Physician Understanding and Willingness to Prescribe Biosimilars: Findings from a US National Survey

Obstacles to Biosimilar Acceptance and Uptake in Oncology: A Review

Importance

Biosimilar drugs provide cost-effective yet clinically indistinguishable replications of target drugs. During initial development, this class of biologic medicines was expected to revolutionize pharmaceutical markets; however, following US Food and Drug Administration approval of the first biosimilar drug in 2015, the commercialization of biosimilars has been limited. The lack of biosimilar use may be especially salient in oncology, given that biosimilar distribution in this particularly high-cost area of medicine would bring savings on the order of many billions of dollars.

Observations

While researchers have focused on salient economic barriers to biosimilar uptake in the US, the present review provides insight regarding noneconomic barriers. This review discusses psychological, attitudinal, and educational factors among both health care professionals and payers in the US that may play a role in slowing biosimilar uptake. More specifically, these factors include a lack of health care professional education, concerns of safety and efficacy, and overly complex product naming systems.

Conclusions and Relevance

The pathway to biosimilar use has been obstructed by economic elements as well as attitudinal and psychological factors. For biosimilar drugs to achieve their potential in decreasing treatment costs and thus increasing patient access, it will be essential for both economic and noneconomic factors to be identified and systematically addressed.

Barriers and Enablers Affecting the Uptake of Biosimilar Medicines Viewed Through the Lens of Actor Network Theory: A Systematic Review

BACKGROUND AND OBJECTIVE

Biosimilars represent an opportunity to realise savings against the costs of innovative medicines. Despite efforts made by stakeholders, there are numerous barriers to the uptake of biosimilars. To realise the promise of biosimilars reducing costs, barriers must be identified, understood, and overcome, and enablers magnified. The aim of this systematic review is to summarise the enablers and barriers affecting uptake of biosimilars through the application of a classification system to organise them into healthcare professional (HCP), patient, or systemic categories.

METHODS

A systematic literature search was performed in PubMed, Scopus, CINAHL, eConlit, and Embase. Included were primary research studies published in English between Jan 2017 through June 2023 focused on enablers and barriers affecting uptake of biosimilars. Excluded studies comprised comparisons of biosimilar efficacy and safety versus the reference biologic. One reviewer extracted data that included classification of barriers or enablers, the sub-classification, and the identification of the degree of agency associated with the actor through their role and associations as a mediator within their network, through the application of Actor Network Theory. The data were validated by a second reviewer (PV).

RESULTS

Of the 94 studies included, 59 were cross-sectional, 20 were qualitative research, 12 were cohort studies, and three were economic evaluations. Within the review, 51 of the studies included HCP populations and 35 included patients. Policies and guidelines were the most cited group of enablers, overall. Systemic enablers were addressed in 29 studies. For patients, the most frequently cited enabler was positive framing of a biosimilar, while for HCPs, cost benefit was the most frequently noted enabler. The most frequently discussed systemic barrier to biosimilar acceptance was lack of effective policies or guidelines, followed by lack of financial incentives, while the most significant barriers for HCPs and patients, respectively, were their lack of general knowledge about biosimilars and concerns about safety and efficacy. Systemic actors and HCPs most frequently acted with broad degree of agency as mediators, while patient most frequently acted with a narrow degree of agency as mediators within their networks.

CONCLUSIONS

Barriers and enablers affecting uptake of biosimilars are interconnected within networks, and can be divided into systemic, HCP, and patient categories. Understanding the agency of actors within networks may allow for more comprehensive and effective approaches. Systemic enablers in the form of policies appear to be the most effective overall levers in affecting uptake of biosimilars, with policy makers advised to give careful consideration to appropriately educating HCPs and positively framing biosimilars for patients.

Biosimilars: From Production to Patient

Biologic drugs are large, complex molecules produced through biotechnology. A biosimilar is a biologic product that is highly similar to an already approved biologic (reference product), with no clinically meaningful differences in purity, safety, or efficacy; as such, a biosimilar does not need to undergo the same level of study in a clinical trial program as the original reference product. Due to the potential impact of biosimilars on patient access and health care systems, the US Food and Drug Administration introduced an abbreviated pathway for approving biosimilars (351[k]) in 2009. There is strong evidence that switching from a reference product to a biosimilar does not reduce treatment effectiveness or increase the risk of adverse events. Biosimilars may reduce costs and increase patient access to biologic therapies. Biosimilar use in the United States has increased, as have the associated biosimilar cost savings, which are expected to reach $104 billion between 2020 and 2024. Yet, a need remains for increased knowledge among health care professionals and patients. Prescriber confidence is key to patient acceptance of biosimilars and minimizing the incidence of the nocebo effect. Infusion nurses are well positioned to help educate patients and to improve clinical outcomes across a range of diseases.

Filgrastim and infliximab biosimilar uptake in Medicare Advantage compared with Traditional Medicare, 2016-2019

BACKGROUND

Medicare Advantage (MA) and Traditional Medicare face different financing structures and incentives and may implement different strategies to encourage biosimilar uptake. Strategies used by health insurers can influence biosimilar uptake, which can in turn promote savings to insurers and patients.

OBJECTIVE

To compare filgrastim and infliximab biosimilar uptake between MA and Traditional Medicare from 2016 to 2019 and examine biosimilar uptake by different MA carriers and plan types (Health Maintenance Organization [HMO] or Preferred Provider Organization).

METHODS

We use a 2016-2019 nationally representative random 20% sample of the carrier (physician) and outpatient paid claims for Traditional Medicare data and final-action carrier and outpatient records for MA data. We compare quarterly biosimilar uptake from 2016 to 2019 for the first 2 drugs with biosimilar competition: (1) filgrastim, (Neupogen, originator), and biosimilars tbo-filgrastim (GRANIX) and filgrastim-sndz (ZARXIO), and (2) infliximab (Remicade, originator), and biosimilars infliximab-dyyb (Inflectra) and infliximab-abda (Renflexis).

RESULTS

From their introduction, there was consistently greater uptake of filgrastim and infliximab biosimilars in MA compared with Traditional Medicare. By Q4 2019, filgrastim biosimilar uptake was 7.6 percentage points higher in MA (80.3%) than Traditional Medicare (72.7%). By Q4 2019, infliximab biosimilar uptake was 28.7% and 15.4% in MA and Traditional Medicare, respectively. Kaiser HMO plans were primarily responsible for the higher uptake of biosimilars in MA; in Q4 2019, filgrastim and infliximab biosimilar uptake was 98.8% and 78.8%, respectively.

CONCLUSIONS

Our findings suggest that filgrastim and infliximab biosimilar uptake is greater in MA compared with Traditional Medicare, which is driven in part by particularly high uptake of biosimilars in MA Kaiser HMO plans. This highlights the need for future work to examine specific strategies and levers employed by MA Kaiser HMO plans and other insurers to increase biosimilar uptake, which can lead to cost savings for physician-administered drugs.

Biosimilars engage in low levels of direct-to-physician marketing relative to reference biologics

Biosimilars have the potential to greatly reduce US spending on biologic drugs, but uptake of these competitor products varies. We used Open Payments data from 2014 to 2022 to proxy for direct-to-physician marketing and compared levels of activity between biologic and biosimilar drug manufacturers. Our analysis focused on 6 reference biologics that recently faced competition in the years immediately before and after the launch of the first biosimilar. We used Medicare Part B dosage units to measure market penetration of biosimilars and its relationship with biosimilar marketing activity. Last, we conducted a sensitivity test, comparing payments for primarily office- or hospital-based physicians, using affiliations constructed from Medicare Carrier claims. Reference biologic manufacturers greatly reduced the amount of direct-to-physician marketing in the post-launch period. Biosimilar manufacturers generally engaged in low levels of activity relative to the historic performance of reference biologics. These trends were consistent across office- and hospital-based physicians. The intensity of biosimilars' direct-to-physician marketing also had no apparent relationship with achieved market penetration. Our findings demonstrate that persistently high market shares of reference biologics cannot be explained by ongoing direct-to-physician marketing activities. At the same time, while such activities could educate physicians or induce switching, biosimilar entrants engaged in little direct-to-physician marketing.

Real-World Clinical Outcomes of Bevacizumab-awwb Biosimilar versus Bevacizumab Reference Product in Patients with Metastatic Colorectal Cancer

BACKGROUND

Bevacizumab-awwb was the first biosimilar approved for cancer treatment in the USA. Limited information is available on the real-world comparative safety and effectiveness of bevacizumab biosimilars, especially for indications granted approval through extrapolation.

OBJECTIVE

To evaluate the real-world outcomes of patients with metastatic colorectal cancer (mCRC) initiated on bevacizumab-awwb versus bevacizumab reference product.

PATIENTS AND METHODS

This was an observational, longitudinal cohort study of US adult patients with mCRC from four integrated care delivery systems who were newly initiated on bevacizumab-awwb between 1 July 2019 and 30 March 2020 or bevacizumab reference product between 1 July 2015 and 30 June 2018. Patients were followed until 1 year after treatment initiation, end of plan membership, or death, whichever occurred first. The primary outcome of overall survival (OS) was analyzed using a binary non-inferiority test with lower margin of 10% and adjusted Cox proportional hazards regression analysis to assess all-cause mortality if non-inferiority was met. Secondary outcomes included counts of doses received, treatment duration, all-cause hospitalizations, and incidence of serious adverse events.

RESULTS

A total of 1445 patients initiated on either bevacizumab-awwb (n = 239) or bevacizumab reference product (n = 1206) were included in the analysis. The mean overall age was 60 ± 13 years, 46% of patients were female, and 51% were white. The OS rate was 72.8% and 73.1% for patients receiving bevacizumab-awwb and bevacizumab reference product, respectively (p < 0.01 for non-inferiority). The adjusted hazard ratio for mortality was 1.01 (0.77-1.33, p = 0.93). There were no statistically significant differences in secondary outcomes between the study groups.

CONCLUSIONS

These findings suggest that bevacizumab-awwb is as effective and safe as bevacizumab reference product for the real-world treatment of mCRC.

Improving patient access to biosimilar tumor necrosis factor inhibitors in immune-mediated inflammatory disease: lessons learned from Norway

INTRODUCTION

TNF inhibitors (TNFi) are in widespread use to treat a range of immune-mediated inflammatory diseases. However, the use of less expensive, biosimilar versions of these costly agents varies considerably around the world. Along with other Scandinavian countries, Norway has been successful in implementing the consistent clinical use of biosimilars rather than originator compounds.

AREAS COVERED

We discuss the implementation of biosimilar TNFi in Norway, explain how this work was carried out over the past 10 years and highlight factors that have been key in securing their acceptance and use. This implementation is discussed in relation to the situation in other countries.

EXPERT OPINION

The Norwegian tender and procurement system has been important to lower the cost of TNFi. Importantly, the emergence of biosimilar alternatives has lowered the cost not just of biosimilar TNFi but also originators due to competition. The involvement of the clinical communities through expert advisory boards has been important in securing acceptance of biosimilars early on. We suggest that the Norwegian procurement and tender system for biologic drugs may serve as a model for other countries, but has to be adjusted and modified according to specific national health-care systems and national contextual factors.

Switching from adalimumab originator to biosimilar: a 3-year retrospective cohort analysis

Our three year retrospective cohort study demonstrated that the vast majority of patients tolerated the switch from adalimumab originator to adalimumab biosimilar, with a 19% switchback rate. All patients who switched back to originator from biosimilar recovered from loss of efficiency and reported adverse events.

Physicians therefore should be confident in switching patients with well controlled psoriasis to adalimumab biosimilars.

Malaysian Hospital Pharmacists' Perspectives and Their Role in Promoting Biosimilar Prescribing: A Nationwide Survey

BACKGROUND

With the increasing availability biosimilars, the role of pharmacists as drug information specialists has expanded to include promoting biosimilar acceptance among prescribers.

OBJECTIVES

Our study aimed to determine Malaysian hospital pharmacists' perspectives on biosimilars and to identify factors influencing the successful promotion of biosimilars to prescribers.

METHODS

This was a cross-sectional, web-based survey of hospital pharmacists across Malaysia. Multivariate logistic regression analysis was used to identify factors associated with pharmacists successfully promoting biosimilar use.

RESULTS

Of the 913 responses, over 60% of pharmacists believed that patients may safely be switched from the originator product to a biosimilar and would have the same clinical outcome. Many lacked training in biosimilars (62.8%); yet most (80.6%) perceived pharmacists to play a critical role in promoting biosimilar prescribing. Multivariate logistic regression analysis showed that the strongest factor associated with pharmacists' successful promotion of biosimilars to prescribers was having confidence (odds ratio [OR], 3.33; 95% confidence interval [CI] 2.10-5.26). Respondents who had prior experience handling biosimilars were more likely to be successful in promoting biosimilar use than those without (OR, 1.76; 95% CI 1.16-2.66). The pharmacists' top perceived barrier to promote biosimilars in clinical practice was efficacy concerns.

CONCLUSION

Although Malaysian pharmacists are in favour of biosimilars, they lack training to promote biosimilar use. Among the factors associated with successful promotion of biosimilars to prescribers are pharmacist confidence, their previous experience handling biosimilars, and prior biosimilar training.

Identification of Barriers Preventing Biosimiliar Oncology Medication Adoption

(1) Background: A biosimilar is a biologic medical product that has been approved by the United States Food and Federal Drug Administration (FDA) and is an almost identical copy of an original biologic product yet manufactured by a different company. Biosimilars are often assumed to be the same as generic medications, while often made from living organisms. Through clinical trials, biosimilars have been shown to be both as safe and as effective as their originator products. Biosimilars have also proven they can reduce the costs to both insurance companies and patients in many circumstances. However, despite their cost savings, biosimilar manufacturers continue to face barriers in having oncologists and cancer centers prescribe them for their patients. This review aims to identify barriers associated with medical provider prescriptive behaviors related to biosimilars for patients. (2) Methods: Reviewers analyzed 27 articles and identified common themes. (3) Results: After a thorough literature review, the researchers identified seven barriers to prescribing of biosimilars: physician comfort in originators instead of biosimilars, patient reluctance to switch from a current biologic to a biosimilar, provider profits associated with an originator biologic, lack of stakeholder education on biosimilars, lack of provider team knowledge of biosimilars, lack of knowledge surrounding the biosimilar FDA approval process, and hesitancy to stock multiple drugs for a specific indication. (4) Conclusions: This review’s findings of identified barriers to use of biosimilars provides insight for healthcare providers and organizations surrounding prescribing practices and potential treatment benefits for cancer patients who may benefit from biosimilar treatment medications.

Pharmacists' Perspectives of Biosimilars: A Systematic Review

BACKGROUND AND OBJECTIVE

While biosimilars are less expensive than their originator biologics, various factors are known to impede their uptake in clinical practice including concerns regarding their interchangeability, efficacy, and safety. Pharmacists are well positioned to promote the adoption of biosimilars, thus, the aim of the review was to assess pharmacists' knowledge and perceptions of biosimilars to identify the need for pharmacist-directed biosimilar education.

METHODS

We conducted a systematic literature search for published articles indexed in MEDLINE via EBSCOHOST, Web of Science, Scopus, Cochrane Library, Dimensions, and Google Scholar databases. We included studies written in English from their earliest publication dates until December 2021. Only studies concerning pharmacists' perspectives on biosimilars were included. Two reviewers extracted data from the studies that included pharmacists' knowledge, perceptions, and opinions about interchangeability and automatic substitution of biosimilars. We also assessed the methodological quality of the included studies using the Joanna Briggs Institute Analytical Cross-Sectional Studies Assessment (JBI-ACSSA) for quantitative studies and the Critical Appraisal Skills Programme (CASP) for qualitative studies.

RESULTS

Out of the 22 studies included in the review, 19 were cross-sectional quantitative studies, and the other three were qualitative studies. The sample size of the included studies ranged from 19 to 1500 participants. The level of knowledge of biosimilars graded as good, considerable, above average, or excellent among pharmacists varied from study to study, with a range of 47-86%. Only 22-51% of pharmacists were comfortable if biosimilars were prescribed for all of the indications previously used for the originator products. Pharmacists' acceptability of switching from the originator to a biosimilar also varied, with a range of 26-84%. However, most pharmacists viewed the substitution of the originator with a biosimilar without physicians' permission as unacceptable. Data from three studies reported that 22-74% of pharmacists had attended biosimilar training. They obtained information about biosimilars from scientific publications, pharmaceutical companies, and continuing education. Based on the criteria of JBI-ACSSA and CASP, the overall methodological quality of the studies ranged from moderate to high. The majority of the studies did not describe the sampling methods used and the strategies to deal with confounding factors.

CONCLUSIONS

Pharmacists' knowledge and perception about biosimilars varied and were limited, especially about interchangeability and substitution, efficacy, safety, and indication extrapolation. A better understanding of biosimilars amongst pharmacists could help them to encourage prescribers' acceptance of biosimilars.

Patients Retransitioning from Biosimilar TNFα Inhibitor to the Corresponding Originator After Initial Transitioning to the Biosimilar: A Systematic Review

Background

Transitioning patients from an originator to a corresponding biosimilar has been extensively studied in both randomized controlled trials and observational studies. Although transitioning is considered well-tolerated, with no negative impacts on efficacy and/or safety, 2.6–25.8% of patients restart treatment with the originator (retransitioning). Retransitioning to the originator can be considered an indication of biosimilar treatment failure or dissatisfaction with biosimilar treatment. Increasing our knowledge of patients who retransition might help to reduce the number of patients retransitioning.

Objective

Our objective was to estimate the cumulative incidence of patients who retransitioned from a tumor necrosis factor (TNF)-α inhibitor biosimilar to originator and to explore potential patient, disease, and treatment and implementation strategy factors associated with retransitioning.

Method

We conducted a systematic literature search in the PubMed, EMBASE, and Cochrane Central Register of controlled trials databases until March 2021. Studies on TNFα inhibitors, biosimilar transitioning, and retransitioning were included. Transitioning was defined as switching from an originator to a biosimilar, and retransitioning was defined as switching from an originator to a biosimilar and back to the originator. Characteristics of the studies were descriptively analyzed. Studies were weighted by the number of patients transitioning, and the primary outcome was the median cumulative incidence of retransitioning. For each of the factors related to patient, disease, and treatment and implementation strategy, studies were stratified according to the categories of that factor. The weighted medians and interquartile ranges (IQRs) of the cumulative incidence of retransitioning in these studies were calculated and compared to explore whether a potential association existed between these factors and the cumulative incidence of retransitioning.

Results

Of 994 screened publications, 37 were included. The weighted median cumulative incidence of retransitioning was 7.6% (IQR 6.8–17.2). Studies that included only patients with inflammatory bowel disease (6.6 vs. 15.1–17.7% for other indications), included only patients with stable disease (7.0 vs. 13.7% for including all patients), and did not offer retransitioning at the introduction of the biosimilar (7.0 vs. 11.1% for studies that offered retransitioning) reported less retransitioning. In addition, the incidence of retransitioning was lower when extra laboratory monitoring was part of the implementation strategy (1.6 vs. 6.1%) and when gainsharing (patients’ healthcare directly benefits from financial savings from transitioning) (1.4 vs. 7.2% for studies without gainsharing) was applied.

Conclusions

In studies on transitioning patients from TNFα originator to biosimilar, 8% of patients retransitioned. Retransitioning appeared to be lower in studies that included only patients with stable disease and in studies that did not offer patients the option of retransitioning at the introduction of the biosimilar. In addition, retransitioning appeared to be lower in studies that implemented extra laboratory monitoring as part of the biosimilar implementation strategy. Clinicians should consider implementing these suggestions as they might reduce retransitioning rates and improve the introduction of biosimilars in clinical practice.

PROSPERO registration ID: CRD42021226381

Supplementary Information

The online version contains supplementary material available at 10.1007/s40259-021-00508-4.

Evolving Perceptions, Utilization, and Real-World Implementation Experiences of Oncology Monoclonal Antibody Biosimilars in the USA: Perspectives from Both Payers and Physicians

BACKGROUND

The adoption of oncology biosimilars has been slow in the USA, which may be attributed in part to stakeholder perceptions and lack of operational guidance that supports favorable access to biosimilars.

OBJECTIVE

Our objective was to understand the real-world implementation experiences with oncology biosimilars of US payers and healthcare professionals (HCPs) as their experience with biosimilars has evolved.

METHODS

In-depth qualitative interviews with payers (n = 20) and HCPs (n = 17 physicians, n = 3 practice managers) were conducted. Payers included managed care organizations (MCOs), integrated delivery networks, and pharmacy benefit managers (PBMs). Physicians were affiliated with a healthcare network or were community based, specialized in hematology/oncology, and had prescribed oncology biosimilars. Audio transcripts of the interviews were coded using MaxQDA software to enable descriptive analysis of the qualitative data.

RESULTS

Over 80.0% of physicians perceived the efficacy and safety of biosimilars to be highly comparable to that of originators. Up to 87.5% of physicians reported using biosimilars in > 50% of their treatment-naïve patients and were comfortable using biosimilars in all approved indications. To encourage utilization, 75.0% of MCOs/PBMs preferred biosimilars over originators in treatment-naïve patients and implementation via step therapy. Physician involvement in choosing biosimilars was minimal, which was largely dependent on practice protocols or insurance preferences. The major factor influencing payers' coverage decisions and biosimilar adoption was potential cost savings.

CONCLUSIONS

US payers and physicians who have experience with biosimilars have favorable views of oncology biosimilars, particularly for treatment-naïve patients. A framework for integrating biosimilars into oncology practice is developing, primarily driven by insurance coverage, contracting, and cost benefits.

Incidence of and Reasons and Determinants Associated with Retransitioning from Biosimilar Etanercept to Originator Etanercept

Background

Patients in clinical practice are transitioned from originator etanercept (OR-ETA) to biosimilar etanercept (BS-ETA), but some subsequently retransition. Insights into the incidence of and reasons for retransitioning and the characteristics of these patients could help clinicians successfully introduce biosimilars.

Objective

Our objective was to assess the incidence of and reasons for retransitioning from BS-ETA to OR-ETA in patients with a rheumatic disease (RD) and to explore the determinants thereof.

Methods

This cohort study included all patients with RD who had transitioned from OR-ETA to BS-ETA in a large hospital in the Netherlands in 2016. The incidence of retransitioning to OR-ETA and the 1-year persistence with BS-ETA were assessed using the Kaplan–Meier estimator. Reasons for retransitioning were classified as related to (1) efficacy, (2) adverse events, (3) the administration device, and (4) other. Determinants for retransitioning, including baseline and treatment characteristics, were assessed in a nested case–control study using conditional logistic regression.

Results

We included 342 patients (median age 57.8 years; 53.5% females). At 1 year after transitioning, 9.4% of patients had retransitioned to OR-ETA and 69.7% were persistent with BS-ETA. At the end of follow-up (median 4.4 years), 47 patients (13.7%) had retransitioned to OR-ETA. The median time until retransitioning was 0.55 years (interquartile range 0.2–1.3). Most patients (n = 34 [72.3%]) retransitioned because of a (perceived) loss of effect, followed by adverse events (23.4%). In total 3.8% of patients switched to another biological treatment or a Janus kinase inhibitor; 17.1% of patients discontinued BS-ETA without retransitioning or switching within the first year. Univariate determinants for retransitioning included initiating corticosteroids or intensifying immunomodulator treatment (odds ratio [OR] 2.37; 95% confidence interval [CI] 1.03–5.45) and the number of visits to the rheumatology department (OR 2.06; 95% CI 1.55–2.74). In the multivariate analysis, only the number of visits to the rheumatology department remained significantly associated with retransitioning (OR 2.19; 95% CI 1.60–3.01).

Conclusion

When introducing a biosimilar in clinical care, clinicians should anticipate that one in seven patients will retransition to the originator. A (perceived) loss of effect was the most frequently reported reason for retransitioning. Patients who visited the rheumatology department more frequently had an increased risk of retransitioning, which is likely to be related to patients reporting a loss of effect and to adverse events resulting in more visits to the rheumatology department.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40259-021-00501-x.