This multicentre, prospective, observational study is designed to assess the real-world effectiveness and safety of Single Nebulizer Triple Therapy (SNTT) in Indian patients with chronic obstructive pulmonary disease (COPD) who are switched from Single Inhaler Triple Therapy (SITT DPI/pMDI) based on the treating physician’s clinical judgement. Adult patients aged more than or equal to 40 years with a confirmed diagnosis of COPD, as defined by GOLD 2026 criteria, who require transition to SNTT in routine clinical practice will be enrolled after obtaining written informed consent. The total study duration will be 12 weeks.

At screening and baseline, a detailed medical history, physical examination, vital signs assessment, spirometry, and dyspnea evaluation using the modified Medical Research Council (mMRC) scale will be conducted. Patient and physician satisfaction questionnaires will also be completed. Enrolled subjects will receive nebulized fixed-dose Glycopyrronium (25 µg), Formoterol (20 µg), and Budesonide (500 µg) administered twice daily via a jet nebulizer. Participants will be provided with a subject diary to record adverse events, rescue medication use, and treatment compliance.

Patients will attend routine follow-up visits, preferably at weeks 1, 2, 4, 8, and 12. Safety will be monitored throughout the study. At each visit, spirometry, clinical examination, vital signs assessment, review of adverse events, concomitant medications, compliance, and subject diaries will be performed. The mMRC score, patient and physician satisfaction, and the frequency of exacerbations, hospitalizations, and rescue medication use will be assessed and documented.