Aplaviroc (GW873140) is a small-molecule noncompetitive allosteric CCR5 antagonist or HIV entry inhibitor (EI) that binds specifically to human CCR5 and exhibits potent anti-HIV activity in vitro in the nanomolar or subnanomolar range. Aplaviroc has exhibited potent in vivo antiviral activity (1.66 log decrease in viral load at nadir) following 10 days of monotherapy. In vitro studies of antiviral activity demonstrate that aplaviroc is active against HIV isolates from a variety of clades as well as those resistant to current HIV therapies targeting RT, PR, and gp41. However, GlaxoSmithKline has decided to terminate Phase III trials of aplaviroc after encountering additional cases of liver damage in patients taking the drug.

ISOMYLAMINE is a spasmolytic and smooth muscle relaxant.

Etalocib (LY-293111 or VML 295) is a potent and orally active leukotriene B4 receptor antagonist of the biphenylphenol class. It efficiently blocks neutrophil activation and subsequent inflammation. Additionally, it exerts antineoplastic properties through induction of cell cycle arrest and apoptosis in tumor cells. Etalocib was being developed for the treatment of inflammatory diseases and solid tumors.

Varespladib (LY315920; A-001) is a potent and selective inhibitor of IIa, V, and X isoforms of human non-pancreatic secretory phospholipase A2 with nM IC50. The molecule acts as an anti-inflammatory agent by disrupting the first step of the arachidonic acid pathway of inflammation. Varespladib methyl is being developed by Anthera Pharmaceuticals Inc for the potential treatment of coronary artery disease, acute coronary syndrome and inflammation. Varespladib methyl is a prodrug that is rapidly metabolized to varespladib, and both compounds are able to potently inhibit the enzymes of the human secretory phospholipase groups. Phase II clinical trials of varespladib methyl in patients with coronary artery disease, rheumatoid arthritis, asthma and ulcerative colitis revealed that the drug was well tolerated. Varespladib methyl did not demonstrate a good efficacy profile in patients with rheumatoid arthritis, asthma and ulcerative colitis; whereas in patients with coronary artery disease, varespladib methyl consistently reduced LDL-cholesterol levels, (elevated LDL-cholesterol levels are a marker of increased cardiovascular risk). Varespladib methyl could represent a novel therapy for the treatment of cardiovascular disease, although the efficacy, safety profile and advantages of this drug compared with existing therapeutic options would need to be established in upcoming phase III trials.

Brequinar is a synthetic quinolinecarboxylic acid analogue with antineoplastic properties. Brequinar inhibits the enzyme dihydroorotate dehydrogenase, thereby blocking de novo pyrimidine biosynthesis. This agent may also enhance the in vivo antitumor effect of antineoplastic agents such as 5-FU. Brequinar had been in phase II clinical trials by Bristol-Myers Squibb for the treatment of cancer and transplant rejection. However, this research has been discontinued. Brequinar had been also in preclinical studys for the treatment of cytomegalovirus infections. However, this research has been discontinued.

Tixanox is an antiallergic drug. It blocks histamine release from human lung induced by anti-IgE. Tixanox has been shown to be orally active against exercise-induced asthma in man.

Tresperimus is a new stable immunosuppressive analog of 15-deoxyspergualin (DSG) obtained by organic chemical synthesis. It was initially developed as an antitumor agent. Tresperimus has been designed to be chemically stable in aqueous solution. Tresperimus controlled alloreactivity in a fully major histocompatibility complex (MHC) mismatched rat cardiac transplant model and also induced donor-specific long-lasting unresponsiveness. Posttransplant tresperimus therapy effectively protected mice from lethal graft-versus-host disease (GVHD) in a dose-related manner. It has been shown to suppress graft rejection as efficiently as cyclosporine A. Indeed, a short course of tresperimus has similar or better effects compared to the effects of cyclosporine in bone marrow, cardiac, and skin transplant models. Prevention of rejection is related to the induction of donor-specific tolerance without affecting immunity to third-party antigens. In addition, CD4+ T-cells from tresperimus-treated animals can transfer donorspecific tolerance to naive animals, an effect not seen with cyclosporine or other traditional immunosuppressive drugs. The mechanism by which tolerance is induced is not clear. Tresperimus binds to Hsc70, a heat shock protein– chaperoned peptide that, among other effects, inhibits nuclear localization of nuclear factor (NF)-kB, which is required for CD40 and CD28 ligation signaling in antigen-presenting cells, an important early step in T-cell costimulation. Locally administered tresperimus appears to be a potential immunosuppressive agent in the management of intraocular inflammation. Tresperimus had been in phase III clinical trial for the treatment of graft-versus-host disease. However, this development was discontinued.

Metesind (AG-331) is a lipophilic thymidylate synthase inhibitor. It inhibits the cofactor binding site of the enzyme. It exerts cytotoxic properties. Metesind was being developed as an anticancer and antimetabolite agent.

Gemcabene calcium (PD 72953), the monocalcium salt of a dialkyl ether dicarboxylic acid, is a lipid-regulating compound that was first described in 1998. It down-regulates apolipoprotein C-III expression, enhancing the clearance of very low density lipoprotein (LDL), and reduces plasma triglycerides. It also raises high-density lipoprotein cholesterol (HDL). Unlike fibrates (blood trygliceride level lowering drugs), its mechanism of action is not linked to agonist or antagonist activity on PPAR-α receptors. There is limited information on the exact mechanism of action, but an anti-inflammatory profile was found, associated with a lowered expression of the high-sensitivity C-reactive protein gene regulating mechanisms. Gemcabene (administered as 6, 6’-oxybis [2, 2-dimethyl-4-hexanoic acid] monocalcium salt) has been investigated for treatment in a wide range of hyperlipidaemias, as well as atherosclerosis, and cardiovascular disorders. Gemcabene is generally well tolerated. One phase 2 study testing the preliminary efficacy and safety of gemcabene in children with established nonalcoholic fatty liver disease has been stopped early due to increasing weight and a rise in liver fat content in patients. Clinical trials are still ongoing.

Dexniguldipine (B8509-035, (-)-(R)-niguldipine) is a new dihydropyridine derivative, that exerts selective antiproliferative activity in a variety of tumor models and, in addition, has a high potency in overcoming multidrug resistance. Dexniguldipine is ( - )-(R)-enantiomer of niguldipine, of which the ( )-(S)-enantiomer shows pronounced cardiovascular hypotensive activity due to its high affinity for the voltage-dependent Ca2 channel. As compared with the (S)-enantiomer, the (R)-enantiomer has a 40-fold lower affinity for the Ca 2 channel and, accordingly, only minimal hypotensive activity in animal pharmacology models. Dexniguldipine have shown antiproliferative activity in several tumor cell lines, but the concentrations necessary to inhibit growth have varied by several orders of magnitude between cell lines. Initial results of preclinical investigations for the evaluation of the mechanism of its antiproliferative activity demonstrate that dexniguldipine interferes with intracellular signal transduction by affecting phosphoinositol pathways, protein kinase C expression, and intracellular Ca 2 metabolism. In a series of human tumor xenografts in vitro, dexniguldipine demonstrated selective antiproliferative activity against several tumor types, e.g., melanoma and renal-cell carcinoma. Striking results were obtained in a hamster model, in which neuroendocrine lung tumors could be completely eradicated by 20 weeks of oral treatment with 32.5mg/kg dexniguldipine, whereas Clara-cell-type lung tumors were not affected. In in vitro studies, dexniguldipine has been found to bind to P-glycoprotein (P-gp) and to enhance the cytotoxicity of chemotherapeutic agents such as doxorubicin and etoposide in several cell lines The synergistic effect may well be associated with the reversal of multidrug resistance (MDR) related to the activity of P-gp. In the clinical therapy of cancer, resistance to many cytostatic drugs is a major cause of treatment failure. However, the high potency of dexniguldipine (about 10-fold as compared with that of verapamil in vitro) and its low cardiovascular activity provide the opportunity to achieve blood or tumor concentrations that might be high enough to overcome Mdr 1 resistance in patients without producing dose-limiting cardiovascular effects.