Safety and tolerability of the treatment with a bevacizumab biosimilar (Effivia ® ) in adult Mexican patients with cancer: a multicenter, observational, prospective clinical study

Alberto Alfonso Pimentel-Rentería¹David Cantu²Eliseo Neftalí De La Cruz³David Suárez⁴Manuel Rodulfo Segura⁵José Gustavo Núñez⁶Livan Delgado-Roche^7*

• ¹Hospital de Oncología, UMAE Centro Médico Nacional Siglo XXI. Instituto Mexicano del Seguro Social, Mexico, Mexico
• ²National Institute of Cancerology (INCAN), Mexico City, México, Mexico
• ³La Raza National Medical Center, Mexican Social Security Institute, Ciudad de Mexico, México, Mexico
• ⁴Hospital de Especialidades No. 1, UMAE Centro Médico Nacional del Bajío. Instituto Mexicano del Seguro Social, Guanajuato, Mexico
• ⁵Hospital de Especialidades, UMAE Centro Médico Nacional Ignacio García Téllez. Instituto Mexicano del Seguro Social, Yucatán, Mexico
• ⁶Hospital de Especialidades, UMAE Centro Médico Nacional Manuel Ávila Camacho. Instituto Mexicano del Seguro Social, Puebla, Mexico
• ⁷Laboratorios Liomont SA (Mexico), Mexico City, Mexico

Safety of biosimilars is of major relevance for patients and medical community. The aim of this study was to evaluate the safety and tolerability of a bevacizumab biosimilar alongside standard chemotherapy in adult patients with cancer. In addition, the impact on patients´ quality-of-life was assessed. This is an observational, multicenter, prospective, phase IV clinical study conducted from April 2022 to April 2024. Adult patients with metastatic cancer were enrolled after informed consent signing. Clinical history, adverse events, and quality of life data were recorded from source documents. Treatment regimens followed the Clinical Practice Guidelines and the Investigator criteria. Adult patients (n=82) were included, 65.8% (n=54) completed the full 6-cycle treatment, while 34.1% (n=28) meet the criteria for early discontinuation including disease progression (18.3%), voluntary withdrawal or dropout (7.3%), treatment availability or brand switching (4.9%), and serious adverse events (3.7%). The incidence of adverse events was aligned with prior trials, with 97.5% (n=80) of patients reporting at least one adverse event. The severity of adverse events was mild (86.7%, n=873), while 11.2% (n=113) were moderate and 2.1% (n=22) severe. Five serious adverse events occurred in four patients. The average ECOG score at the end of treatment was similar to the basal score (p>0.05). The treatment with the bevacizumab biosimilar Effivia ® was considered well tolerated with no additional safety concerns. The average quality-of-life remained stable during treatment. These findings contribute to the growing clinical evidence on the safe use of Effivia ® in real-world settings.