A randomized, double-blind, phase III, non-inferiority clinical trial comparing the efficacy and safety of TA4415V (a proposed Trastuzumab biosimilar) and Herceptin (Trastuzumab reference product) in HER2-positive early-stage breast Cancer patients

Biosimilars: A Critical Review of Development, Regulatory Landscape, and Clinical Implications

The biopharmaceutical industry has witnessed significant growth in the development and approval of biosimilars. These biosimilars aim to provide cost-effective alternatives to expensive originator biosimilars, alleviating financial pressures within healthcare. The manufacturing of biosimilars is a highly complex process that involves several stages, each of which must meet strict regulatory standards to ensure that the final product is highly similar to the reference biologic. To gain regulatory approval, biosimilars must undergo rigorous analytical characterization including in vitro assays, bioanalytical evaluations, and clinical similarity studies like pharmacokinetic (PK), pharmacodynamic (PD) assessments-to demonstrate safety, efficacy, quality comparability with reference products. Leading regulatory agencies such as the European Medicines Agency (EMA), the World Health Organization (WHO), and the United States Food and Drug Administration (US FDA) have established stringent guidelines for biosimilar evaluation and post-marketing surveillance. Despite this regulatory clarity, challenges around interchangeability, market exclusivity, and patent protection often delay market access and limit adoption, particularly in regions where automatic substitution is restricted. Case studies of biosimilars such as rituximab, adalimumab, filgrastim, and trastuzab reveal both advancements and ongoing hurdles in achieving broader market integration. The introduction of biosimilars has shown potential to reduce healthcare costs; for example, a recent analysis indicates a 20-30% cost reduction in the U.S. due to biosimilar adoption. As the biosimilar market expands, collaborative efforts among regulatory bodies, industry stakeholders, and healthcare providers are essential to enhance access to biologic therapies. This collaboration is poised to improve patient outcomes and catalyse transformative change in global healthcare systems.

Mechanisms underlying dose-limiting toxicities of conventional chemotherapeutic agents

Dose-limiting toxicities (DLTs) are severe adverse effects that define the maximum tolerated dose of a cancer drug. In addition to the specific mechanisms of each drug, common contributing factors include inflammation, apoptosis, ion imbalances, and tissue-specific enzyme deficiencies. Among various DLTs are bleomycin-induced pulmonary fibrosis, doxorubicin-induced cardiomyopathy, cisplatin-induced nephrotoxicity, methotrexate-induced hepatotoxicity, vincristine-induced neurotoxicity, paclitaxel-induced peripheral neuropathy, and irinotecan, which elicits severe diarrhea. Currently, specific treatments beyond dose reduction are lacking for most toxicities. Further research on cellular and molecular pathways is imperative to improve their management. This review synthesizes preclinical and clinical data on the pharmacological mechanisms underlying DLTs and explores possible treatment approaches. A comprehensive perspective reveals knowledge gaps and emphasizes the need for future studies to develop more targeted strategies for mitigating these dose-dependent adverse effects. This could allow the safer administration of fully efficacious doses to maximize patient survival.

Biosimilar monoclonal antibodies for cancer treatment in adults

BACKGROUND

Biosimilars are products containing an approved biological medicine. They are similar, but not identical, to an originator medicine. In cancer, biosimilars have been developed from the monoclonal antibodies, bevacizumab, rituximab, and trastuzumab. They have become available for the treatment of lung, colorectal, non-Hodkin's lymphoma, and breast cancers. As these biological products are not identical, synthesis of evidence of the clinical effects of biosimilars compared to their originators is needed to understand their comparative effectiveness and harms.

OBJECTIVES

To evaluate the benefits and harms of biosimilar monoclonal antibodies versus their originator drugs for adults with cancer.

SEARCH METHODS

We searched bibliographic (CENTRAL, MEDLINE, Embase, Web of Science) and clinical trials databases to February 2024.

SELECTION CRITERIA

We included head-to-head randomised controlled trials conducted in adults with cancer treated with biosimilar or originator monoclonal antibodies.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methodology. Primary outcomes were progression-free survival, duration of response, overall survival, breast cancer's pathological complete response, serious adverse events, and health-related quality of life. If survival estimates were adjusted or provided as rates, we did not combine them. We used Cochrane's RoB 1 tool to assess the risk of bias and GRADE to evaluate the certainty of evidence of critical and important outcomes according to the relevance determined by consumers.

MAIN RESULTS

We included 55 studies with 22,046 adults (23 of bevacizumab, 10,639 participants with colorectal or lung cancer; 17 of rituximab, 4412 participants with non-Hodgkin's lymphoma; and 15 of trastuzumab, 6995 participants with breast cancer). Studies were conducted in all continents, most were multicentre, and all were funded by the drug manufacturer. Participants' ages ranged from 47 (mean) to 62 (median) years and the proportion of women from 18% to 100%. Fifteen studies were conducted as non-inferiority and 40 as equivalence. The overall risk of bias was low; main biases were in the incomplete outcome data and selective reporting domains. Bevacizumab biosimilar versus bevacizumab originator in lung or colorectal cancer Progression-free survival is likely similar between bevacizumab biosimilar and the originator (per 1000: 380 in both groups at 12 months, hazard ratio (HR) 1.00, 95% confidence interval (CI) 0.91 to 1.09; 5 studies, 2660 participants; moderate-certainty evidence). There were no differences in lung or colorectal cancer subgroups. Bevacizumab biosimilar is likely similar to the originator in duration of response (per 1000: 219 participants who achieved response progressed with biosimilar versus 210 with originator at 12 months; HR 1.05, 95% CI 0.81 to 1.37; 1 study, 762 participants; moderate-certainty evidence) and overall survival (per 1000: 592 with biosimilar versus 610 with originator at 12 months; HR 1.06, 95% CI 0.94 to 1.19; 5 studies, 2783 participants; moderate-certainty evidence). There were no differences in cancer type subgroups. Bevacizumab biosimilar is likely similar to the originator in serious adverse events (per 1000: 303 with biosimilar versus 309 with originator; risk ratio (RR) 0.98, 95% CI 0.93 to 1.03; 23 studies, 10,619 participants; moderate-certainty evidence). Bevacizumab biosimilar may be similar to originator in health-related quality of life as scores were comparable in the one study that assessed this outcome in metastatic colorectal cancer (low-certainty evidence). This critical outcome was not assessed in other biosimilars comparisons. Bevacizumab biosimilar is likely similar to originator in objective response (per 1000: 481 with biosimilar versus 501 with originator; RR 0.96, 95% CI 0.93 to 1.00; 23 studies, 10,054 participants; moderate-certainty evidence) and mortality (per 1000: 287 with biosimilar versus 279 with originator; RR 1.03, 95% CI 0.97 to 1.09; 19 studies, 9231 participants; moderate-certainty evidence). There were no differences in lung or colorectal cancers. Rituximab biosimilar versus rituximab originator in non-Hodgkin's lymphoma Rituximab biosimilar is likely similar to originator in progression-free survival (7 studies, 2456 participants), duration of response (2 studies, 522 participants), and overall survival (7 studies, 2353 participants; data not pooled as survival estimates were adjusted for different factors or reported as rates) (all moderate-certainty evidence). Rituximab biosimilar is likely similar to originator in the risk of serious adverse events (per 1000: 210 with biosimilar versus 204 with originator; RR 1.03, 95% CI 0.94 to 1.14; 15 studies, 4197 participants; moderate-certainty evidence) and objective response (per 1000: 807 with biosimilar versus 799 with originator; RR 1.01, 95% CI 0.98 to 1.04; 16 studies, 3922 participants; moderate-certainty evidence). No study reported quality of life. Rituximab biosimilar is similar to originator in mortality (per 1000: 52 with biosimilar versus 53 with originator; RR 0.97, 95% CI 0.70 to 1.35; 8 studies, 2557 participants; high-certainty evidence). Trastuzumab biosimilar versus trastuzumab originator in breast cancer Trastuzumab biosimilar is likely similar to originator in progression-free survival (4 studies, 2221 participants), duration of response (3 studies, 1488 participants), and overall survival (6 studies, 2221 participants), which were not pooled due to adjustment for different factors or provided as rates. No study reported quality of life. Trastuzumab biosimilar may be similar to originator in pathological complete response (per 1000: 459 with biosimilar versus 433 with originator; RR 1.06, 95% CI 0.95 to 1.17; 7 studies, 3403 participants; low-certainty evidence), is likely similar in serious adverse events (per 1000: 129 in both groups; RR 1.00, 95% CI 0.85 to 1.17; 13 studies, 6183 participants; moderate-certainty evidence), and slightly increases objective response (per 1000: 801 with biosimilar versus 777 with originator; RR 1.03, 95% CI 1.01 to 1.05; 13 studies, 5509 participants; moderate-certainty evidence).

AUTHORS' CONCLUSIONS

Treatment with bevacizumab, rituximab, and trastuzumab biosimilars are likely similar to their originator drugs in terms of their impact on progression-free survival, duration of response, overall survival, serious adverse events, objective response, and mortality. Limited evidence showed similarity in pathological complete response for trastuzumab and quality of life for bevacizumab compared with originators, which was not assessed in the other comparisons. The overall certainty of evidence was moderate and imprecision was the main reason for downgrading our certainty in the findings.

Safety evaluation of the trastuzumab biosimilar in Iranian women with HER2-positive breast cancer undergoing adjuvant chemotherapy: a post-marketing surveillance

BACKGROUND

Trastuzumab is a humanized monoclonal antibody against the human epidermal growth factor receptor 2 (HER2). This post-marketing surveillance evaluates the safety of a trastuzumab biosimilar (AryoTrust), produced by AryoGen Co. Iran in Iranian women with HER2-positive non-metastatic breast cancer (BC).

RESEARCH DESIGN AND METHODS

The patients who had undergone adjuvant chemotherapy regimens received trastuzumab every 3 weeks for nine cycles. The study started in February 2017 and finished in August 2022. Data regarding safety were collected using booklets and then analyzed.

RESULTS

A total of 597 women with a mean ±SD age of 48.13 ± 10.18 years underwent 5,313 injection cycles. They received pre-study chemotherapies consisting of anthracyclines, taxanes, both, or other medications in 6.70, 7.20, 82.41, and 2.01% of the cases, respectively. One hundred and thirty-nine patients experienced at least one adverse event (AE). The most common AEs were decreased ejection fraction (EF, 5.7%), peripheral neuropathy (5.36%), and nausea (5.19%). Meningioma was the only life-threatening serious AE. Furthermore, bone pain and infusion-related reactions were the two most common grade three AEs. Nevertheless, the mean EF of patients did not change notably during the study.

CONCLUSIONS

The results demonstrate that this trastuzumab biosimilar is a generally well tolerated and safe treatment for HER2-positive BC.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT06021379.

Monoclonal antibody biosimilars for cancer treatment

Monoclonal antibodies are important cancer medicines. The European Medicines Agency (EMA) approved 48 and the Food and Drug Administration (FDA) 56 anticancer monoclonal antibody-based therapies. Their high prices burden healthcare systems and hamper global drug access. Biosimilars could retain costs and expand the availability of monoclonal antibodies. In Europe, five rituximab biosimilars, six trastuzumab biosimilars, and eight bevacizumab biosimilars are available as anti-cancer drugs. To gain insight into the biosimilar landscape for cancer treatment, we performed a literature search and analysis. In this review, we summarize cancer monoclonal antibodies' properties crucial for the desired pharmacology and point out sources of variability. The analytical assessment of all EMA-approved bevacizumab biosimilars is highlighted to illustrate this variability. The global landscape of investigational and approved biosimilars is mapped, and the challenges for access to cancer biosimilars are identified.

Clinical Benefit, Price, and Uptake for Cancer Biosimilars vs Reference Drugs in China: A Systematic Review and Meta-Analysis

Importance

The high cost of biologics used to treat cancer has been an increasing burden in the world. In China, the recent approval of cancer biosimilar drugs to resolve this problem is promising, but evidence of clinical benefits, price, and uptake for these drugs is still lacking.

Objectives

To compare characteristics of pivotal clinical trials in China and other countries for biosimilars of bevacizumab, rituximab, and trastuzumab and investigate the efficacy or effectiveness, safety, and immunogenicity outcomes of cancer biosimilars compared with reference drugs by meta-analysis.

Data Sources

For this systematic review and meta-analysis, PubMed, Embase, the Cochrane Library, and ClinicalTrials.gov were searched for published studies from database inception to February 1, 2023, using the search topics (cancers) AND (biosimilars).

Study Selection

Randomized clinical trials and cohort studies that included patients with cancer were included.

Data Extraction and Synthesis

Two authors independently extracted the outcome estimates and characteristics for each study. A random-effects meta-analysis was performed to summarize the relative estimates with 95% CIs. This study was performed following the Preferred Reporting Items for Systematic Reviews and Meta-analyses guideline.

Main Outcomes and Measures

Clinical trial characteristics were collected for biosimilars of bevacizumab, rituximab, and trastuzumab. The relative estimates of efficacy or effectiveness (objective response rate, progression-free survival, and overall survival), safety, and immunogenicity outcomes were analyzed for biosimilars vs reference drugs. The weighted average price and uptake rate were evaluated for biosimilars relative to their reference drugs between 2015 and 2022.

Results

A total of 39 RCTs (involving 18 791 patients) and 10 cohort studies (involving 1998 patients) were included. The biosimilars of bevacizumab (16 RCTs; risk ratio [RR], 0.97; 95% CI, 0.93-1.01; P = .17), rituximab (12 RCTs; RR, 1.03; 95% CI, 0.98-1.08; P = .70), and trastuzumab (9 RCTs: RR, 1.04; 95% CI, 0.97-1.12; P = .29) met equivalence with reference biologics in regard to the objective response rate. The results summarized from cohort studies were consistent with those from RCTs. In 2022, cancer biosimilars were priced at 69% to 90% of the costs for the reference drugs, and their uptake reached 54% to 83% in China.

Conclusions and Relevance

This systematic review and meta-analysis indicated that cancer biosimilars provided comparable clinical benefits at lower prices compared with reference drugs. These findings suggest the potential feasibility of expediting the transition from reference drugs to biosimilars to benefit more patients with cancer.

Landscape of neoadjuvant therapy in HER2-positive breast cancer: a systematic review and network meta-analysis

BACKGROUND

The recommended preoperative approach for HER2-positive breast cancer is unclear. We aimed to investigate the following: i) what is the optimal neoadjuvant regimen and ii) whether anthracyclines could be excluded.

METHODS

A systematic literature search in Medline, Embase and Web of Science databases was performed. Studies had to satisfy the following criteria: i) randomised controlled trials (RCTs), ii) enroled patients treated preoperatively for HER2-positive BC (breast cancer), iii) at least one treatment group received an anti-HER2 agent, iv) available information of any efficacy end-point and v) published in English. A network meta-analysis with a frequentist framework using random-effects model was used to pool direct and indirect evidence. Pathologic complete response (pCR), event-free survival (EFS) and overall survival (OS) were the efficacy end-points of interest, and selected safety end-points were also analysed.

RESULTS

A total of 11,049 patients with HER2-positive BC (46 RCTs) were included in the network meta-analysis, and 32 different regimens were evaluated. Dual anti-HER2-therapy, with pertuzumab or tyrosine kinase inhibitors, combined with chemotherapy was significantly superior to trastuzumab and chemotherapy in terms of pCR, EFS and OS. However, a higher risk of cardiotoxicity was observed with dual anti-HER2-therapy. Anthracycline-based chemotherapy was not associated with better efficacy outcomes in comparison with non-anthracycline-based chemotherapy. In anthracycline-free regimens, the addition of carboplatin presented numerically better efficacy outcomes.

CONCLUSION

Dual HER2 blockade with chemotherapy is the recommended choice as neoadjuvant therapy for HER2-positive breast cancer, preferably by omitting anthracyclines in favour of carboplatin.