{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T15:52:21Z","timestamp":1780415541124,"version":"3.54.1"},"reference-count":17,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2024,3,21]],"date-time":"2024-03-21T00:00:00Z","timestamp":1710979200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Pan Canadian Biosimilar Initiative"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Current Oncology"],"abstract":"<jats:p>Background: Ontario publicly funds reference trastuzumab (Herceptin) and four biosimilar trastuzumab products for adjuvant treatment of HER2+ breast cancer. We assessed the real-world safety and effectiveness of biosimilar trastuzumab compared to Herceptin for adjuvant treatment of patients with HER2+ breast cancer. Methods: This was a population-based, retrospective study comparing the safety and effectiveness of biosimilar trastuzumab and Herceptin for neoadjuvant\/adjuvant treatment of HER2+ breast cancer from 2016 to 2021. Treatment patients started biosimilar trastuzumab from November 2019 to June 2021; historical comparator patients started Herceptin from June 2016 to October 2019. Safety outcomes death within 30 days of last dose of trastuzumab, direct hospitalization, emergency department visit leading to hospitalization, early treatment discontinuation, and in-patient admission for congestive heart failure were measured using logistic\/negative binomial regression. Overall survival (OS) was measured using Kaplan\u2013Meier methods and Cox proportional hazards regression. Propensity score matching was applied. Results: From June 2016 to 2021, 5071 patients with breast cancer were treated with neoadjuvant\/adjuvant trastuzumab. The rate of direct hospitalization (RR: 0.85, 95% CI: 0.74\u20130.98, p-value: 0.032) was significantly lower in biosimilar compared to Herceptin patients. OS (log-rank test p = 0.98) and risk of mortality (HR: 1.29, 95% CI: 0.72\u20132.30, p-value = 0.39) did not significantly differ between treatment groups. Conclusions: Biosimilar trastuzumab demonstrated similar safety and effectiveness to Herceptin. The findings can help improve confidence in and use of biosimilars and demonstrate the value of real-world evidence generation for supporting biosimilar implementations and reassessments.<\/jats:p>","DOI":"10.3390\/curroncol31030124","type":"journal-article","created":{"date-parts":[[2024,3,21]],"date-time":"2024-03-21T06:35:30Z","timestamp":1711002930000},"page":"1633-1644","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Comparative Effectiveness and Safety of Trastuzumab Biosimilars to Herceptin for Adjuvant Treatment of HER2+ Breast Cancer"],"prefix":"10.3390","volume":"31","author":[{"given":"Caroline","family":"Mu\u00f1oz","sequence":"first","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"},{"name":"Canadian Centre for Applied Research in Cancer Control, Toronto, ON M5G 2L3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaochen","family":"Tai","sequence":"additional","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica","family":"Arias","sequence":"additional","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrea","family":"Eisen","sequence":"additional","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"},{"name":"Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Munaza","family":"Chaudhry","sequence":"additional","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8635-6889","authenticated-orcid":false,"given":"Scott","family":"Gavura","sequence":"additional","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kelvin K. W.","family":"Chan","sequence":"additional","affiliation":[{"name":"Ontario Health (Cancer Care Ontario), 525 University Ave, Toronto, ON M5G 2L3, Canada"},{"name":"Canadian Centre for Applied Research in Cancer Control, Toronto, ON M5G 2L3, Canada"},{"name":"Sunnybrook Health Sciences Centre, Toronto, ON M4N 3M3, Canada"},{"name":"Temerty Faculty of Medicine, University of Toronto, Toronto, ON M5S 1A8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"707","DOI":"10.1126\/science.2470152","article-title":"Studies of the HER-2\/Neu Proto-Oncogene in Human Breast and Ovarian Cancer","volume":"244","author":"Slamon","year":"1989","journal-title":"Science"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"191","DOI":"10.1186\/s13643-018-0854-y","article-title":"Herceptin\u00ae (trastuzumab) in HER2-positive early breast cancer: A systematic review and cumulative network meta-analysis","volume":"7","author":"Wilson","year":"2018","journal-title":"Syst. 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Open"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"e7","DOI":"10.1016\/j.clon.2021.08.009","article-title":"Real-world Safety of Bevacizumab with First-line Combination Chemotherapy in Patients with Metastatic Colorectal Cancer: Population-based Retrospective Cohort Studies in Three Canadian Provinces","volume":"34","author":"Beca","year":"2022","journal-title":"Clin. Oncol. (R. Coll. Radiol.)"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1877","DOI":"10.3390\/curroncol29030153","article-title":"Assessing the Impact of the COVID-19 Pandemic on Emergency Department Use for Patients Undergoing Cancer-Directed Surgeries","volume":"29","author":"Eskander","year":"2022","journal-title":"Curr. Oncol."}],"container-title":["Current Oncology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1718-7729\/31\/3\/124\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T14:17:04Z","timestamp":1760105824000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1718-7729\/31\/3\/124"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,3,21]]},"references-count":17,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2024,3]]}},"alternative-id":["curroncol31030124"],"URL":"https:\/\/doi.org\/10.3390\/curroncol31030124","relation":{},"ISSN":["1718-7729"],"issn-type":[{"value":"1718-7729","type":"electronic"}],"subject":[],"published":{"date-parts":[[2024,3,21]]}}}