Totality of evidence in the development of ABP 215, an approved bevacizumab biosimilar

Real-world outcomes among patients with metastatic colorectal cancer treated first line with a bevacizumab biosimilar (bevacizumab-awwb)

Background

Bevacizumab-awwb (MVASI®) was the first U.S. Food and Drug Administration-approved biosimilar to Avastin® (reference product [RP]) for the treatment of several different types of cancers, including metastatic colorectal cancer (mCRC), an indication approved based on extrapolation.

Objectives

Evaluate treatment outcomes in mCRC patients who received first-line (1L) bevacizumab-awwb at treatment initiation or as continuing bevacizumab therapy (switched from RP).

Design

A retrospective chart review study.

Methods

Adult patients who had a confirmed diagnosis of mCRC (initial presentation of CRC on or after 01 January 2018) and initiated 1L bevacizumab-awwb between 19 July 2019 and 30 April 2020 were identified from the ConcertAI Oncology Dataset. A chart review was conducted to evaluate patient baseline clinical characteristics and effectiveness and tolerability outcomes during the follow-up. Study measures were reported stratified by prior use of RP: (1) naïve patients and (2) switchers (patients who switched to bevacizumab-awwb from RP without advancing the line of therapy).

Results

At the end of study period, naïve patients (n = 129) had a median 1L progression-free survival (PFS) of 8.6 months [95% confidence interval (CI), 7.6-9.9] and a 12-month overall survival (OS) probability of 71.4% (95% CI, 61.0-79.5%). Switchers (n = 105) had a median 1L PFS of 14.1 months (95% CI, 12.1-15.8) and a 12-month OS probability of 87.6% (95% CI, 79.1-92.8%). During treatment with bevacizumab-awwb, 20 events of interest (EOIs) were reported in 18 naïve patients (14.0%) and 4 EOIs reported in 4 switchers (3.8%), of which the most commonly reported events were thromboembolic and hemorrhagic events. Most EOIs resulted in emergency department visit and/or treatment hold/discontinuation/switch. None of the EOIs resulted in death.

Conclusion

In this real-world cohort of mCRC patients who were treated 1L with a bevacizumab biosimilar (bevacizumab-awwb), the clinical effectiveness and tolerability data were as expected and consistent with previously published findings from real-world studies of bevacizumab RP in mCRC patients.

Systemic Bevacizumab for Severe Recurrent Respiratory Papillomatosis

Recurrent respiratory papillomatosis (RRP) is the most common benign pediatric laryngeal neoplasm. Various adjuvant medical therapies have failed to reliably decrease surgical frequency in this challenging airway disease. Recently, systemic bevacizumab has shown promise in advanced, treatment-resistant papillomatosis. We describe the use of systemic bevacizumab in two children with severe RRP unresponsive to other therapies. Voice and breathing improved dramatically in both patients with minimal side effects. Both patients have not required surgery in 24 months and 16 months, respectively. Systemic bevacizumab is a promising long-term treatment for severe RRP, with oncology playing an important role in patient care.

Retrospective Indication-Matched Cohort Study of Reference Product and Biosimilar: Bevacizumab Versus Bevacizumab-Awwb

Introduction: Due to the abbreviated approval pathway and extrapolation to non-studied indications, an increased importance is placed on post-marketing surveillance of biosimilars to supplement existing evidence and enhance patient and provider confidence. Bevacizumab-awwb (ABP 215, Mvasi) was the first biosimilar approved to bevacizumab (Avastin), a recombinant humanized monoclonal IgG1 antibody that inhibits the vascular endothelial growth factor (VEGF). Purpose: To evaluate utilization, safety, and financial outcomes of bevacizumab-awwb compared to bevacizumab at a national cancer institute (NCI)-designated cancer center. Methods: A single center, retrospective, 1:1 indication-matched cohort study of adult patients who received bevacizumab or bevacizumab-awwb between October 1, 2019 and October 1, 2020 was performed. Thirty-four patients received bevacizumab-awwb during the study period and were matched by indication to 34 randomly selected patients who received bevacizumab. Indications for both groups included: colorectal cancer (n = 19), gynecologic cancer (n = 10), glioblastoma (n = 3), hepatocellular carcinoma (n = 1), and lung cancer (n = 1). Results: Baseline and medication utilization characteristics were similar for this indication-matched cohort of 68 patients receiving bevacizumab-awwb or bevacizumab. Patients in the bevacizumab group had a higher proportion of public payer coverage (64.7% vs 38.2%, P = .029). A higher proportion of patients in the bevacizumab-awwb group remained on active treatment at the end of the study period (52.9%) as compared to the bevacizumab group (35.3%); however, differences in final treatment status and reasons for discontinuation were not statistically significant (P = .218). Rates of worsened hypertension (44.1% vs 44.1%) and worsened proteinuria (38.2% vs 23.5%, P = .077) were common in both groups. Grade 3 adverse drug events in the bevacizumab group included: gastrointestinal perforation (n = 1), gastrointestinal bleed (n = 1), hypertension (n = 2), and venous thromboembolism (n = 2). Grade 3 adverse drug events in the bevacizumab-awwb group included: epistaxis (n = 1), gastrointestinal bleed (n = 1), hypertension (n = 1), intracerebral hemorrhage (n = 1), venous thromboembolism (n = 3), and arterial thromboembolism (n = 1). One patient in the bevacizumab-awwb group experienced grade 4 hypertension. Median drug cost per dose and per milligram for bevacizumab-awwb was less than bevacizumab, representing a 15.8% and 12.1% discount, respectively. Conclusion: Utilization and safety outcomes were similar for this indication-matched cohort of 68 patients receiving bevacizumab or bevacizumab-awwb across a wide range of disease states.

A review of the totality of evidence supporting the development and approval of a pegfilgrastim biosimilar (LA-EP2006)

OBJECTIVE

The totality-of-evidence approach requires that similarity between a proposed biosimilar and a reference biologic is demonstrated across a range of analytical, preclinical, and clinical parameters to establish biosimilarity. We describe the totality of evidence for Sandoz biosimilar pegfilgrastim (LA-EP2006 [marketed as Ziextenzo]) that supported its regulatory approval in Europe and the United States.

METHODS

Analytical similarity to the reference biologic [marketed by Amgen as Neulasta] was first investigated with regard to physiochemical quality attributes such as primary structure, pegylation, higher-order structures, variants and impurities, molecular size variants, and formulation (protein content, pH, excipients, etc.). In vitro biological activity studies were performed to examine the primary mechanism of action of pegfilgrastim. Bioequivalence (clinical pharmacokinetics [PK] and pharmacodynamics [PD]) of Sandoz biosimilar pegfilgrastim to the reference biologic was studied in healthy volunteers; efficacy, safety, and immunogenicity were assessed during confirmatory clinical efficacy studies in patients undergoing treatment for breast cancer.

RESULTS

No meaningful or relevant differences were identified between Sandoz biosimilar pegfilgrastim and the reference biologic during analytical testing. Similar receptor binding and induction of cellular proliferation in vitro confirmed no functional differences between the biologics. Clinical studies in healthy adult participants demonstrated PK/PD biosimilarity and a similar safety profile between biosimilar and reference pegfilgrastim. Clinical studies in a sensitive patient population also demonstrated similar efficacy, safety, and immunogenicity between Sandoz biosimilar pegfilgrastim and the reference biologic.

CONCLUSIONS

The totality of evidence confirms that Sandoz biosimilar pegfilgrastim matches the reference biologic and will therefore provide equivalent efficacy and safety in all eligible indications.

Phase III double-blind study comparing the efficacy and safety of proposed biosimilar MYL-1402O and reference bevacizumab in stage IV non-small-cell lung cancer

Purpose:

This phase III study compared the efficacy and safety of proposed biosimilar MYL-1402O with reference bevacizumab (BEV), as first-line treatment for patients with stage IV non-squamous non-small-cell lung cancer.

Patients and methods:

Patients were randomly assigned (1:1) to receive MYL-1402O or bevacizumab with carboplatin-paclitaxel up to 18 weeks (6 cycles), followed by up to 24 weeks (8 cycles) of bevacizumab monotherapy. The primary objective was comparison of overall response rate (ORR), based on independently reviewed best tumor responses as assessed during the first 18 weeks. ORR was analyzed per US Food and Drug Administration (ratio of ORR) and European Medicines Agency (difference in ORRs) requirements for equivalence evaluation. Secondary end points included progression-free survival, disease control rate, duration of response, overall survival, safety, and immunogenicity over a period of 42 weeks, and pharmacokinetics (up to 18 weeks).

Results:

A total of 671 patients were included in the intent-to-treat population. The ratio of ORR was 0.96 [confidence interval (CI) 0.83, 1.12] and the difference in ORR was −1.6 (CI −9.0, 5.9) between treatment arms; CIs were within the predefined equivalence margins. Overall, the incidence of treatment-emergent adverse events and serious adverse events was comparable. Treatment-emergent anti-drug antibody (ADA) positivity was transient, with no notable differences between treatment arms (6.5% versus 4.8% ADA positivity rate in MYL-1402O versus BEV, respectively). The incidence of neutralizing antibody post-baseline was lower in the MYL-1402O arm (0.6%) compared to the bevacizumab arm (2.5%).

Conclusions:

MYL-1402O is therapeutically equivalent to bevacizumab, based on the ORR analyses, with comparable secondary endpoints.

Trial Registry Information

EU Clinical Trials Register, Registration # EudraCT no. 2015-005141-32https://www.clinicaltrialsregister.eu/ctr-search/search?query=2015-005141-32

Plain language summary

Previous studies established bioequivalence of the proposed bevacizumab biosimilar MYL-1402O to reference bevacizumab. In this randomized, double-blind, phase III trial, MYL-1402O (n = 337) demonstrated comparable efficacy to bevacizumab (n = 334) in treating advanced non-squamous non-small-cell lung cancer per Food and Drug Administration and European Medicines Agency requirements for equivalence; the ratio of objective response rate (ORR) was 0.96 [90% confidence interval (CI) 0.83, 1.12] and the difference in ORR (MYL-1402O:bevacizumab) was −1.6 (95% CI −9.0, 5.9). Median progression-free survival at 42 weeks was comparable: 7.6 (7.0, 9.5) with MYL-1402O versus 9.0 (7.2, 9.7) months (p = 0.0906) with bevacizumab, by independent review. Treatment-emergent adverse events leading to death (2.4% vs 1.5%), serious adverse events (17.6% vs 16.7%), and antidrug antibodies (6.5% vs 4.8%), were comparable in the MYL-1402O vs bevacizumab arms, respectively. The incidence of neutralizing antibody post-baseline was lower with MYL-1402O (0.6%) than with bevacizumab (2.5%). These findings confirm therapeutic equivalence of MYL-1402O to bevacizumab, providing opportunities for improving access to bevacizumab.

The First WHO International Standard for Harmonizing the Biological Activity of Bevacizumab

Several Bevacizumab products are approved for clinical use, with many others in late-stage clinical development worldwide. To aid the harmonization of potency assessment across different Bevacizumab products, the first World Health Organization (WHO) International Standard (IS) for Bevacizumab has been developed. Two preparations of a Bevacizumab candidate and comparator were assessed for their ability to neutralize and bind vascular endothelial growth factor (VEGF) using different bioassays and binding assays in an international collaborative study. Relative potency estimates were similar across different assays for the comparator or the duplicate-coded candidate sample. Variability in relative potency estimates was reduced when the candidate standard was used for calculation compared with various in-house reference standards, enabling harmonization in bioactivity evaluations. The results demonstrated that the candidate standard is suitable to serve as an IS for Bevacizumab, with assigned unitages for VEGF neutralization and VEGF binding activity. This standard coded 18/210 was established by the WHO Expert Committee on Biological Standardization, which is intended to support the calibration of secondary standards for product development and lifecycle management. The availability of IS 18/210 will help facilitate the global harmonization of potency evaluation to ensure patient access to Bevacizumab products with consistent safety, quality and efficacy.

Real-world use of bevacizumab-awwb, a bevacizumab biosimilar, in US patients with metastatic colorectal cancer

Aim: Evaluated real world use of bevacizumab-awwb (MVASI^®), a bevacizumab biosimilar, for treating metastatic colorectal cancer (mCRC). Materials & methods: Adult mCRC patients who received bevacizumab-awwb during the first year after market availability were identified from the ConcertAI oncology dataset. Results: Of 304 patients, 47% initiated bevacizumab-awwb as reference product (RP) naive patients and 53% received bevacizumab-awwb with prior exposure to RP. Overall, 78% received bevacizumab-awwb as first-line therapy; the proportion was higher (91%) in RP-naive patients. Among RP-experienced patients, 83% were transitioned from RP to bevacizumab-awwb in the same line without disease progression; of those, the majority (83%) were transitioned within 28 days. Conclusion: Early evidence from US oncology practices suggests clinical adoption of bevacizumab-awwb in treating mCRC patients.

The Totality of Evidence and Use of ABP 215, a Biosimilar to Bevacizumab

ABP 215 (MVASI™, Amgen, Thousand Oaks, CA; MVASI™, Amgen Europe B.V., Netherlands) is a biosimilar to bevacizumab (Avastin^®, Genentech, South San Francisco, CA) reference product (RP), a monoclonal antibody targeting vascular endothelial growth factor A (VEGF-A). Here we provide a brief overview of the totality of evidence that supported the approval of ABP 215, along with practical considerations to ensure safe and effective administration.

ABP 215 has been shown to be highly similar to the RP, with similar mechanism of action, analytical (structural and functional) characteristics, binding, and potency. The similarity of PK parameters of ABP 215 and bevacizumab RP has been confirmed in healthy volunteers.

In a comparative clinical trial, patients with stage IV or recurrent non-squamous non-small cell lung cancer receiving carboplatin and paclitaxel were randomized to ABP 215 or bevacizumab RP. No clinically meaningful differences were found between ABP 215 and RP. The objective response rate (ORR) was 39% for ABP 215 and 41.7% for bevacizumab RP. The risk ratio for the ORR was 0.93 [90% confidence interval (CI), 0.80–1.09], which fell within the prespecified margin for equivalence of 0.67–1.5, indicating similar clinical efficacy.

Similar to bevacizumab RP, ABP 215 is supplied as a clear to slightly opalescent, colorless to pale yellow, sterile solution in a glass vial. It should be diluted in 0.9% sodium chloride in polyvinylchloride or polyolefin bags before administering as an intravenous infusion. The ABP 215 solution should be stored at 2–8 °C (36–46°F) prior to use. Physicochemical stability studies showed that there were no meaningful changes in purity or potency and no loss of protein after storage at 2–8 °C for 35 days followed by storage at 30 °C for 48 h.

Clinical and Regulatory Considerations for the Use of Bevacizumab Biosimilars in Metastatic Colorectal Cancer

Biosimilars - biological medicines highly similar to a licensed reference product (RP) - can mitigate the risk of drug shortages by providing treatment alternatives and, with their lower costs, increase patient access to medication and reduce health care expenditure. However, limited knowledge of biosimilar approval processes and lack of confidence in their quality and efficacy can limit their uptake. Importantly, biosimilars are approved based on tightly controlled regulatory pathways to demonstrate that the physical, chemical, and biological properties of the proposed biosimilar are highly similar to the RP, with no clinically meaningful differences. Initially, a battery of highly sensitive in vitro studies are performed, comparing critical quality attributes between the proposed biosimilar and RP. Subsequently, in vivo pharmacodynamic studies compare the activity and physiologic effects of the biosimilar and RP. Finally, clinical studies are conducted, including a pharmacokinetic equivalence study and a confirmatory comparative clinical trial. The latter is performed in the most sensitive patient population for which the RP is licensed, to provide the greatest possibility of identifying any clinically meaningful differences between the proposed biosimilar and RP. When equivalent safety and efficacy have been demonstrated in one setting, the totality of evidence, together with scientific justification that there are no anticipated differences between the RP and proposed biosimilar in mechanism of action, pharmacokinetics, immunogenicity or toxicity, allows extrapolation into indications where clinical studies were not performed with the proposed biosimilar. Here, we review the approval process for biosimilars, focusing on the licensing of bevacizumab biosimilars and their extrapolation to metastatic colorectal cancer.