A Two Part, Randomised, Double-blind, Placebo-controlled, Phase 2 Parallel Group Study to Evaluate the Safety and Efficacy of Intravenously-Administered SelK2 on Airway Responses Following Allergen Challenge in Subjects with Asthma (Part 1) and to Evaluate the Safety and Efficacy of Intravenously-Administered SelK2 in Subjects with Chronic Obstructive Pulmonary Disease (Part 2)

INTERVENTION: Product Name: SelK2 Product Code: SelK2 Pharmaceutical Form: Solution for infusion INN or Proposed INN: Humanized anti‐PSGL‐1 monoclonal antibody Current Sponsor code: SelK2 Concentration unit: mg/ml milligram(s)/millilitre Concentration type: equal Concentration number: 10‐ Pharmaceutical form of the placebo: Solution for infusion Route of administration of the placebo: Intravenous use CONDITION: Part 1: Asthma Part 2: Chronic Obstructive Pulmonary Disease (COPD) ; MedDRA version: 20.0 Level: PT Classification code 10003553 Term: Asthma System Organ Class: 10038738 ‐ Respiratory, thoracic and mediastinal disorders ; MedDRA version: 21.1 Level: PT Classification code 10009033 Term: Chronic obstructive pulmonary disease System Organ Class: 10038738 ‐ Respiratory, thoracic and mediastinal disorders Therapeutic area: Diseases [C] ‐ Respiratory Tract Diseases [C08] PRIMARY OUTCOME: Main Objective: Part 1; Evaluate SelK2 for its ability to reduce the late asthmatic response (LAR) in terms of maximum percentage fall in FEV1 (forced expiratory volume in one second) after inhaled allergen challenge (breathing in a fine mist of the allergen that the participant is sensitive to).; ; Part 2; Evaluate the effect of SelK2 on neutrophil percentage in sputum (phelgm). Primary end point(s): Part 1:; •Maximum percentage fall in FEV1 from pre‐challenge between 3 and 8 hours (LAR) after administration of allergen inhalation challenge.; ; Part 2:; •Change from baseline in percentage of neutrophils in sputum on Day 22. Secondary Objective: Part 1 ‐ Secondary; •Evaluate SelK2 for its ability to reduce the LAR in terms of area under the curve (AUC) for the FEV1 after inhaled allergen challenge.; •Evaluate the effect of SelK2 on the eosinophil percentage in sputum.; •Evaluate the effect of SelK2 on the early asthmatic response (EAR) after inhaled allergen challenge.; •Evaluate the effect of SelK2 on the overall asthmatic response from 0‐8 hours after inhaled allergen challenge.; •Evaluate the effect of SelK2 on pre‐challenge FEV1.; •Evaluate the overall safety and tolerability of 2 doses of intravenous SelK2.; •Further describe the Pharmacokinetics (PK ‐ study drug levels and the time it takes for your body to break down the study drug) and Pharmacodynamics (PD; inhibition of PSGL‐1/P‐selectin binding) of SelK2 after giving 2 doses.; •Evaluate the immunogenicity (Human Anti‐Human Antibody [HAHA] response) following 2 doses of SelK2. To see if the body is making antibodies against the study medication.; ; Part 1 ‐ Exploratory; •Evaluat Timepoint(s) of evaluation of this end point: Part 1:; •FEV1 measured at Day 36 from pre‐allergen challenge and the period beginning 3 hours and ending 8 hours after the allergen challenge.; ; Part 2:; Days 22 SECONDARY OUTCOME: Secondary end point(s): Part 1 Secondary:; 1. AUC for the percent fall in FEV1 from pre‐challenge between 3 and 8 hours (LAR) after the administration of allergen inhalation challenge.; 2. Change from baseline and change during challenge in percentage of eosinophils in sputum measured at 8 and 24 hours post allergen challenge.; 3. Maximum percentage fall in FEV1 and AUC for the percent fall in FEV1 from pre‐challenge between 0 and 2 hours after the administration of allergen inhalation challenge (EAR).; 4. Maximum percentage fall in FEV1 and AUC for the percent fall in FEV1 between 0 and 8 hours (entire asthmatic response) after the administration of allergen.; 5. Change from baseline in pre‐challenge FEV1.; ; Part 1 Exploratory:; 6. Change from baseline and change during challenge in absolute and percentage cell counts for immune cells in induced sputum samples and blood (except for eosinophils in sputum which is a secondary endpoint).; 7. Change from baseline and change during challenge in fractional exhaled nitric oxide.; 8. Change from baseline and change during challenge in biomarkers of inflammation in both sputum and blood.; 9. Change in subject reported outcome as captured by Asthma Control Questionnaire 5‐Question Version (ACQ‐5) Score.; ; Part 2 Secondary:; 1. Change from baseline in percentage of neutrophils on Day 4, 8, 15, and 29.; 2. Change from baseline in absolute and percentage cell counts for immune cells in induced sputum samples and blood (except for neutrophils in sputum which is the primary endpoint) on Days 4, 8, 15, 22, 29.; 3. Change from baseline in FEV1 and post‐bronchodilator FEV1 on Days 4, 8, 15, 22, and 29.; 4. Change from baseline in pre‐ and post‐bronchodilator impulse oscillometry (IOS) on Days 4, 8, 15, 22, and 29.; 5. Change from baseline in pre‐ and post‐bronchodilator Whole body plethysmography on Days 4, 8, 15, 22, and 29.; 6. Change from baseline for subject reported outcomes: COPD Assessment Test (CAT) scores and Breathlessness Cough and Sputum Scale (BCSS) scores on Days 4, 8, 15, 22, and 29.; ; Part 2 Exploratory:; 7. Change from baseline in biomarkers of inflammation in both sputum and blood.; ; Part 1 and Part 2:; Safety:; Safety evaluations will include medical history, physical examinations, evaluation of AEs (including a general query such as “How do you feel?”), BMI, 12‐lead ECGs, vital signs (including tympanic temperature, respiratory rate, and supine blood pressure and pulse), spirometry, clinical laboratory evaluations; clinical chemistry (fasted at least 8 hours; water permitted), coagulation parameters (prothrombin time, activated partial thromboplastin time, international normalised ratio, D‐dimer), haematology, urinalysis, and pregnancy test (all female subjects).; ; PK, PD and Human Anti‐Human Antibodies (HAHA) Analyses:; Assessment of PK (sera concentrations of SelK2), PD (inhibition of PSGL‐1/P‐selectin binding), and immunogenicity (HAHA) for all subjects dosed with SelK2. Timepoint(s) of evaluation of this end point: Part 1; 1. Pre‐BAC & between 3‐8 hrs post‐BAC (Day 36); 2. Pre‐BAC, 8, 24 hrs post‐BAC (Day 36); 3. Pre‐BAC & between 0‐2 hrs post‐BAC (Day 36); 4. Pre‐BAC & between 0‐8 hrs post‐BAC (Day 36); 5. Pre‐BAC; 6, 8. Screen, Day 29, 8‐24 hrs post each BAC; 7. Screen, Days 1, 8, 15, 22, 29, 43, 57, pre‐BAC, 8‐24 hrs post each BAC; 9. Screen, Days 1, 8, 22, 36, 57; ; Part 2; 1. Screen, Days 4, 8, 15, 29; 2, 3, 4, 5, 6. Screen, Days 4, 8, 15, 22, 29; 7. Screen, Days 4, 8, 15, 22, 29, 43; ; Safety: All relevant time‐points as per protocol; PK/PD (Part 1): Day 1 (pre, 15, 30 mins, 1 hr), 2, 8, 15, 22 (pre, 15, 30 mins, 1hr), 23, 29, 36, 43, 50, 57; PK/PD (Part 2): Day 1 (pre, 1 hr), 4, 8, 15, 22, 29, 43; HAHA (Part 1): Day 1, 15, 22, 29, 43, 57; HAHA (Part2): Day 1, 22, 43 INCLUSION CRITERIA: Part 1: 1.Subject’s written informed consent obtained prior to any study‐related procedure. 2.Male or female, 18 to 65 years of age, inclusive, at the time of informed consent. 3.Female subjects must be either of non‐childbearing potential or if of childbearing potential use a highly effective birth control method (See Section 9.4.2). 4.Female subjects must agree not to donate ova/oocytes during the study and for 6 months after the last dose of investigational Medicinal Product (IMP). 5.Male subjects (with partners of child‐bearing potential) must use highly effective contraception (See Section 9.4.1). 6.Male subjects must agree not to donate semen during the study and for 3 months after the last dose of IMP. 7.Body Mass Index (BMI) = 18.0 and = 35.0 kg/m2 at Screening. 8.Documented physician‐diagnosed asthma for = 4 months prior to screening. 9.Pre‐bronchodilator FEV1 = 70% predicted at screening. 10.Documented allergy to at lea