Money and Control Influence Oncologists' Use of Biosimilars

Oncologists are less likely to prescribe biosimilars if there is potential for their practices to lose money or control over the preferred medication, according to study findings presented at ASCO20 Virtual, the annual meeting of the American Society of Clinical Oncology.

Another study showed very high recognition and knowledge of biosimilars among oncologists in Brazil, where biosimilars could make a difference, and noted utilization barriers that could be overcome with education.

Below is a summary of these findings.

US Oncologists' Willingness to Prescribe Biosimilars

Although biosimilars are a fast-growing class of therapeutic products that could lower health care costs, whether oncologists are likely to use them was a question that investigators set out to answer. They sought to understand providers’ willingness to prescribe biosimilars in place of the reference products for bevacizumab, trastuzumab, rituximab, and pegfilgrastim.¹

The study included 75 hospital-affiliated (46.7%) and community-based oncologists (53.3%) and was conducted in July 2019.

Physicians reported using originator products “often or always” 76% of the time; however, 60% said they believed they expected to prescribe a biosimilar often or always in the future. Additionally, 70% of providers rated the quality, safety and effectiveness of biosimilars for the 4 reference products to be the same or nearly equivalent.

Provided that payer coverage was not an issue, oncologists said they were more likely to prescribe biosimilars for new patients (85.3%) , but only 69.3% said they would prescribe biosimilars for existing patients (P = .019). Investigators said the top 3 drivers of biosimilar use were the patients’ out-of-pocket cost, value of reimbursement, and cost to practice.

Asked why providers would not switch from buy-and-bill practices, under which they order medicine from a wholesaler, to white-bagging, under which a specialty pharmacy ships the provider the medication, providers cited “control of the drug” (41.3%) and financial benefit to the provider’s practice (40%) as the top reasons why not.

Most of the oncologists (62.7%) worked in a for-profit practice, and 38.7% of primary practices included in the survey offered exclusive in-office dispensing.

Investigators concluded that “payment models for biosimilars in cancer must support practice economics.”

Barriers to Use of Trastuzumab Biosimilar in Brazil

Brazil approved its first biosimilar for oncology, the HER2-targeting antibody trastuzumab, in 2017, and in a study, oncologists were found to have a high amount of knowledge surrounding biosimilars. However, utilization of biosimilars was found to be lower than physician knowledge and confidence would suggest, according to the study.²

Investigators surveyed 144 Brazilian oncologists about their knowledge of an anti-HER2 biosimilar, the manufacturing process, costs, clinical trials related to biosimilar approval, drug efficacy, and safety. All respondents had 9 years of oncology practice with an average of 15 patients with HER2-positive breast cancer each month.

In total, 95% of oncologists reported knowing the definition of a biosimilar and 96% expressed confidence they could prescribe trastuzumab biosimilar without doubts about its equivalence to the reference product. However, 81% said they would prescribe the biosimilar to all patients, 82% said they would use it interchangeably with the reference product, and 63% said they would extrapolate, or use the biosimilar off label.

Brazil is highly industrialized but has low gross domestic product per capital, and so the ability to provide high-cost targeted therapies to its population is limited. This would make the country an ideal place to implement the cost-saving potential of biosimilars, the authors said.

“The opportunity of patient access with biosimilars is real and it is the oncologist’s duty to engage in medical education programs,” the authors wrote.

Specifically, more education is needed about pharmacovigilance (the process of studying the effects of drugs once they have been approved), clinical trials that support biosimilar approval, and extrapolation of biosimilar use, they said.

“This study could highlight a crucial need for greater strategies to educate physicians, to disseminate biosimilars, and provide more informed decision making,” they wrote.

For more biosimilars news from ASCO20 Virtual, click here.

References

1. Calan C, Johnson KA, Avalos-Reyes E. US oncologists’ perception of the efficacy, safety, and willingness to prescribe biosimilar cancer therapies. Presented at ASCO20 Virtual; May 30-31, 2020. Abstract e15213. meetinglibrary.asco.org/record/189711/abstract

2. Resende HM, Cardoso P, Marassi P, et al. Extrapolation of indications and drug interchangeability as barriers to use trastuzumab-dkst biosimilar in Brazil. Presented at ASCO20 Virtual; May 30-31, 2020. Abstract e13010. meetinglibrary.asco.org/record/188886/abstract