What are the Pulmonary Function Test (PFT) criteria for using Ensifentrine (RPL554) in patients with Chronic Obstructive Pulmonary Disease (COPD)?

Pulmonary Function Test Criteria for Ensifentrine in COPD

Ensifentrine is indicated for patients with moderate to severe COPD who have a post-bronchodilator FEV1 between 40-80% of predicted normal value with persistent symptoms despite standard therapy.

Diagnostic Criteria for Ensifentrine Eligibility

Required Spirometric Parameters

• Post-bronchodilator FEV1/FVC ratio <0.70 to confirm COPD diagnosis 1
• Post-bronchodilator FEV1 between 40-80% of predicted normal value 2, 3
• Evidence of persistent airflow limitation that is not fully reversible with bronchodilator testing 4

Patient Population Characteristics

• Age 40-80 years 2
• Symptomatic despite current therapy 2, 3
• Can be used as add-on therapy to:
  • Long-acting muscarinic antagonists (LAMA) 3
  • Long-acting beta-agonists with inhaled corticosteroids (LABA+ICS) 3

Assessment Process for Ensifentrine Candidacy

Step 1: Confirm COPD Diagnosis

• Post-bronchodilator spirometry showing FEV1/FVC <0.70 4, 1
• Presence of respiratory symptoms (dyspnea, chronic cough, sputum production) 4
• History of exposure to risk factors (primarily smoking) 4

Step 2: Assess Disease Severity

• Categorize COPD severity based on post-bronchodilator FEV1:
  • Moderate COPD: FEV1 50-69% predicted 4
  • Severe COPD: FEV1 40-49% predicted 4

Step 3: Evaluate Symptom Burden

• Assess symptoms using validated tools (e.g., COPD Assessment Test, modified Medical Research Council dyspnea scale)
• Document impact on quality of life
• Evaluate history of exacerbations

Clinical Considerations for Ensifentrine Use

Optimal Candidates

• Patients with moderate to severe COPD who remain symptomatic despite maintenance therapy 2, 3
• Patients with history of exacerbations who may benefit from ensifentrine's exacerbation reduction properties 5
• Patients on LAMA or LABA+ICS who need additional bronchodilation and anti-inflammatory effects 3

Monitoring Recommendations

• Perform baseline spirometry before initiating therapy
• Reassess lung function after 4-12 weeks to evaluate response 6
• Monitor for improvement in:
  • FEV1 (average improvement of 87-94 mL over placebo has been observed) 2
  • Respiratory symptoms
  • Quality of life measures
  • Exacerbation frequency

Common Pitfalls to Avoid

1. Inadequate diagnostic testing: Ensure post-bronchodilator spirometry is performed to confirm COPD diagnosis and avoid misdiagnosis 1

2. Relying solely on pre-bronchodilator values: Post-bronchodilator values are essential to confirm persistent airflow limitation 1

3. Overlooking comorbidities: Assess for conditions that may mimic or exacerbate COPD symptoms

4. Not considering exacerbation history: Ensifentrine has shown significant reduction in exacerbation rates and risk (41% reduction in rate and 41% reduction in risk compared to placebo) 5

5. Failure to optimize current therapy: Ensure patients are adherent to and properly using their current medications before adding ensifentrine

By following these PFT criteria and assessment steps, clinicians can appropriately identify patients with COPD who are most likely to benefit from ensifentrine therapy, potentially improving lung function, symptoms, quality of life, and reducing exacerbation risk.