for oral administration. Satraplatin mediates its action through the formation of DNA adducts and inter- and intra-strand crosslinks. These adducts distort the DNA template with a deceleration of cells in S phase followed with G2 phase arrest. Satraplatin also inhibits DNA replication and transcription and induces signal transduction pathway, leading to cell cycle arrest and apoptosis. Satraplatin was investigated in phase III clinical trials against metastatic castrate-resistant prostate cancer. Despite the improvement in progression-free survival and palliation, overall survival was not improved with satraplatin therapy. The median survival was 61.3 weeks in the satraplatin group and 61.4 weeks in the prednisone and placebo group. In July 2007, GPC Biotech announced the withdrawal of the New Drug Application (NDA) for satraplatin, and the development of the drug was discontinued.

Pleconaril (Picovir) is an antiviral drug that was being developed by Schering-Plough for prevention of asthma exacerbations and common cold symptoms in patients exposed to picornavirus respiratory infections. Pleconaril binds to a hydrophobic pocket in viral protein 1, the major protein which comprises the capsid (the outer "shell") of picornaviruses. In enteroviruses, this prevents the virus from exposing its RNA, and in rhinoviruses, it also prevents the virus from attaching itself to the host cell. The results of two randomized, double-blind, placebo studies found Pleconaril treatment could benefit patients suffering from colds due to picornaviruses. Participants in the studies were healthy adults from Canada and the United States, with self-diagnosed colds that had occurred within 24 hours of trial enrollment. Participants were randomly given a placebo or two 200 mg tablets to take three times daily for five days. To increase absorption it was recommended to be taken after a meal. To monitor the effectiveness of Pleconaril, Participants recorded the severity of their symptoms and nasal mucosal samples were obtained at enrollment, day 3, day 6 and day 18. The two studies had a total of 2096 participates and more than 90% (1945) completed the trial. The most common reason for a participant not finishing the trial was an adverse event. Pleconaril treatment showed a reduction in nose blowing, sleep disturbance, and less cold medication used. The U.S. Food and Drug Administration rejected pleconaril in 2002 due to the side effects. The most commonly reported side effects were mild to a moderate headache, diarrhea, and nausea.