This study aims to evaluate the efficacy of pirfenidone in chronic hypersensitivity pneumonitis. This study included 40 adult patients (≥ 18 years) with a diagnosis of chronic progressive hypersensitivity pneumonitis. The included patients were divided into 2 groups 20 patients in each one.

Group 1: will receive pirfenidone in addition to the conventional treatment Group 2: will be maintained on conventional treatment. Forced vital capacity (FVC),6 minutes walking test(6MWT), oxygen tension in the arterial blood (PaO2), and St. George's Respiratory Questionnaire (SGRQ ) were measured before and after 6 months of a pirfenidone treatment trial.

Results

Rationale The present data about the treatment of CHP are few and largely based on observational studies and expert opinion. It is suggested that pirfenidone may slow disease progression in cases of CHP as it has some anti-inflammatory in addition to antifibrotic effects.

Hypothesis Pirfenidone will slow disease progression in hypersensitivity pneumonitis patients

Research questions

1. Can pirfenidone slow disease progression in cases of CHP?
2. What about the safety of pirfenidone in cases of CHP?

This study aims to evaluate the efficacy of pirfenidone in chronic hypersensitivity pneumonitis.

Objectives

1. To compare the functional and radiological parameters between patients group who receive pirfenidone treatment and the patient group who receive conventional treatment: FVC, 6 minutes walking distance, the partial pressure of oxygen in arterial blood ( PaO2), Pulmonary artery systolic pressure, St.George's Respiratory Questionnaire(SGRQ Score) and Quantitative ILD score (QILD), by quantitative HRCT chest.
2. To compare the side effects between patients' group who receive pirfenidone treatment and the patient group who receive placebo treatment

Study design An interventional randomized controlled study

Inclusion Criteria:

• Patients ≥ 18 years old with a diagnosis of chronic progressive Hypersensitivity pneumonitis:
• >10% extent of fibrosis (eg, reticulation) on high-resolution CT (HRCT) scan
• Absolute decline in FVC% predicted >5% within the previous 6 months despite conventional treatment.

Exclusion Criteria:

• Pregnancy or breastfeeding period
• Patients with peptic ulcer, severe hepatic disease, severe kidney disease, severe cardiac disease, and patients with other chronic pulmonary diseases.
• Presence of active infection
• History of alcohol or drugs abuse
• Active smokers