@article {WellsA178, author = {AU Wells and C Albera and U Costabel and I Glaspole and MK Glassberg and L Lancaster and DJ Lederer and CA Pereira and JJ Swigris and B-M Day and W Chou and SD Nathan}, title = {P174 Effect of continued treatment with pirfenidone following a >=10\% relative decline in percent predicted forced vital capacity (\%FVC) in patients with idiopathic pulmonary fibrosis (IPF)}, volume = {71}, number = {Suppl 3}, pages = {A178--A178}, year = {2016}, doi = {10.1136/thoraxjnl-2016-209333.317}, publisher = {BMJ Publishing Group Ltd}, abstract = {Background The variability in disease progression in patients with IPF complicates the assessment of treatment response. Previously a pooled analysis of three Phase 3 trials showed that patients who experienced a >=10\% absolute decline in \%FVC during the first 6 months of treatment derived a clinical benefit with continued pirfenidone treatment in the subsequent 6 months [Nathan et al. ATS 2015]. To further explore the potential benefit of continued pirfenidone treatment in patients who initially experienced more modest declines, we assessed subsequent outcomes after a >= 10\% relative decline in \%FVC during the first 6 months of treatment.Methods Source data included all patients randomised to receive pirfenidone 2403 mg/d or placebo in the ASCEND or CAPACITY trials (N = 1247). All patients with a >=10\% relative decline in\%FVC were selected by the 6-month study visit. The proportion of patients in the pirfenidone and placebo groups who experienced any of the following during the subsequent 6-month interval were compared: (1) >=10\% relative decline in\%FVC or death; (2) death; or (3) no further decline in \%FVC.Results Of the pooled patients that experienced an initial >=10\% relative decline in \%FVC, 80 and 140 patients received pirfenidone and placebo, respectively. In the subsequent 6 months, 17 (21.3\%) and 50 (35.7\%) patients, respectively, experienced a >= 10\% relative decline in \%FVC or death. In addition, more patients in the pirfenidone group had no further decline in \%FVC and fewer patients died compared with placebo during the subsequent 6-month interval (Table 1).Conclusions In patients who experienced a >=10\% relative decline in \%FVC during the first 6 months of treatment, continued treatment with pirfenidone appeared to lower the risk of \%FVC decline or death during the subsequent 6 months, similar to previous results observed with a >=10\% absolute \%FVC cut-off. Using relative change to calculate a >=10\% initial FVC decline identified more than twice as many patients compared to using absolute change. These findings suggest a potential benefit to continued treatment with pirfenidone despite an initial clinically meaningful decline in FVC >=10\% regardless of calculation method.View this table:Abstract P174 Table 1 Outcomes during the 6-month period following an initial >=10\% relative decline in \%FVC during the first 6 months of treatment}, issn = {0040-6376}, URL = {https://thorax.bmj.com/content/71/Suppl_3/A178}, eprint = {https://thorax.bmj.com/content/71/Suppl_3/A178.full.pdf}, journal = {Thorax} }