A Study for GSK3862995B in Healthy Participants and Participants With Chronic Obstructive Pulmonary Disease

Inclusion Criteria: Healthy participants (Part A) * Participant must be 18 to 65 years of age inclusive. * Participants who are overtly healthy as determined by medical evaluation including medical history, physical examination, laboratory tests, and cardiac monitoring * Body weight within the range 50-110 kilogram (kg) (inclusive) * Body mass index (BMI) within the range 19.5-32 kilogram per square meter (kg/m\^2) * Male and/or female of non-childbearing potential Participants with Chronic Obstructive Pulmonary Disorder (COPD) (Part B) * Participant must be 40 to 75 years of age inclusive. * Body weight within the range 50-110 kg (inclusive) * BMI within the range 19.5-32 kg/m\^2 * Participant has a confirmed diagnosis of COPD for greater than (\>)12 months * Participants must present with a measured post-salbutamol Forced expiratory volume in 1 second/Forced vital capacity (FEV1/FVC) ratio of less than (\<) 0.70 at screening to confirm the diagnosis of COPD and a measured post-salbutamol FEV1 greater than or equal to (\>=) 40% of predicted normal values. * Participants must have a well-documented requirement for optimized standard of care background therapy that includes daily inhaled medication. * A peripheral blood eosinophil count of \>=150 cells/microliter (mcL) at screening * Former cigarette smokers with a history of cigarette smoking of \>=10 pack-years at screening current smokers (includes the use of any type of nicotine containing product), or non-smokers are …