Omtriptolide (previously known as PG490-88 or F60008), an immunosuppressant that has been shown to be the safe and potent antitumor agent and it has been approved entry into Phase I clinical trial for the treatment of prostate cancer in the USA. In addition, the drug is participating in phase I clinical trial for the treatment of myeloid leukemia. Experiments on animals have shown omtriptolide was highly effective in the prevention of murine graft-versus-host disease (GVHD). The immunosuppressive effect of the drug was mediated by inhibition of alloreactive T cell expansion through interleukin-2 production. However, this study was discontinued. Recently published article has shown omtriptolide possesses the potential as a prophylactic agent to prevent ischemia/reperfusion (I/R)-induced lung injury.

Omtriptolide (previously known as PG490-88 or F60008), an immunosuppressant that has been shown to be the safe and potent antitumor agent and it has been approved entry into Phase I clinical trial for the treatment of prostate cancer in the USA. In addition, the drug is participating in phase I clinical trial for the treatment of myeloid leukemia. Experiments on animals have shown omtriptolide was highly effective in the prevention of murine graft-versus-host disease (GVHD). The immunosuppressive effect of the drug was mediated by inhibition of alloreactive T cell expansion through interleukin-2 production. However, this study was discontinued. Recently published article has shown omtriptolide possesses the potential as a prophylactic agent to prevent ischemia/reperfusion (I/R)-induced lung injury.

Gisadenafil is a phosphodiesterase V inhibitor in clinical development at Pfizer. It had been in phase II clinical trials for the treatment of Benign prostatic hyperplasia; Chronic obstructive pulmonary disease; Erectile dysfunction; Overactive bladder. Treatment-emergent adverse events were: headache, myalgia, dyspepsia, back pain.

Nemorubicin, a doxorubicin derivative, is a DNA-intercalator, topoisomerase and RNA synthesis inhibitor that was undergoing development with Nerviano Medical Sciences (Nerviano MS; formerly Pharmacia Italia) for the treatment of solid tumours, specifically, the loco-regional treatment of primary liver tumours (hepatocellular carcinoma). The drug is active on tumors resistant to alkylating agents, topoisomerase II inhibitors and platinum derivatives. It works primarily through topoisomerase I inhibition. Of note, Nemorubicin is active in cells with upregulation of the nucleotide excision repair (NER) pathway, where current therapies fail. Nemorubicin is biotransformed in the liver into cytotoxic metabolites that may further contribute to render this drug highly active against primary liver tumors or liver metastases. Clinical trials were conducted in Europe, US and China with Nemorubicin given at different dose-schedules and by different routes of administration: as single agent by systemic IV route, oral route and by intra-hepatic artery (IHA) infusion alone or in combination with cisplatin.

Proadifen is an inhibitor of drug metabolism and cytochrome P450 enzyme system activity. It stimulated the release of prostacyclin (PGI2) from the rabbit aorta, bovine aorta and human umbilical vein in vitro, but had no effect on cultured smooth muscle from the bovine aortic media. In human platelets, proadifen inhibited prostaglandin and thromboxane production induced by A23187, thrombin, and ADP. Proadifen might thus constitute the prototype of a new class of antiplatelet drugs.

trans-Ketoconazole was identified as impurity of an antifungal compound cis-ketoconazole. Cis-Ketoconazole displayed broad-spectrum in vivo activity in a wide range of experimental fungal infections caused by different fungi in a variety of animal models. trans-isomer of ketoconazole is less active than cis-ketoconazole.

Paritaprevir is a potent inhibitor of the NS3/4A protease that rapidly and consistently suppresses HCV. Paritaprevir is metabolized by the Cytochrome P450 isoform 3A (CYP3A); therefore, ritonavir was used concurrently to increase plasma concentrations and to prolong the half-life of this agent allowing for once-daily dosing. Several antiviral regimens combining paritaprevir with other agents have shown impressive results, tolerable side effects, and importantly, provided support of ‘all-oral’ interferon-free regimens against HCV. Paritaprevir monotherapy is discontinued now but paritaprevir is used as a component of Viekira Pak and Technivie for the treatment of patients with genotype 1 chronic hepatitis C virus (HCV) infection.

Cisapride is chemically related to metoclopramide, but unlike metoclopramide, it does not cross the blood-brain barrier or have antidopaminergic effects. Cisapride is a serotonin-4 (5-HT4) receptor agonist. Cisapride was indicated for the symptomatic treatment of adult patients with nocturnal heartburn due to gastroesophageal reflux disease. The Food and Drug Administration (FDA) in America stopped the marketing of cisapride as of 14th July 2000. They had received at least 341 reports of heart rhythm abnormalities and these led to 80 deaths. Other reported adverse effects are: headache, diarrhea, abdominal pain, nausea, constipation. Cisapride for animals has been found helpful in some cases of megaesophagus and is a common treatment for feline megacolon. Clarithromycin, erythromycin, and troleandomycin markedly inhibit the metabolism of cisapride. Concurrent administration of certain anticholinergic compounds, such as belladonna alkaloids and dicyclomine, would be expected to compromise the beneficial effects of cisapride.