Pirfenidone (Esbriet) is an important medication for the treatment of idiopathic pulmonary fibrosis (IPF). Developed by InterMune, it received approval from the U.S. Food and Drug Administration (FDA) for marketing in 2014. As a pyridone compound, pirfenidone improves lung function in IPF patients through its unique pharmacological effects.
Indications for Pirfenidone (Esbriet)
Primary Therapeutic Uses
Pirfenidone (Esbriet) is explicitly indicated for the treatment of idiopathic pulmonary fibrosis (IPF).
Idiopathic pulmonary fibrosis is a chronic, progressive, fibrotic interstitial pneumonia that primarily affects middle-aged and elderly individuals. Its pathological features include pulmonary parenchymal fibrosis and alveolar structural disorder, leading to progressive deterioration of lung function.
Clinical studies have confirmed that pirfenidone can slow down the rate of lung function decline in IPF patients and improve disease prognosis.
Dosage Forms, Specifications and Properties of Pirfenidone (Esbriet)
Basic Dosage Forms and Content
Pirfenidone (Esbriet) is available as hard capsules, with each capsule containing 267mg of the active ingredient pirfenidone.
The capsules are white, and the capsule cap is printed with "InterMune®" and "267mg" in brown ink for easy identification.
Ingredient Composition
In addition to the active ingredient pirfenidone, each capsule contains the following excipients: microcrystalline cellulose, croscarmellose sodium, povidone, and magnesium stearate.
The capsule shell is composed of gelatin and titanium dioxide, which ensures the stability and palatability of the medication.
The brown printing ink contains shellac, black iron oxide, red iron oxide, yellow iron oxide, propylene glycol, and ammonium hydroxide.
Chemical Properties
The chemical name of pirfenidone is 5-methyl-1-phenyl-2(1H)-pyridone, with a molecular formula of C₁₂H₁₁NO and a molecular weight of 185.23.
This compound is a white to pale yellow non-hygroscopic powder. It is more soluble in methanol, ethanol, acetone, and chloroform than in water and 1.0N hydrochloric acid (HCl), with a melting point of approximately 109°C.
Packaging Specifications
30-day supply bottle: Contains 270 capsules, sealed with a child-resistant cap.
14-day titration blister pack: Contains 63 capsules (21 single-capsule blisters for the first week and 42 double-capsule blisters for the second week).
4-week maintenance treatment blister pack: Contains 252 capsules (four blister cards, each with 63 triple-capsule blisters).
Dosage and Administration of Pirfenidone (Esbriet)
Initial Dosage and Titration Regimen
Days 1–7: 1 capsule (267mg) per dose, three times daily (total daily dose: 801mg).
Days 8–14: 2 capsules (534mg) per dose, three times daily (total daily dose: 1602mg).
From Day 15 onwards: 3 capsules (801mg) per dose, three times daily (total daily dose: 2403mg).
Administration Precautions
Timing of administration: The three daily doses should be taken at relatively fixed intervals; it is recommended to take them with breakfast, lunch, and dinner.
Dietary requirements: The medication must be taken with food, which can significantly reduce gastrointestinal adverse reactions such as nausea and dizziness.
Maximum dosage limit: The maximum recommended daily dose is 2403mg (9 capsules). Exceeding this dose will not increase efficacy and may increase the risk of adverse reactions.

