{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,8]],"date-time":"2026-08-08T04:45:01Z","timestamp":1786164301603,"version":"build-2736575974"},"reference-count":27,"publisher":"Springer Science and Business Media LLC","issue":"5","license":[{"start":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T00:00:00Z","timestamp":1776384000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T00:00:00Z","timestamp":1776384000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Universit\u00e0 degli Studi di Modena e Reggio Emilia"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Intern Emerg Med"],"published-print":{"date-parts":[[2026,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>\n                      Generic formulations of pirfenidone are increasingly adopted in idiopathic pulmonary fibrosis (IPF), yet real-world evidence supporting their clinical equivalence to the originator remains limited. We aimed to evaluate whether switching from branded pirfenidone (Esbriet\n                      <jats:sup>\u00ae<\/jats:sup>\n                      ) to a generic formulation affects treatment efficacy or tolerability.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We conducted a retrospective, within-patient observational study including consecutive patients with IPF treated with Esbriet\n                      <jats:sup>\u00ae<\/jats:sup>\n                      for\u2009\u2265\u20096\u00a0months before switching to generic pirfenidone. Pulmonary function was assessed at three time points: 6\u00a0months before the switch (T\u2009\u2212\u20096), at switch (T0), and 6\u00a0months after (T\u2009+\u20096). The primary endpoint was the within-patient percentage change in FVC over two consecutive 6-month periods (T\u2009\u2212\u20096\u2009\u2192\u2009T0 vs T0\u2009\u2192\u2009T\u2009+\u20096), analysed within a pre-specified equivalence framework (\u00b1\u20095 percentage points). Secondary endpoints included DLCO changes and treatment-related adverse events (AEs), analysed at the patient level using paired comparisons.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Sixty-five patients (median age 77.0\u00a0years [72.3\u201380.0] years, 78% male) had complete functional follow-up. The mean percentage decline in FVC was\u2009\u2212\u20091.9% before the switch and\u2009\u2212\u20091.7% after the switch. The estimated between-period difference in FVC change was 0.2 percentage points (95% CI\u2009\u2212\u20091.1 to 1.5), fully contained within the pre-specified equivalence margins. Similar findings were observed for DLCO, with no significant difference between periods. Overall, 43% of patients experienced at least one AE during treatment. Gastrointestinal AEs were the most frequent, but paired analyses showed no significant difference in patient-level AE occurrence between branded and generic periods. No severe AEs or treatment discontinuations were observed.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In this real-world cohort of patients with IPF, switching from branded to generic pirfenidone was not associated with clinically meaningful differences in lung function decline or treatment tolerability.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s11739-026-04343-9","type":"journal-article","created":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T04:56:40Z","timestamp":1776401800000},"page":"1625-1633","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Efficacy and tolerability of generic pirfenidone after switch from Esbriet\u00ae in idiopathic pulmonary fibrosis: a real-world observational study"],"prefix":"10.1007","volume":"21","author":[{"given":"Roberto","family":"Tonelli","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Giulia","family":"Turchiano","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonio","family":"Moretti","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dario","family":"Andrisani","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filippo","family":"Gozzi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giulia","family":"Raineri","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna Valeria","family":"Samarelli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Federica","family":"Andolfi","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Valentina","family":"Ruggieri","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1515-5094","authenticated-orcid":false,"given":"Enrico","family":"Clini","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefania","family":"Cerri","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,4,17]]},"reference":[{"issue":"9","key":"4343_CR1","doi-asserted-by":"publisher","first-page":"e18","DOI":"10.1164\/rccm.202202-0399ST","volume":"205","author":"G Raghu","year":"2022","unstructured":"Raghu G, Remy-Jardin M, Richeldi L et al (2022) Idiopathic pulmonary fibrosis (an update) and progressive pulmonary fibrosis in adults: an official ATS\/ERS\/JRS\/ALAT clinical practice guideline. 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After using this tool\/service, the authors reviewed and edited the content as needed and take full responsibility for the content of the publication.","order":4,"name":"Ethics","label":"Generative AI and AI-assisted technologies in the writing process","group":{"name":"EthicsHeading","label":"Declarations"}}]}}