Factors influencing best tolerated dose of pirfenidone (PFD) in patients with IPF

Background: Not all patients with IPF tolerate full dose of PFD (2400mg/day). Aim: To identify factors influencing best tolerated dose of PFD in patients with IPF. Methods: 113 patients (58% males), mean age 65.5years included. PFD was initiated at 600 mg/day and escalated every 2 weeks with liver enzymes and adverse events monitoring to target 2400 mg/day. If escalated dose was not tolerated, previous best tolerated dose was continued. With availability of Nintedanib, switch option was given to patients not tolerating full dose of PFD. PFD is our first choice antifibrotic for IPF as it is generic and cheaper compared to nintedanib. Patients were divided in 4 groups:those tolerating 600mg (1 patient), 1200mg (45 patients), 1800mg (43 patients) and 2400mg (24 patients). Age, gender, height, weight, body mass index (BMI), body surface area (BSA), smoking and presence of comorbidities were compared between patients tolerating 2400mg with those tolerating Results: There was no statistically significant difference present in age, weight and BMI between 2400mg and Conclusion: Higher BSA and male gender were associated with tolerance of higher dose of PFD in our study population.