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OCID 2987: A Novel, Chemically Distinct Orally Active PDE4 Inhibitor
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Quantitative Differences in Treg Cells in Allergic Asthma: Impact of Site of Inflammation, Disease State and Medication Use P. E. Dahlberg, A. M. Singh, K. A. Burmeister, M. D. Evans, K. A. Roberg, J. E. Gern, C. M. Seroogy; University of Wisconsin Hospital and Clinics, Madison, WI. RATIONALE: The role of CD25+ T regulatory cells (Treg) in the pathophysiology of allergic asthma remains poorly defined. We sought to quantitate Treg cells in children with allergic asthma and developed a mouse model system for further interrogation of lung-specific Treg responses. METHODS: Blood from children enrolled in the Childhood Origins of ASThma study at the 7-8 year visit was analyzed by flow cytometry. An animal model of allergic pulmonary inflammation was established by intraperitoneal immunization of BALB/c mice with ovalbumin (OVA) + alum followed by intranasal OVA challenge. Lung and lymph node tissues were evaluated by flow cytometry. RESULTS: Tregs were defined as CD3+CD4+CD25+CD127lo/- and demonstrated the highest percentage of FoxP3 expression (80.0612.53%; n5151). Tregs were elevated in the bloodstream of children with asthma compared to non-asthmatics (6.9161.58% vs. 6.3361.60%; p50.054). In asthmatics, increased CD4+CD25+CD127lo/- T cells segregated with inhaled corticosteroid (ICS) use (7.3361.72% vs no asthma 6.9161.57%; p50.0097; vs asthma w/o ICS 6.5461.43%; p50.056). There was no statistical difference in the percentage of Foxp3+ cells or in the mean fluorescence intensity of Foxp3. A mouse model of allergic lung inflammation demonstrated an increase in Tregs in the lung (challenge 13.461.2% vs sham 8.28%61.35%; p50.008) but not in the peripheral lymphoid tissue after inhaled allergen challenge (11.462.2% vs sham 11.36 0.8%; p50.92). CONCLUSIONS: Together these data suggest that in allergic asthma Treg cell quantity is greatest at the sites of allergic inflammation such as the lung, and may be elevated in the circulation by disease severity or ICS use.
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OCID 2987: A Novel, Chemically Distinct Orally Active PDE4 Inhibitor S. Narayanan, S. Vishwakarma, S. Saxena, S. Honnegowda, K. Ganesan, F. A. Ahamed, N. Surendran, S. Narayanan, S. Rajagopal, G. Balasubramaniam; Orchid Research Laboratories Ltd, Chennai, INDIA. RATIONALE: Inhibition of PDE4 elevates cAMP because of which it is being actively explored as a target for the treatment of COPD and asthma. Recent marketing approval of roflumilast for treatment of COPD has opened the door for other potential PDE4 inhibitors. Method: OCID 2987 was evaluated in various invitro and ex vivo assays for COPD and asthma. OCID 2987 pharmacokinetic studies were done across species. OCID 2987 was screened in animal models - LPS induced endotoxemia and neutrophilia; cigarette smoke induced COPD; OVA induced asthma in guinea pig and BALB/c mice and for its emetic potential in ferret. RESULTS: OCID 2987 inhibited PDE4B2 enzyme at IC50 value of 8.23 nM and exhibited > 1000 fold selectivity over other PDE (PDE 1 to 11) isoforms. It has no effect on 150 biological targets screened. OCID 2987 showed potent inhibition of various cytokines in invitro assays. OCID 2987 showed oral bioavailability greater than 25% across species. OCID 2987 exhibited strong anti-inflammatory action in animal models of COPD and asthma with a wide safety margin for emesis. CONCLUSION: Our preclincal results suggest that OCID 2987 is a selective PDE4 inhibitor with good safety window and represents a novel PDE4 inhibitor to treat COPD and asthma. OCID 2987 is currently in regulatory toxicology studies.
195
Local Pollen Counts Correlate With Plasma Complement Levels And Peripheral Blood Complement Receptor Levels Of Adult Asthmatics Requiring Emergency Department Treatment R. Joks1, R. Shams1, M. S. Dzindzhikhashvili1, M. Watson1, S. Chice1, M. Nowakowski1, D. P. Erstein1, R. Sinert2, H. G. Durkin1; 1SUNY-Downstate Medical Center, Center for Allergy and Asthma Research, Brooklyn, NY, 2Kings County Hospital Center - Dept. of Emergency Medicine, Brooklyn, NY. RATIONALE: C5a and C3a are complement split product (CSP) anaphylatoxins formed by enzymatic cleavage by allergens and mast cell tryptase. As high pollen counts are associated with exacerbation of asthma, we determined the relation of pollen counts with plasma levels of C5a and C3a and peripheral blood leukocyte CSP receptor levels of adult asthmatics requiring emergency department (ED) treatment for an acute exacerbation. Methods. Blood was obtained from asthmatics (n550) requiring ED treatment for exacerbations during tree, grass, and ragweed seasons. Cells were studied within 6 hrs; plasma was separated and frozen at -70oC until assayed. The number of lymphocytes and monocytes 6C5a receptor (CD88) and C3a receptor (C3aR), plasma C5a desArg and C3a desArg, and absolute eosinophil counts were determined (flow cytometry, ELISA). Data are expressed in % total lymphocytes or monocytes, ng/ ml, and cells/mm3. Concurrent local grass, tree, and weed pollen counts were obtained, with permission, from the National Allergy Bureau and its participating station, Brooklyn, NY. Results. Grass pollen levels correlated with C5a desArg levels (p<0.01), monocyte CD88 (p50.04), and lymphocyte and monocyte C3aR (p<0.01 for both). Total, tree, and weed pollen counts all correlated with plasma C3a desArg levels (p50.02, p50.01, and p<0.01, respectively). Eosinophil counts correlated with grass pollen (p50.05), but not with other pollens or complement levels. Conclusions. Plasma levels of C5a desArg and C3a desArg and their peripheral blood cell receptor levels correlate with local pollen counts. These findings suggest that pollen allergen exposure is associated with complement mediated systemic inflammatory responses in allergic asthmatics.
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Montelucast (singulairÒ) Affects Bronchial And Nasal Reactivity Induced By Allergen Challenge A. Purohit1, M. Daniela1, M. Posa1, C. Bensoussan2, F. de Blay1; 1Division of Allergy and Asthma, Strasbourg, FRANCE, 2MSD France, Paris, FRANCE. RATIONALE: We intended to see the effect of SingulairÒ (Montelucast) on bronchial and nasal reactivity induced by bronchial and nasal challenges with cat allergen extract in cat allergic volunteers. METHODS: The volunteers underwent 4 sessions, 2 consisting bronchial and two nasal challenges. Each session needed three visit days D0, D6 and D7. On D0, NSBHR to methacholine was measured. Volunteers took the study drug, Singulair or placebo, from D0 to D6. On D6 challenge was performed. eNO was measured on D0, D6 (before and after challenge, 3 and 6 hours post challenge) and on D7 (24 hours post challenge). NSBHR was remeasured 3 hours post nasal challenge on D6. RESULTS: 26 volunteers participated in the study. Allergen BCT was evaluable in 25 volunteers. Fel d1 PD20 was significantly higher after the treatment with Singulair (2.464 mg) than with placebo (0.607 mg) (p <0.001) and eNO values were significantly lower immediately after, 3 and 6 hours post challenge. Allergen nasal challenge tests were evaluable in 23 volunteers. The dose inducing a positive reaction in terms of either reduction in nasal flow or increase in resistance was not different between two treatments. However, symptom score was significantly lower (p5 0.02) after Singulair than after placebo. The NSBHR did not modify after the nasal challenge and eNO values did not differ between two treatment groups. CONCLUSIONS: Singulair significantly reduces the bronchial reactivity. It significantly lowers the symptom score during nasal challenge. The NSBHR does not seem to modify after nasal allergen challenge.
SATURDAY
Abstracts AB49
J ALLERGY CLIN IMMUNOL VOLUME 125, NUMBER 2
Quantitative Differences in Treg Cells in Allergic Asthma: Impact of Site of Inflammation, Disease State and Medication Use P. E. Dahlberg, A. M. Singh, K. A. Burmeister, M. D. Evans, K. A. Roberg, J. E. Gern, C. M. Seroogy; University of Wisconsin Hospital and Clinics, Madison, WI. RATIONALE: The role of CD25+ T regulatory cells (Treg) in the pathophysiology of allergic asthma remains poorly defined. We sought to quantitate Treg cells in children with allergic asthma and developed a mouse model system for further interrogation of lung-specific Treg responses. METHODS: Blood from children enrolled in the Childhood Origins of ASThma study at the 7-8 year visit was analyzed by flow cytometry. An animal model of allergic pulmonary inflammation was established by intraperitoneal immunization of BALB/c mice with ovalbumin (OVA) + alum followed by intranasal OVA challenge. Lung and lymph node tissues were evaluated by flow cytometry. RESULTS: Tregs were defined as CD3+CD4+CD25+CD127lo/- and demonstrated the highest percentage of FoxP3 expression (80.0612.53%; n5151). Tregs were elevated in the bloodstream of children with asthma compared to non-asthmatics (6.9161.58% vs. 6.3361.60%; p50.054). In asthmatics, increased CD4+CD25+CD127lo/- T cells segregated with inhaled corticosteroid (ICS) use (7.3361.72% vs no asthma 6.9161.57%; p50.0097; vs asthma w/o ICS 6.5461.43%; p50.056). There was no statistical difference in the percentage of Foxp3+ cells or in the mean fluorescence intensity of Foxp3. A mouse model of allergic lung inflammation demonstrated an increase in Tregs in the lung (challenge 13.461.2% vs sham 8.28%61.35%; p50.008) but not in the peripheral lymphoid tissue after inhaled allergen challenge (11.462.2% vs sham 11.36 0.8%; p50.92). CONCLUSIONS: Together these data suggest that in allergic asthma Treg cell quantity is greatest at the sites of allergic inflammation such as the lung, and may be elevated in the circulation by disease severity or ICS use.
194
OCID 2987: A Novel, Chemically Distinct Orally Active PDE4 Inhibitor S. Narayanan, S. Vishwakarma, S. Saxena, S. Honnegowda, K. Ganesan, F. A. Ahamed, N. Surendran, S. Narayanan, S. Rajagopal, G. Balasubramaniam; Orchid Research Laboratories Ltd, Chennai, INDIA. RATIONALE: Inhibition of PDE4 elevates cAMP because of which it is being actively explored as a target for the treatment of COPD and asthma. Recent marketing approval of roflumilast for treatment of COPD has opened the door for other potential PDE4 inhibitors. Method: OCID 2987 was evaluated in various invitro and ex vivo assays for COPD and asthma. OCID 2987 pharmacokinetic studies were done across species. OCID 2987 was screened in animal models - LPS induced endotoxemia and neutrophilia; cigarette smoke induced COPD; OVA induced asthma in guinea pig and BALB/c mice and for its emetic potential in ferret. RESULTS: OCID 2987 inhibited PDE4B2 enzyme at IC50 value of 8.23 nM and exhibited > 1000 fold selectivity over other PDE (PDE 1 to 11) isoforms. It has no effect on 150 biological targets screened. OCID 2987 showed potent inhibition of various cytokines in invitro assays. OCID 2987 showed oral bioavailability greater than 25% across species. OCID 2987 exhibited strong anti-inflammatory action in animal models of COPD and asthma with a wide safety margin for emesis. CONCLUSION: Our preclincal results suggest that OCID 2987 is a selective PDE4 inhibitor with good safety window and represents a novel PDE4 inhibitor to treat COPD and asthma. OCID 2987 is currently in regulatory toxicology studies.
195
Local Pollen Counts Correlate With Plasma Complement Levels And Peripheral Blood Complement Receptor Levels Of Adult Asthmatics Requiring Emergency Department Treatment R. Joks1, R. Shams1, M. S. Dzindzhikhashvili1, M. Watson1, S. Chice1, M. Nowakowski1, D. P. Erstein1, R. Sinert2, H. G. Durkin1; 1SUNY-Downstate Medical Center, Center for Allergy and Asthma Research, Brooklyn, NY, 2Kings County Hospital Center - Dept. of Emergency Medicine, Brooklyn, NY. RATIONALE: C5a and C3a are complement split product (CSP) anaphylatoxins formed by enzymatic cleavage by allergens and mast cell tryptase. As high pollen counts are associated with exacerbation of asthma, we determined the relation of pollen counts with plasma levels of C5a and C3a and peripheral blood leukocyte CSP receptor levels of adult asthmatics requiring emergency department (ED) treatment for an acute exacerbation. Methods. Blood was obtained from asthmatics (n550) requiring ED treatment for exacerbations during tree, grass, and ragweed seasons. Cells were studied within 6 hrs; plasma was separated and frozen at -70oC until assayed. The number of lymphocytes and monocytes 6C5a receptor (CD88) and C3a receptor (C3aR), plasma C5a desArg and C3a desArg, and absolute eosinophil counts were determined (flow cytometry, ELISA). Data are expressed in % total lymphocytes or monocytes, ng/ ml, and cells/mm3. Concurrent local grass, tree, and weed pollen counts were obtained, with permission, from the National Allergy Bureau and its participating station, Brooklyn, NY. Results. Grass pollen levels correlated with C5a desArg levels (p<0.01), monocyte CD88 (p50.04), and lymphocyte and monocyte C3aR (p<0.01 for both). Total, tree, and weed pollen counts all correlated with plasma C3a desArg levels (p50.02, p50.01, and p<0.01, respectively). Eosinophil counts correlated with grass pollen (p50.05), but not with other pollens or complement levels. Conclusions. Plasma levels of C5a desArg and C3a desArg and their peripheral blood cell receptor levels correlate with local pollen counts. These findings suggest that pollen allergen exposure is associated with complement mediated systemic inflammatory responses in allergic asthmatics.
196
Montelucast (singulairÒ) Affects Bronchial And Nasal Reactivity Induced By Allergen Challenge A. Purohit1, M. Daniela1, M. Posa1, C. Bensoussan2, F. de Blay1; 1Division of Allergy and Asthma, Strasbourg, FRANCE, 2MSD France, Paris, FRANCE. RATIONALE: We intended to see the effect of SingulairÒ (Montelucast) on bronchial and nasal reactivity induced by bronchial and nasal challenges with cat allergen extract in cat allergic volunteers. METHODS: The volunteers underwent 4 sessions, 2 consisting bronchial and two nasal challenges. Each session needed three visit days D0, D6 and D7. On D0, NSBHR to methacholine was measured. Volunteers took the study drug, Singulair or placebo, from D0 to D6. On D6 challenge was performed. eNO was measured on D0, D6 (before and after challenge, 3 and 6 hours post challenge) and on D7 (24 hours post challenge). NSBHR was remeasured 3 hours post nasal challenge on D6. RESULTS: 26 volunteers participated in the study. Allergen BCT was evaluable in 25 volunteers. Fel d1 PD20 was significantly higher after the treatment with Singulair (2.464 mg) than with placebo (0.607 mg) (p <0.001) and eNO values were significantly lower immediately after, 3 and 6 hours post challenge. Allergen nasal challenge tests were evaluable in 23 volunteers. The dose inducing a positive reaction in terms of either reduction in nasal flow or increase in resistance was not different between two treatments. However, symptom score was significantly lower (p5 0.02) after Singulair than after placebo. The NSBHR did not modify after the nasal challenge and eNO values did not differ between two treatment groups. CONCLUSIONS: Singulair significantly reduces the bronchial reactivity. It significantly lowers the symptom score during nasal challenge. The NSBHR does not seem to modify after nasal allergen challenge.
SATURDAY
Abstracts AB49
J ALLERGY CLIN IMMUNOL VOLUME 125, NUMBER 2