Safrazine (Safra) is a non-selective, irreversible monoamine oxidase inhibitor (MAOI) of the hydrazine class that was introduced as an antidepressant in the 1960s. Safrazine and electroconvulsive therapy were shown to be effective in the treatment of antidepressant-resistant depressions (ARD) but had the drawbacks of the high incidence of moderate or severe adverse reactions and high relapse rates, respectively. The use of safrazine was discontinued.

Teneligliptin is a DPP IV inhibitor which was developed by Mitsubishi Tanabe Pharma and now is used for the treatment of type 2 diabetes mellitus in Asia under the name Tenelia.

Mitoguazone is a guanylhydrazone derivative with potential antineoplastic activity. Mitoguazone inhibits S-adenosyl-L-methionine decarboxylase (SAMD), an enzyme involved in the synthesis of polyamines, resulting in a decreased proliferation of tumor cells, antimitochondrial effects, and p53-independent apoptosis. In the 1960s the drug was investigated in clinical trials. Despite the responses in acute leukemia, chronic myelogenous leukemia, lymphoma, multiple myeloma, head and neck cancer, esophageal cancer and other types of cancer, the development of the drug was discontinued because of marked myelosuppression and mucositis. Using a weekly schedule of administration, mitoguazone had minimal toxicity and showed limited activity in patients with lymphoma, esophageal cancer, prostate cancer, and other types of tumors.

Toloxatone is an antidepressant launched in 1984 in France for the treatment of depression. It is a selective reversible inhibitor of MAO-A (RIMA).

Melinamide is an antilipidemic agent similar to gemfibrozil. It acts to lower elevated serum lipids by reducing the very low-density lipoprotein fraction rich in triglycerides. Serum cholesterol may be decreased, particularly in those patients whose cholesterol elevation is due to the presence of IDL as a result of Type III hyperlipoproteinemia. Melinamide caused a decrease of the enhanced intestinal ACAT activity in diabetic rats, but did not affect intestinal cholesterol esterase activity. Marked improvement of hypercholesterolaemia in cholesterol-fed diabetic rats occurred concomitantly with the drug treatment. These results suggest that intestinal ACAT activity is closely related to the serum cholesterol level in diabetic rats, and show that melinamide lowers intestinal ACAT activity. Melinamide (Artes®) was the only marketed (in Japan) ACAT inhibitor. 04 Aug 2004 was withdrawn for Hypercholesterolaemia in Japan.

Udenafil is a new phosphodiesterase type 5 (PDE5) inhibitor used to treat erectile dysfunction. Udenafil inhibits the cyclic GMP specific phosphodiesterase type 5 (PDE5) which is responsible for degradation of Cyclic GMP in the corpus cavernosum located around the penis. Cyclic GMP causes smooth muscle relaxation and increased blood flow into the corpus cavernosum. So the inhibition of phosphodiesterase type 5 (PDE5) by Udenafil enhances erectile function by increasing the amount of Cyclic GMP. Udenafil has proven to have high efficacy and a favorable safety profile for a broad spectrum of erectile dysfunction patients, which are comparable to those of other PDE5Is. Due to the clinical properties of relatively rapid onset and long duration of action, Udenafil may be a better option for erectile dysfunction treatment according to patient-specific sex-life patterns. Udenafil is as effective in the treatment of diabetes mellitus-associated erectile dysfunction as other PDE5Is. Recent data suggest that the concomitant use of anti-hypertensive drugs does not significantly affect the efficacy and safety profile. Also, due to its clinical properties, Udenafil can be a daily-dosing option for the treatment of erectile dysfunction, as suggested by its favorable efficacy and safety profile. Udenafil has been approved in South Korea and will be marketed under the brand name Zydena.

Resminostat (4SC-201) is a hydroxamate HDAC inhibitor (a novel class I, IIb, and IV histone deacetylase inhibitor). Resminostat inhibits proliferation of a large variety of rodent and human cancer cell lines, likely via the Akt signalling pathway. Phase I and II clinical trials have evaluated the efficacy and safety of resminostat in the treatment of relapsed or refractory Hodgkin's Lymphoma, hepatocellular carcinoma, advanced colorectal carcinoma, and in patients with advanced stage mycosis fungoides or Sezary syndrome (an aggressive form of blood cancer). Results in patients with hepatocellular carcinoma showed that resminostat (combined with sorafenib) was safe, well-tolerated and displayed early signs of efficacy.

Topiroxostat was approved by Pharmaceuticals Medical Devices Agency of Japan (PMDA) on June 28, 2013. It was co-developed and marketed as Uriadec®/Topiloric® by Sanwa Kagaku Kenkyusho & Fuji Yakuhin. Topiroxostat is a xanthine oxidase inhibitor. Xanthine oxidase (XO) is a type of enzyme that generates reductive oxygen species, which catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthine to uric acid. Topiroxostat could reduce the production of uric acid in the body through the inhibition of xanthine oxidase. It is usually used for the treatment of gout and hyperuricemia.

Cetilistat (ATL-962) is a pancreatic lipase inhibitor, which was developed by Alizyme plc, in collaboration with Takeda Pharmaceutical Co Ltd for the potential treatment of obesity in patients with or without diabetes. This drug was approved for using in Japan

Exatecan (DX-8951f), a new hexacyclic camptothecin analogue, is a second-generation topoisomerase inhibitor that prevents rapidly dividing cells from replicating by interrupting DNA transcription, ultimately leading to cell death. Preclinical studies showed exatecan to have broad-spectrum antitumor efficacy. Exatecan is in phase III clinical trials for the treatment of pancreas cancer. However, there is no recent report of this research. The compound was co-developed by Daiichi Pharmaceutical (now Daiichi Sankyo) and Yakult Honsha.