Building trust on biosimilars: Continuous safety surveillance of a biosimilar Bevacizumab (BEVAX®) in Argentina

Introduction and study objectives: The evaluation of the benefit-risk ratio of a drug is essential throughout its whole life cycle to guarantee that therapeutic efficacy for the authorized indications of the drug occur along with a reasonable incidence of adverse effects. Thus, a positive benefit-risk assessment for biosimilars arises also as a mandatory requirement. Bevax® (bevacizumab) is a biosimilar approved in Argentina since June 2016 developed from the originator Avastin® as the reference product. Since first launched in Argentina in November 2016, Bevax® has been subjected to an active pharmacovigilance program directed to assess the incidence of adverse effects related to the product’s use. This study aimed to summarize and evaluate the data from the post-marketing use of Bevax® contained in a treatment registry surveillance database established as part of a first step of the pharmacovigilance program for this product.
Methods: Health care professionals were asked to register details concerning patient, treatment, suspected adverse drug reactions, seriousness, and patient’s outcome for each of the patients treated with Bevax® in order to be included in the treatment registry surveillance database for the product. All adverse events were coded and grouped according the Medical Dictionary for Regulatory Activities (MedDRA version 21.0). Subsequently, the data recorded in the treatment registry for Bevax® in Argentina during the period from November 2016 to May 2018 were prospectively recovered and analyzed.
Results: A total of 818 registry forms corresponding to patients who initiated Bevax® treatment were collected. Of them, follow-up data were available for 416. A total of 51 adverse events (26 serious) were received corresponding to 44 individual case safety reports. The adverse events most frequently reported concerned the deterioration of the underlying disease (neoplasm progression) with 15 events followed by hypertension with five events. The remaining adverse events occurred generally as single events without evidence of any specific pattern. Of interest, off-label use of Bevax® was reported in 11 cases. Death was reported in 20, although in the majority of cases it was related to neoplasm progression. Discussion: Safety profile of Bevax® appears in line with previous published information concerning bevacizumab. The adverse events collected for Bevax® were, as expected, in concordance with those of the reference product. Data analysis showed that Bevax® was mostly used for approved indications, however there was an off-label use for no authorized indications in a small number of cases, without a specific predominance or pattern.
Conclusion: To the best of our knowledge, this is the first published report summarizing the adverse effects associated with the use of a biosimilar from post-marketing experience, showing the utility of developing active pharmacovigilance activities to increment knowledge about safety of biosimilars and therefore, for best rational use of these products.

Subscribe now to GaBI Journal to view full information of this article to be published in the next journal issue.

Source URL:

Generics and Biosimilars Initiative (GaBI)
Tel: +32 474989572 | Fax: +32 14 583 048