Opioid trial for COPD breathlessness halted early

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Male or female aged ≥ 40 years * Cigarette smoking history ≥10 pack years * Clinical diagnosis of severe to very severe COPD, i.e. post-β2-agonist FEV1 \<50% and FEV1/FVC \<0.70 * Chronic activity-related dyspnea, define as any one or combination of a modified MRC of 3-4 or a BDI focal score ≤ 8 * Uncontrolled daily activity-related dyspnea despite optimal medical treatment, including oral morphine treatment at a dose of a least 4 mg per day * No change in medication dosage or frequency of administration in the previous 2 weeks * No exacerbations or hospitalizations in the preceding 4 weeks Exclusion Criteria: * CO2 retention, defined as a resting arterial/capillary PCO2 of \>50 mmHg * Self-reported history of addiction/substance abuse * Acute alcoholism * Presence of important contraindications to cardiopulmonary exercise testing (CPET) * History of hypersensitivity to fentanyl or any component of the formulation * Actual use of methadone * Concurrent use or use within 14 days of a monoamine oxidase (MAO) inhibitor * Severe CNS depression * Convulsive disorders * Known or suspected mechanical GI obstruction (e.g., bowel obstruction or strictures) or any diseases/conditions that affect bowel transit (e.g., ileus of any type) * Increased cerebrospinal or intracranial pressure and head injury * Active mouth mucositis * Dementia diagnosis or significant neurocognitive problems * History of severe chronic kidney disease (stage 4-5) * Women of child bearing potential (defined as not having gone at least 12 months without a menstrual period) will be required to take a routine (urine) pregnancy test to rule out the possibility of pregnancy * Breast-Feeding women * Acute or unstable, clinically significant abnormal findings in physical exam, vital signs or ECG (as per Investigators opinion) * Patients receiving long-term treatment with Oxygen \>4.0 liters/minute (L/min). They must be ambulatory and be able to attend clinic visits. While breathing supplemental oxygen, they must demonstrate an oxyhemoglobin saturation ≥ 89%. * Malignancy, current or within the past 2 years. that the patient is not stable * Scheduled major surgical procedure during the course of the study