Alamifovir is a novel antiviral agent which was under development with Mitsubishi Pharma Corporation in Japan as a potential treatment for hepatitis B (HBV). Alamifovir and its hydrolyzed derivatives have shown preclinical efficacy activity against wild-type and lamivudine-resistant hepatitis B virus. The effective concentration of alamifovir required to reduce replication by 50% (EC50) for the wild-type was 0.027 uM, which is approximately 20 times less than lamivudine, and the EC50 for the lamivudine-resistant mutants was 2.6 to 3.3 uM. The mechanism of action of alamifovir appears to be via the inhibition of the protein priming reaction and the packaging reaction, thereby decreasing HBV replication. Alamifovir`s development has been discontinued.

Teniloxazine (also known as sulfoxazine or sufoxazine or Y 8894) was developed as an antidepressant. Teniloxazine belongs to the selective norepinephrine reuptake inhibitors (NRIs) and was studied for the treatment of the major depressive disorder. Clinical trials have shown that 50 mg of the drug lacked the anticholinergic, sedative and cardiovascular effects. In the elderly, some effects were recognized, in part, due to pharmacokinetic alteration. In addition, teniloxazine was studied for patients with Alzheimer's disease, however, doesn’t exist any development report for this study.

Osemozotan (also known as MKC-242) was developed as a selective 5-HT1A receptor agonist. Experiments on animal have shown that osemozotan improved most abnormal behaviors such as isolation rearing. Osemozotan was being investigated for the treatment of pain, aggressive behavior, anxiety, depression, obsessive-compulsive disorder, and drug dependence with methamphetamine and cocaine. However, all these studies were suspended. In the USA osemozotan participated in phase II clinical trial for the insomnia patients, however, the study was terminated because of the license agreement.

Traxanox is a diuretic agent possessing an uricosuric effect in animals. The diuretic and uricosuric effects of the drug have also been demonstrated in normotensive healthy subjects. The chronic administration of traxanox reduces serum uric acid level as well as blood pressure in patients with mild to moderate hypertension. This reduction in serum uric acid is due in part to a traxanox-induced elevation of urinary uric acid excretion. Traxanox sodium stimulates the phagocytic activity of leukocytes or macrophages and prevents the drug-induced suppression of the phagocytic activity of these cells. Traxanox may be clinically effective in treating patients with nasal allergies. The mode of action of traxanox on inflammatory responses resembles that of D-penicillamine or levamisole, so that it may prove to be clinically effective in treating rheumatoid arthritis. Also, traxanox may be effective for the treatment of allergic bronchial asthma.

Teniloxazine (also known as sulfoxazine or sufoxazine or Y 8894) was developed as an antidepressant. Teniloxazine belongs to the selective norepinephrine reuptake inhibitors (NRIs) and was studied for the treatment of the major depressive disorder. Clinical trials have shown that 50 mg of the drug lacked the anticholinergic, sedative and cardiovascular effects. In the elderly, some effects were recognized, in part, due to pharmacokinetic alteration. In addition, teniloxazine was studied for patients with Alzheimer's disease, however, doesn’t exist any development report for this study.

Traxanox is a diuretic agent possessing an uricosuric effect in animals. The diuretic and uricosuric effects of the drug have also been demonstrated in normotensive healthy subjects. The chronic administration of traxanox reduces serum uric acid level as well as blood pressure in patients with mild to moderate hypertension. This reduction in serum uric acid is due in part to a traxanox-induced elevation of urinary uric acid excretion. Traxanox sodium stimulates the phagocytic activity of leukocytes or macrophages and prevents the drug-induced suppression of the phagocytic activity of these cells. Traxanox may be clinically effective in treating patients with nasal allergies. The mode of action of traxanox on inflammatory responses resembles that of D-penicillamine or levamisole, so that it may prove to be clinically effective in treating rheumatoid arthritis. Also, traxanox may be effective for the treatment of allergic bronchial asthma.

Osemozotan (also known as MKC-242) was developed as a selective 5-HT1A receptor agonist. Experiments on animal have shown that osemozotan improved most abnormal behaviors such as isolation rearing. Osemozotan was being investigated for the treatment of pain, aggressive behavior, anxiety, depression, obsessive-compulsive disorder, and drug dependence with methamphetamine and cocaine. However, all these studies were suspended. In the USA osemozotan participated in phase II clinical trial for the insomnia patients, however, the study was terminated because of the license agreement.