Real-world intensive safety monitoring of biosimilars rituximab and trastuzumab in a Portuguese oncology hospital

Safety of marketed biosimilar monoclonal antibody cancer treatments in the US: a disproportionality analysis using the food and drug administration adverse event reporting system (FAERS) database

BACKGROUND

By 31 December 2022, the United States Food and Drug Administration (FDA) has approved 12 biosimilar monoclonal antibody cancer treatments. This study detected disproportionate adverse event (AE) reporting signals and compared safety profile of individual biosimilars to their originator biologics and between each pair of biosimilars.

RESEARCH DESIGN AND METHODS

The FDA Adverse Event Reporting System data (6/1/2018-12/31/2022) were used to identify AE reports for rituximab, bevacizumab, trastuzumab, and their marketed biosimilars. Reporting odds ratios and empirical Bayesian geometric mean were computed to detect reporting disproportionality in serious, death, and specific AEs between studied biologics/biosimilars and all other drugs.

RESULTS

Significant AE reporting signals were identified: 1) death for biological rituximab, pruritus for biosimilar rituximab-pvvr, and infusion-related reactions for biological rituximab and biosimilar rituximab-pvvr (significantly higher ROR for rituximab-pvvr than biological rituximab, p < .0001); 2) death for biological bevacizumab and biosimilar bevacizumab-bvzr (significantly higher ROR for bevacizumab-bvzr than biological bevacizumab, p < .0001), hypertension, platelet count decreased (PCD), and proteinuria for biological bevacizumab and biosimilar bevacizumab-awwb (significantly higher ROR of PCD for bevacizumab-awwb than originator bevacizumab, p = .001); and 3) rash for biosimilar trastuzumab-anns.

CONCLUSIONS

Findings call for large, longitudinal studies to examine causality of certain AEs with rituximab-pvvr and bevacizumab biosimilars.

Efficacy and safety of biosimilar trastuzumab (CT-P6) in routine clinical practice in the Republic of Korea: a real-world post-marketing surveillance study

BACKGROUND

The trastuzumab biosimilar CT-P6 is approved for human epidermal growth factor receptor 2 (HER2)-positive early breast cancer (EBC), metastatic breast cancer (MBC), and metastatic gastric cancer (MGC). The objective of this post-marketing surveillance (PMS) study was to evaluate the real-world safety and effectiveness of CT-P6 in patients with HER2-positive cancers.

RESEARCH DESIGN AND METHODS

This open-label, observational, prospective, PMS study collected data via investigator surveys from 35 centers in the Republic of Korea (5 October 2018-4 October 2022). Eligible patients with HER2-positive EBC, MBC, or MGC started CT-P6 treatment during routine clinical practice, followed by 1-year observation. Evaluations included adverse events (AEs), adverse drug reactions (ADRs), and effectiveness.

RESULTS

Safety was analyzed in 642 patients (494 EBC, 94 MBC, 54 MGC). Overall, 325 (50.6%) patients experienced 1316 AEs, and 550 ADRs occurred in 199 (31.0%) patients. Unexpected ADRs occurred in 62 (9.7%) patients. Unexpected ADRs and ADRs of special interest did not raise any new safety signals. Among trastuzumab-naïve patients, 34/106 (32.1%) with EBC achieved pathological complete response; 30/74 (40.5%) MBC and 24/49 (49.0%) MGC patients achieved complete or partial response.

CONCLUSIONS

In a real-world setting, CT-P6 demonstrated safety and efficacy findings consistent with previous CT-P6 studies.

A non-interventional, post-marketing surveillance study evaluating the safety and effectiveness of biosimilar rituximab (CT-P10) during routine clinical practice in the Republic of Korea

BACKGROUND

CT-P10 was the first licensed rituximab biosimilar. This Korean post-marketing surveillance study evaluated CT-P10 safety and effectiveness in approved indications.

RESEARCH DESIGN AND METHODS

This prospective, open-label, observational, phase 4 study collected routine clinical practice data across 27 centers in the Republic of Korea. Patients received their first CT-P10 treatment, per prescribing information, for non-Hodgkin's lymphoma (NHL), chronic lymphocytic leukemia (CLL), rheumatoid arthritis (RA), granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA) during the surveillance period (16 November 2016-15 November 2020). Safety (including adverse events [AEs] and adverse drug reactions [ADRs]) and disease-specific clinical response (by best overall response [NHL/CLL], Disease Activity Score in 28-joints [RA], or Birmingham Vasculitis Activity Score for Wegener's Granulomatosis [GPA/MPA]) were assessed for ≤1 year (NHL/CLL) or ≤24 weeks (RA/GPA/MPA).

RESULTS

The safety population comprised 677 patients (604 NHL, 16 CLL, 42 RA, 7 GPA, 8 MPA). AEs/ADRs were reported for 68.4%/27.7% (NHL/CLL), 31.0%/14.3% (RA), and 86.7%/13.3% (GPA/MPA) of patients. Serious AEs and unexpected ADRs did not raise new safety signals. Pneumonia was the most frequent serious ADR overall. Positive effectiveness outcomes were observed.

CONCLUSIONS

Findings were consistent with the known CT-P10/reference rituximab safety profile, with high effectiveness observed in NHL/CLL and RA.

Adverse event reporting of marketed biosimilar and biological monoclonal antibody cancer treatments in the United States

BACKGROUND

By 8 September 2022, 10 biological monoclonal antibody (mAb) biosimilar products for cancer treatment had been approved and marketed in the United States (US). This study examined adverse event (AE) reporting patterns and disproportionate reporting signals for mAb biosimilars in the US compared to their originator biologics.

RESEARCH DESIGN AND METHODS

The US Food and Drug Adverse Event Reporting System database was used to identify AE reports for biological rituximab, bevacizumab, trastuzumab, and their marketed biosimilars. Proportions of patient age, sex and type of reporters of AEs were described for these reports. Reporting odds ratios (RORs) with 95% confidence intervals were calculated to compare reporting disproportionality in serious, death, and specific AEs between mAb biologics/biosimilars (index) and all other drugs. Breslow-Day statistic was used to determine homogeneity in RORs between each mAb biologic-biosimilar pair at p < 0.05.

RESULTS

We observed no risk signals of serious or death AE reporting for all three mAb biosimilars. A signal of disproportionate reporting of death was detected between biological and biosimilar bevacizumab (p < 0.05).

CONCLUSIONS

Our findings support the similarity in signals of disproportionate AE reporting between mAb originator biologics and biosimilars, except for death between biological and biosimilar bevacizumab.

A Developer's Perspective on Clinical Evidence and Benefits for Rituximab Biosimilar Uptake, with a Focus on CT-P10

To date, four rituximab biosimilars have received regulatory approval from the European Medicines Agency and/or US Food and Drug Administration. CT-P10 was the first rituximab biosimilar to be approved by each agency, in 2017 and 2018, respectively. Regulatory approval of CT-P10 followed demonstration of pharmacokinetic equivalence to the reference product in a phase I study in patients with rheumatoid arthritis. Phase III pivotal studies of CT-P10 subsequently demonstrated equivalence or non-inferiority of pharmacokinetics and efficacy between CT-P10 and reference rituximab in patients with rheumatoid arthritis, advanced-stage follicular lymphoma, and low-tumour-burden follicular lymphoma. Almost 5 years after its initial regulatory approval, significant real-world experience has accumulated with CT-P10 use, particularly in diffuse large B-cell lymphoma, one of the indications approved by extrapolation. This article summarises the pivotal data underlying regulatory approval for the four licensed rituximab biosimilars, before focusing on real-world data gathered with CT-P10. These data provide further support for the safety and effectiveness of CT-P10 and should boost healthcare professional and patient confidence in its use. Pharmacoeconomic analyses support the potential healthcare system cost savings offered by rituximab biosimilar uptake, which could lead to improved patient access to biologic treatments. Opportunities arising from biosimilar uptake extend further, potentially enabling innovative investigator-led research and therapeutic advances.

Uptake of Trastuzumab Biosimilars for the Treatment of HER2-Positive Breast Cancer: A Real-World Experience from a Cancer Center

Background: The introduction of trastuzumab biosimilars in clinical practice plays an important role in promoting the sustainability of healthcare systems. By contrast, the switching process can be challenging to the clinics. This survey describes the switching process at a National Cancer Institute over a period of 2 years. Methods: Data regarding all trastuzumab-based regimens for breast cancer (BC) from 1 January 2019 and 31 December 2020 were extracted from both adverse drug reactions (ADRs) reporting systems and electronic systems involved in inventory management, prescribing, dispensing, and administration. Both patients under monotherapy and combination treatment regimens were included. There were no exclusion criteria. Results and Conclusions: Overall 354 patients received at least one trastuzumab-based regimen for a total of 493 lines of treatment and 5769 administrations. Biosimilar were used in 34.3% of trastuzumab-based treatments. No differences between biosimilars and reference drug have been observed in terms of ADRs. The effective cost-saving of the first 2 years is greater than EUR 800,000 and it is estimated to increase over time.