ISATORIBINE, a guanosine analog, is an immunopotentiating agent. It is a selective agonist of toll‐like receptor 7, a pattern-recognition receptor that activates the innate immune response.

Eritoran (E-5564) is a synthetic lipid A analog that has been designed to antagonize the effects of lipopolysaccharide (LPS) and has been found to do this by interacting with Toll-like receptor 4, the cell surface receptor for LPS. Preclinical in vitro and in vivo studies of eritoran tetrasodium indicate it can limit excessive inflammatory mediator release associated with LPS and improve survival in sepsis models. Clinically, eritoran was being investigated for the treatment of severe sepsis, septic shock, and other endotoxin-mediated indications. Eritoran development has been discontinued.

CC-220 is a potent cereblon modulating agent that displays anti-proliferative, pro-apoptotic and immunomodulatory activity on sensitive and resistant multiple myeloma cell lines. CC-220 is currently under clinical investigation for systemic lupus erythematosus and multiple myeloma as a single agent, or in combination with dexamethasone in patients who may have previously been exposed to pomalidomide. Comparable to other Cereblon-binding agents, ex vivo treatment of CC-220 on B-cells, T-cells, and monocytes leads to the degradation of the hematopoietic transcription factors Ikaros (IKZF1) and Aiolos (IKZF3). followed by disruption of the multiple myeloma promoting c-Myc/IRF4 axis.

Vapitadine (R129160; Hivenyl™) is an antihistamine that Barrier Therapeutics is developing as a treatment for allergic reactions of the skin, such as those associated with hives and for the itch associated with atopic dermatitis. Vapitadine is a new selective, non-sedative H1antihistamine. In several in vitro and in vivo pharmacological models, vapitadine is at least as potent as cetirizine (Zyrtec®) and does not penetrate the blood-brain barrier. An advantage of vapitadine over other antihistamines may be the absence of the sedation, even at high doses. Vapitadine had been in phase II clinical trials for the treatment of patients with atopic dermatitis. However, no development has been reported.

Prospidium is a diazoniadispiro(5.2.5.2)hexadecane derivative patented by All-Union Scientific-Research Chemical-Pharmaceutical Institute as an antitumor agent that does not inhibit hematopoiesis. In preclinical models, The injection of Prospidium to thyroidectomized and hypophysectomized rats inhibited tumor growth to a greater extent than in intact rats. Larynx and lung cancer, lymphogranulomatosis, leucosis, etc. can be successfully treated with Prospidium at doses of 60-120 mg daily.

Sulfonterol is a benzenemethanol derivative patented by Smith Kline and French Laboratories as a bronchodilator. Sulfonterol acts as a β-adrenergic partial agonist.

Atiprimod is an oral azaspirane which was initially developed by Smith Kline and French Laboratories for treating rheumatoid arthritis (discontinued in phase I). Due to its anti-inflammatory, antineoplastic, and antiangiogenic properties, the drug was tested in patients with Neuroendocrine Carcinoma and Multiple Myeloma and reached phase II (discontinued). In vitro studies revealed that atiprimod exerts its action by inhibiting the phosphorylation of signal transducer and activator of transcription 3 (STAT3), blocking the signalling pathways of interleukin-6 and vascular endothelial growth factor (VEGF) and downregulating the anti-apoptotic proteins Bcl-2, Bcl-XL, and Mcl-1, thereby inhibiting cell proliferation, inducing cell cycle arrest, and inducing apoptosis.

Moxilubant is an orally active leukotriene B4 antagonist patented by Ciba-Geigy A.-G. and studied for psoriasis, rheumatoid arthritis, and chronic obstructive pulmonary disease treatment. Moxilubant inhibits LTB4 signaling with a potency of 2–4 nM. In a phase 1 study in 10 healthy volunteers, Moxilubant was administered orally once or twice daily for 7 days at doses ranging from 100 to 500 mg. At dose levels of 150 mg and above, LTB4 pathway inhibition reached at least 75%. At doses of 300 mg and above, pathway inhibition reached 100%. A Phase 2 study was conducted in 24 patients with COPD treated with 240 mg/day Moxilubant for 4 weeks. In this study, there were no changes in sputum cell counts or biomarkers or in spirometry measures, even though plasma levels of Moxilubant were sufficient to significantly reduce pathway signaling.

Efletirizine is histamine H1 receptor antagonist. Restricted to topical use. It was under investigation in Phase III (in Europe) clinical studies for the treatment of allergic rhinitis and chronic idiopathic urticarial. Research was discontinued in 2005 due to limited clinical efficacy and safety data. Efletirizine also reduced ocular itching.

Vicriviroc or SCH 417690 is a potent and selective antagonist of the CCR5 receptor. vicriviroc binds specifically to the CCR5 receptor and prevents infection of target cells by CCR5-tropic HIV-1 isolates. In antiviral assays, vicriviroc showed potent, broad-spectrum activity against genetically diverse and drug-resistant HIV-1 isolates and was consistently more active than SCH-C in inhibiting viral replication. This compound demonstrated synergistic anti-HIV activity in combination with drugs from all other classes of approved antiretrovirals. Competition binding assays revealed that vicriviroc binds with higher affinity to CCR5 than SCH-C. Functional assays, including inhibition of calcium flux, guanosine 5'-[35S]triphosphate exchange, and chemotaxis, confirmed that vicriviroc acts as a receptor antagonist by inhibiting signaling of CCR5 by chemokines. Finally, vicriviroc demonstrated diminished affinity for the human ether a-go-go related gene transcript ion channel compared to SCH-C, suggesting a reduced potential for cardiac effects. Vicriviroc represented a promising new candidate for the treatment of HIV-1 infection. Vicriviroc for HIV treatment was previously in Phase III studies but has since been discontinued.