Taurolidine [bis(1,1-dioxoperhydro-1,2,4-thiadiazinyl-4)-methane (TRD)], a product derived from the aminosulfoacid taurin, was first described as an anti-bacterial substance. Taurolidine is a small dimeric molecule with molecular weight 284. It comprises the semiconditional amino acid taurine. Taurolidine was originally designed as a broad-spectrum antibiotic. Taurolidine has a broad antimicrobial spectrum of activity that is effective against aerobes and anaerobes, Gram-negative and Gram-posi-tive bacteria as well as yeasts and moulds in vitro. Taurolidine is also effective against methicillin-resistant and vancomycin-resistant bacteria (MRSA, VISA and VRE). It was mainly used in the treatment of patients with peritonis as well as antiendoxic agent in patients with systematic inflammatory response syndrome. It has been shown to be an effective bactericidal agent against both aerobic and anaerobic bacteria. It is currently licensed for intraperitoneal use in several European countries for the treatment of peritonitis. The compound appears to be nontoxic and has an excellent safety record since its initial introduction over 30 years ago. Taurolidine also possesses antiadherence properties and has been shown in vivo to reduce the extent and severity of postoperative peritoneal adhesions. It also possesses a strong anti-inflammatory action. This action appears, at least in part, to arise through its ability to inactivate endotoxin. Inflammation-induced tumor development is well described in the literature. Taurolidine’s anti-inflammatory and antiadherence properties prompted an investigation to examine whether it has a role in antitumor therapy. Taurolidine induces cancer cell death through a variety of mechanisms. It appears to act through enhancing apoptosis, inhibiting angiogenesis and tumor adherence, downregulating proinflammatory cytokine and endotoxin levels, and stimulating the immune system in response to surgically induced trauma. Taurolidine is currently in preclinical development for neuroblastoma. In February 23, 2018 the U.S. Food and Drug Administration (FDA) granted orphan drug designation to taurolidine for the treatment of neuroblastoma. Taurolidine is a key component in the Neutrolin®, a novel anti-infective solution for the reduction and prevention of catheter-related infections and thrombosis in patients requiring central venous cathers in end stage renal disease. Neutrolin contains a mix of Taurolidine, Citrate and Heparin. Neutrolin is designed to: 1) Aid in the prevention of Catheter-Related Bloodstream Infections (CRBIs) and 2) Prevent catheter dysfunction (due to blood clotting).

Gepirone (brand name Travivo) is an investigational azapirone antidepressant and anxiolytic drug in development for the treatment of major depressive disorder but has yet to be marketed. Like other azapirones, it acts as a selective partial agonist of the 5-HT1A receptor. Gepirone has been under development in the U.S. in an extended release form (referred to as Gepirone ER). It has been rejected multiple times by the FDA during the drug approval process and Phase III studies evaluating its use in the treatment of MDD were prematurely terminated. These were the initial Phase III studies of gepirone ER in MDD, and the effective dose range had not been determined. In March 2016, the FDA reversed its decision and gave gepirone ER a positive review, clearing the way for the drug to finally gain market approval in the U.S. In addition to its antidepressant and anxiolytic properties, gepirone has been found to improve symptoms of sexual dysfunction in men and women, similarly to the marketed 5-HT1A receptor agonist flibanserin. The pro-sexual effects appear to be independent of its antidepressant and anxiolytic effects. Mechanism of action studies have demonstrated that gepirone possesses a much greater selectivity for 5-HT1A receptors over dopamine D2 receptors. Long-term studies have shown that gepirone has a differential action at presynaptic (agonist) and post-synaptic (partial agonist) 5-HT1A receptors. Treatment with gepirone ER desensitizes presynaptic 5-HT1A receptors, which decreases serotonin autoregulatory inhibition and enhances activation of postsynaptic 5-HT1A receptors. As a partial agonist gepirone ER acts as an agonist when endogenous serotonin is not present and as an antagonist when endogenous serotonin is present. Overall, gepirone ER increases serotonin production when insufficient amounts are present, and decreases serotonin production when excess amounts are present. Gepirone has been tested in Phase II clinical trial as antidepressant medication for pharmacotherapy for cocaine dependent subjects.

Maribavir (previously known as 1263W94) is a novel benzimidazole riboside compound. This drug was in phase III of clinical trial for the prevention of cytomegalovirus (CMV) infections in transplant patients, sponsored by ViroPharma. However, drug failed to demonstrate a higher efficacy rate than the placebo. Maribavir has activity against cytomegalovirus and Epstein-Barr virus (EBV), but not against other human herpesviruses. Maribavir’s mechanism of action is unique and is complex compared to the currently approved antivirals for CMV. Maribavir inhibits the viral UL97 kinase rather than the viral DNA polymerase. The UL97 kinase is important for viral DNA elongation, DNA packaging, and nuclear egress of encapsidated viral DNA. In addition, maribavir inhibits the EBV DNA polymerase processivity factor (BMRF1), reduces the level of certain EBV glycoproteins, and inhibits viral transcription. However, future work will be designed to address the interaction of MBV and BGLF4 and to evaluate the mechanisms through which maribavir downregulates viral transcripts. BGLF4 belongs to the family of conserved herpesvirus PKs, which includes HCMV UL97, HSV UL13, and HSV US3. Maribavir does need to be phosphorylated for its activity.

Tivozanib (formerly AV-951, KRN-951) is a potent and selective VEGFR tyrosine kinase inhibitor and inhibits angiogenesis and vascular permeability in tumor tissues. It completed phase III a trial investigation for the treatment of renal cell carcinomas, but has not been still approved. In addition, this drug is in the phase II of clinical trial for the investigation it in patients with glioblastoma and colorectal carcinoma.

Fexinidazole is an antiparasitic drug, which is in the phase III of clinical trial for the treatment of Human African Trypanosomiasis, and in the phase II for the treatment Disease, Chagas and Visceral Leishmaniosis. However, for the Visceral Leishmaniosis, studies were terminated, due to lack of efficacy. Fexinidazole rapidly metabolized to two active metabolites, a sulfone and a sulfoxide, which prolong the pharmacological action of parent drug. These metabolites retaine trypanocidal activity but are less effective in nifurtimox-resistant lines, which can lead to the potential danger in the use of fexinidazole as a monotherapy.

Viloxazine is an antidepressant drug was used to treat patients with depression. Viloxazine inhibits noradrenaline uptake. This drug was approved in some Europe countries, but not in the USA, but then it was discontinued because of competition from other drugs. In the frame of drug repositioning, Viloxazine participated in clinical trials for the treatment of attention deficit hyperactivity disorder. Phase II of trials was successfully passed.

Voclosporin (trans-ISA247) is a Cyclosporin A derivative and immunosuppressive compound currently being investigated for the treatment of psoriasis, lupus nephritis and for the prevention of organ rejection in kidney transplant patients. An animal study showed that a lower blood level of Voclosporin was able to produce a greater or similar inhibition of lymphocyte proliferation, expression of T-cell activation surface antigens, and T-cell cytokine production compared to Cyclosporin A. Voclosporin has been shown to be an efficacious and safe immunosuppressant in phase IIb and phase III trials in renal transplant recipients and in plaque psoriasis patients. In clinical trials, Voclosporin added to standard-of-care induction therapy for lupus nephritis increases complete renal remission (CRR) rates, but higher rates of adverse events including death were observed.

Amisulpride, a benzamide derivative, shows a unique therapeutic profile being atypical antipsychotic. At low doses, it enhances dopaminergic neurotransmission by preferentially blocking presynaptic dopamine D2/D3 autoreceptors. At higher doses, amisupride antagonises postsynaptic dopamine D2 and D3 receptors, preferentially in the limbic system rather than the striatum, thereby reducing dopaminergic transmission. In addition its antagonism at serotonin 5-HT7 receptors likely underlies the antidepressant actions. Amisulpride is approved for clinical use in treating schizophrenia in a number of European countries and also for treating dysthymia, a mild form of depression, in Italy.

Fluoroestradiol F-18 is a derivative of estradiol. where hydrogen at position 16 is replaced by radioactive fluorine. Fluoroestradiol F-18 is taken up by tumor cells, expression estrogen receptor, and it is clinically evaluated for PET imaging to detect and stage breast cancer, ovarian cancer, and cancer of uterine endometrium and myometrium.

Nifurtimox is a nitrofuran derivative used as a primary agent in the treatment of American trypanosomiasis (Chagas' disease) caused by Trypanosoma cruzi, especially in the acute, early stage of the disease. The efficacy of nifurtimox in the treatment of chronic Chagas' disease varies from one country to another, possibly due to variation in the sensitivity of different strains of the organism. Nifurtimox has also been used to treat African trypanosomiasis (sleeping sickness) and is active in the second stage of the disease (central nervous system involvement). When nifurtimox is given on its own, about half of all patients will relapse, but the combination of melarsoprol with nifurtimox appears to be efficacious. Nifurtimox forms a nitro-anion radical metabolite that reacts with nucleic acids of the parasite causing significant break down of DNA. Nifurtimox undergoes reduction and creates oxygen radicals such as superoxide. These radicals are toxic to T. cruzi. Mammalian cells are protected by the presence of catalase, glutathione, peroxidases, and superoxide dismutase. Accumulation of hydrogen peroxide to cytotoxic levels results in parasite death. Side effects occur following chronic administration, particularly in elderly people. Major toxicities include immediate hypersensitivities such as anaphylaxis and delayed hypersensitivity reaction involving icterus and dermatitis. Central nervous system disturbances and peripheral neuropathy may also occur.