Inhaled pan-selectin antagonist Bimosiamose attenuates airway inflammation in COPD.

Selectins, a family of cell adhesion molecules, are involved in leukocyte extravasation to sites of inflammation. We investigated the safety and efficacy of the inhaled pan-selectin antagonist Bimosiamose in patients with chronic obstructive pulmonary disease (COPD). 77 COPD patients (mean forced expiratory volume in 1 s, 57% pred.) were enrolled in a cross-over, double-blind, randomized, Placebo-controlled, multi-center trial. Bimosiamose (10 mg) or Placebo was inhaled twice daily via the breath actuated nebulizer Akita2 Apixneb™ for 28 days on top of standard bronchodilator therapy. Efficacy was assessed by measurement of inflammatory parameters in induced sputum (differential cell count, interleukin-8, matrix-metalloproteinase-9, myeloperoxidase) and lung function at day 28 of both treatment periods. The total adverse event ratio of Bimosiamose compared to Placebo treatment was balanced. Compared to Placebo, treatment with Bimosiamose led to a decrease of the interleukin-8 concentration (-9.49 ng/mL, 95%CI -18.8 to -2.7 ng/mL, p = 0.008), for the neutrophil count a difference of -0.368 × 10(6) cells/mL (95%CI -1.256 to 0.407 × 10(6)/mL, p = 0.313) was found. The macrophage count decreased by -0.200 × 10(6) cells/mL (95%CI -0.365 to -0.044 × 10(6) cells/mL, p = 0.012). Most lung function parameters showed a small numeric increase. Inhalation of Bimosiamose for 28 days was safe and well tolerated in patients with COPD. It led to an attenuation of airway inflammation (EudraCT 2009-017257-35; NCT ID: NCT01108913).

The pharmacokinetics of subcutaneously injected Bimosiamose disodium in healthy male volunteers.

Bimosiamose is a novel synthetic pan-selectin antagonist developed for the treatment of acute and chronic inflammatory disorders. Therefore the pharmacokinetics of Bimosiamose disodium were studied in healthy male volunteers after single and multiple subcutaneous injections. A randomized, double-blind, placebo-controlled dose escalation trial was carried out. The subjects received subcutaneous injections of placebo or 100, 200 or 300 mg Bimosiamose disodium into the abdomen. Plasma and urine concentrations of Bimosiamose were determined. The maximum plasma concentration was 2.17+/-0.70 microg/ml and the AUC(0-infinity) 11.1+/-2.9 h microg/ml after the highest dose on day 1 (mean+/-SD). For the apparent clearance CL/f 28.7+/-7.3 l/h and the terminal half life t(1/2) 3.7+/-0.6 h were calculated. The mean residence time MRT(infinity) of 5.5 to 6.3 h for s.c. injection exceeded that after i.v. infusion due to an extended absorption time. For multiple dosing, constant pre-dose concentrations of about 20 ng/ml may be reached after two subsequent doses of 200 or 300 mg Bimosiamose disodium once daily. Almost 15% of the administered drug was excreted unchanged in urine. Moreover, Bimosiamose was well tolerated.

PDZ Domain-mediated interaction of interleukin-16 precursor proteins with myosin phosphatase targeting subunits.

The cytokine interleukin-16 is generated by posttranscriptional cleavage by caspase-3 of two large precursor isoforms. The smaller protein of 67 kDa (pro-IL-16) is expressed in cells of the immune system and contains three PDZ (postsynaptic density/disc large/zona occludens-1) domains, whereas the larger 141-kDa neuronal variant (npro-IL-16) has two additional PDZ domains in its N-terminal extension that interact with neuronal ion channels. Using the yeast two-hybrid approach we have identified three closely related myosin phosphatase targeting subunits, MYPT1, MYPT2, and MBS85, as binding partners of the IL-16 precursor proteins. These interactions were verified using pull-down assays, coimmunoprecipitations, and plasmon resonance experiments. Binding requires the intact PDZ2 domain of pro-IL-16 and highly related C-terminal regions in the ligands consisting of a short leucine zipper and an indispensable serine at the -1 position, suggesting a novel unconventional PDZ binding mode. Pro-IL-16 and the myosin phosphatase targeting subunits colocalize along actomyosin filaments and stress fibers in transfected COS-7 cells. By modulating and targeting the catalytic phosphatase subunit to its substrates, MYPT1, MYPT2, and MBS85 regulate various contractile processes in muscle and non-muscle cells. Our findings indicate an involvement of the IL-16 precursor molecules in myosin-based contractile processes, most likely in cell motility, providing a functional link to the chemotactic activity of the mature cytokine. Alternatively, an intracellular complex of npro-IL-16, ion channels, and components of myosin motors in neurons suggests a role in protein targeting.