Progression-Free Survival in Patients Receiving Chemotherapy Alone (C) or Chemotherapy with Bevacizumab (CB) for First-Line Treatment of KRAS Mutant Metastatic Colorectal Cancer in Community Oncology Settings

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.

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.

Comparative Effectiveness and Safety of Monoclonal Antibodies (Bevacizumab, Cetuximab, and Panitumumab) in Combination with Chemotherapy for Metastatic Colorectal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

The last decade has seen the increasing use of biological medicines in combination with chemotherapy containing 5-fluorouracil/oxaliplatin or irinotecan for the treatment of metastatic colorectal cancer (mCRC). These combinations have resulted in increased progression-free survival (PFS) in patients with mCRC; however, there are remaining concerns over the extent of their effect on overall survival (OS). Published studies to date suggest no major differences between the three currently available monoclonal antibodies (MoAbs); however, there are differences in costs. In addition, there is rising litigation in Brazil in order to access these medicines as they are currently not reimbursed.

OBJECTIVE

The aim was to investigate the comparative effectiveness and safety of three MoAbs (bevacizumab, cetuximab and panitumumab) associated with fluoropyrimidine-based chemotherapy regimens and compared to fluoropyrimidine-based chemotherapy alone in patients with mCRC, through an updated systematic review and meta-analysis of concurrent or non-concurrent observational cohort studies, to guide authorities and the judiciary.

METHOD

A systematic review and meta-analysis was performed based on cohort studies published in databases up to November 2017. Effectiveness measures included OS, PFS, post-progression survival (PPS), Response Evaluation Criteria In Solid Tumors (RECIST), response rate, metastasectomy and safety. The methodological quality of the studies was also evaluated.

RESULTS

A total of 21 observational cohort studies were included. There were statistically significant and clinically relevant benefits in patients treated with bevacizumab versus no bevacizumab mainly around OS, PFS, PPS and the metastasectomy rate, but not for the disease control rates. However, there was an increase in treatment-related toxicities and concerns with the heterogeneity of the studies.

CONCLUSION

The results pointed to an advantage in favor of bevacizumab for OS, PFS, PPS, and metastasectomy. Although this advantage may be considered clinically modest, bevacizumab represents a hope for increased survival and a chance of metastasectomy for patients with mCRC. However, there are serious adverse events associated with its use, especially severe hypertension and gastrointestinal perforation, that need to be considered.

Difference between right-sided and left-sided colorectal cancers: from embryology to molecular subtype

INTRODUCTION

Colorectal cancer is one of the most common malignancies in the world, and it exhibits differences in incidence, pathogenesis, molecular pathways, and outcome depending on the location of the tumor. Differences in the microbiome, clinical characteristics, and chromosomal and molecular characteristics have been reported between the right and left side of the colon. Areas covered: This review focuses on the latest developments in epidemiological and chromosomal and molecular studies, which have enhanced our understanding on the underlying genetic and immunological differences between the right-sided colon and the left-sided colorectum in metastatic colorectal cancer. Expert commentary: The numerous findings regarding differences between right- and left-sided colon cancers should have an impact on colorectal cancer screening and therapy. The location of the colorectal cancer should be considered before group stratification into genetic, clinical, and especially chemotherapy trials. A more tailored approach to colon cancer treatment would be highly desirable if future trials further support the hypothesis of two distinct tumor entities.