SOUTH SAN FRANCISCO, Calif., Feb. 26, 2013 /PRNewswire/ -- KaloBios Pharmaceuticals, Inc. (NASDAQ:KBIO) presented data from its Phase 1/2 study in persistent asthma for KB002 (precursor chimeric anti-GM-CSF monoclonal antibody to KB003) at the American Academy of Allergy, Asthma & Immunology (AAAI) Annual Meeting in Austin, Texas. The findings demonstrated preliminary safety, tolerability, and signs of activity of anti- GM-CSF antibodies in asthma and support continued development of the company's Humaneered ® KB003 anti-GM-CSF monoclonal antibody in severe asthma. KB003 is currently in a Phase 2 trial in severe asthma patients inadequately controlled by corticosteroids. (Logo: http://photos.prnewswire.com/prnh/20130225/MM66380LOGO) "These initial clinical results with KB002 in asthma are highly encouraging," said Nestor Molfino, Chief Medical Officer of KaloBios. "KB002 was well-tolerated, with no significant adverse events in the study population. When KB002 was added to patients' standard of care treatment, the study also showed a reduction in airway inflammation (eosinophils) and improvements in FEV 1 (a measure of lung function). Moreover, asthmatics with reversible FEV 1 at baseline showed greater FEV 1 responses than non-reversible patients. As a result, we are targeting this patient population in our ongoing Phase 2 KB003 study." Methodology and Results The KB002 Phase 1/2 asthma study, which screened over 50 patients to enroll both atopic (eosinophilic) and non-atopic (neutrophilic) asthma subjects, randomized 24 subjects (2:1, active treatment versus placebo). The objectives of the study primarily were to evaluate safety and tolerability, effects on sputum inflammatory markers, and lung function after a single dose of KB002. KB002 was found to be generally safe and well tolerated. Mean FEV 1 value for the active treatment group increased 120ml from baseline to day 42 and decreased 40ml for the placebo group. Of the 24 subjects enrolled (17 on KB002 and 7 on placebo), 59% on KB002 versus 29% on placebo had a >100ml FEV 1 increase at day 42. In addition, when patients were segmented retrospectively by the criteria of "reversibility," with reversible patients defined as having a >12% improvement in FEV 1 from baseline after a beta agonist, reversible patients on KB002 experienced a greater increase in FEV 1 from baseline at day 42 versus those on placebo. A majority of responders showed an FEV 1 improvement of more than 10%, which is a level that is generally accepted as clinically meaningful. At day 42, 78% of KB002-treated reversible subjects had at least a 100-mL increase in FEV 1 compared with 38% of KB002-treated nonreversible subjects, 33% of placebo-treated reversible subjects, and 25% of placebo-treated nonreversible subjects. A majority of KB002-treated patients who had an improvement in FEV 1 also had measureable antibody in the sputum in addition to a decrease in eosinophils or neutrophils at day 28. About KB002/ KB003 KB002 and KB003 are recombinant monoclonal antibodies designed to target and neutralize human granulocyte macrophage colony-stimulating factor (GM-CSF), with potential for use in inflammatory and autoimmune indications. GM-CSF is an important part of an inflammatory cascade that stimulates white blood cells (granulocytes, including eosinophils, neutrophils, and macrophages) and maintains them in an active state. However, as described in a number of scientific publications, excessive GM-CSF may be involved in tissue damage associated with inflammatory diseases including asthma.