A phase I, randomized, single-dose study evaluating the pharmacokinetic equivalence of biosimilar ABP 215 and bevacizumab in healthy adult men

Survey of Data Package and Sample Size of Comparative Clinical Studies for Biosimilar Developments from PMDA Assessments

BACKGROUND

The Japanese biosimilar guideline requires that the sponsors conduct clinical studies such as comparative pharmacokinetic (PK), pharmacodynamic (PD), or efficacy studies. In each biosimilar development, the sponsors consider the clinical data package, and thus clinical data packages vary among biosimilar developments.

OBJECTIVES

The aim of this study was to elucidate the clinical data packages for the biosimilars approved in Japan. The details of clinical data packages and sample size for the regulatory approvals of biosimilars in Japan was reported.

METHODS

We surveyed the clinical data packages and sample size based on the Pharmaceuticals and Medical Devices Agency (PMDA) website review reports between 2009 and 2023.

RESULTS

Twenty-four biosimilars have been approved based on the comparative PK and efficacy studies, 10 biosimilars have been approved based on the comparative PK/PD study, and one biosimilar has been approved based on the comparative efficacy study. Regarding the sample size, comparative PK studies were conducted in healthy volunteers or patients for up to 300 cases, although the majority enrolled only 1-100 cases (68.1%, 32/47). Comparative PD studies enrolling 1-30, 31-60, and 61-90 cases totaled 4, 7, and 4 cases, respectively. Finally, comparative efficacy studies enrolling 1-300, 301-600, and 601-900 totaled 6, 10, and 11 cases, respectively. In particular, the oncology and rheumatology areas were the first and second disease areas recruiting 601-900 patients.

CONCLUSION

Large numbers of patients were enrolled to conduct a comparative efficacy study. Efficient biosimilar development should be considered on the basis of the accumulation of scientific understanding of comparable features of biosimilars and their development.

Real-World Safety and Effectiveness of a Bevacizumab Biosimilar (ABP 215) in Metastatic Colorectal Cancer Patients in Canada

BACKGROUND

ABP 215 is a biosimilar to the reference product, bevacizumab, and was one of the first biosimilars approved by Health Canada for the first-line treatment of metastatic colorectal cancer (mCRC). This study aimed to address gaps in real-world evidence (RWE) including patient characteristics, treatment safety (primary objective), and effectiveness (secondary objective) for first-line ABP 215 therapy in Canadian patients with mCRC.

MATERIALS AND METHODS

Retrospective data were collected in 2 waves, at least 1 year (Wave 1) or 2 years (Wave 2) after commercial availability of ABP 215 at each participating site.

RESULTS

A total of 75 patients from Wave 1 and 164 patients from Wave 2 treated with a minimum of 1 cycle of ABP 215 were included. At least one safety event of interest (EOI) was recorded for 34.7% of Wave 1 and 42.7% of Wave 2 patients. The median progression free survival (PFS) for Wave 1 and 2 patients were 9.47 (95% confidence interval [CI]: 6.71, 11.90) and 21.38 (95% CI: 15.82, not estimable) months, respectively. Median overall survival was not estimable for Wave 1 and was 26.45 months for Wave 2.

CONCLUSION

The safety and effectiveness of ABP 215 observed in this real-world study were comparable to clinical trial findings and to other RWE with longer PFS in the current study.

Pooled analysis of three pharmacokinetic studies comparing biosimilar MB02 and reference bevacizumab

AIM

The aim of this study was to add robustness and provide further evidence on the bioequivalence, safety and immunogenicity between MB02 and reference bevacizumab. No similar study has been performed before with a biosimilar monoclonal antibody.

METHODS

Population analysis by pooling data from three independent pharmacokinetic (PK) studies was performed. The studies had a single-dose, double-blind, three-arm, parallel-group design and two studies, MB02-A-02-17 and MB02-A-05-18, compared MB02 to EU- and US-bevacizumab in Caucasian subjects, while study MB02-A-04-18 compared MB02 and EU-bevacizumab in Japanese participants. Primary endpoints included maximum observed serum concentration (Cmax ), area under the serum concentration-time curve (AUC) from time zero and extrapolated to infinity (AUC0-∞ ) and AUC from time zero to the time of last quantifiable concentration (AUC0-t ). Secondary endpoints included other PK parameters, safety and immunogenicity. A sensitivity analysis using actual protein concentration as a correction factor was applied to primary PK parameters.

RESULTS

Point estimates and 90% confidence intervals for the geometric mean ratios of primary PK parameters for MB02, EU- and US-bevacizumab were all contained within the predefined bioequivalence margins (80%-125%) for all pairwise comparisons. The same results for all pairwise comparisons were observed when protein-corrected primary PK parameters were analyzed. Safety and immunogenicity were similar between MB02 and the EU- and US-reference bevacizumab in healthy subjects.

CONCLUSIONS

This pooled analysis of three comparable PK studies further supports the bioequivalence of biosimilar MB02 to EU- and US-reference bevacizumab. No clinically meaningful differences in safety or immunogenicity were observed.

Translational physiologically-based pharmacokinetic model for ocular disposition of monoclonal antibodies

We have previously published a PBPK model comprising the ocular compartment to characterize the disposition of monoclonal antibodies (mAbs) in rabbits. While rabbits are commonly used preclinical species in ocular research, non-human primates (NHPs) have the most phylogenetic resemblance to humans including the presence of macula in the eyes as well as higher sequence homology. However, their use in ocular research is limited due to the strict ethical guidelines. Similarly, in humans the ocular samples cannot be collected except for the tapping of aqueous humor (AH). Therefore, we have translated this rabbit model to monkeys and human species using literature-reported datasets. Parameters describing the tissue volumes, physiological flows, and FcRn-binding were obtained from the literature, or estimated by fitting the model to the data. In the monkey model, the values for the rate of lysosomal degradation for antibodies (Kdeg), intraocular reflection coefficients (σaq, σret, σcho), bidirectional rate of fluid circulation between the vitreous chamber and the aqueous chamber (QVA), and permeability-surface area product of lens (PSlens) were estimated; and were found to be 31.5 h-1, 0.7629, 0.6982, 0.9999, 1.64 × 10-5 L/h, and 4.62 × 10-7 L/h, respectively. The monkey model could capture the data in plasma, aqueous humor, vitreous humor and retina reasonably well with the predictions being within twofold of the observed values. For the human model, only the value of Kdeg was estimated to fit the model to the plasma pharmacokinetics (PK) of mAbs and was found to be 24.4 h-1 (4.14%). The human model could also capture the ocular PK data reasonably well with the predictions being within two- to threefold of observed values for the plasma, aqueous and vitreous humor. Thus, the proposed framework can be used to characterize and predict the PK of mAbs in the eye of monkey and human species following systemic and intravitreal administration. The model can also facilitate the development of new antibody-based therapeutics for the treatment of ocular diseases as well as predict ocular toxicities of such molecules following systemic administration.

A Randomized, Double-Blind, Parallel-Controlled Phase I Study Comparing the Pharmacokinetics, Safety, and Immunogenicity of SCT510 to Bevacizumab (Avastin®) in Healthy Chinese Males

BACKGROUND

SCT510 is a recombinant humanized monoclonal antibody targeting vascular endothelial growth factor (VEGF), which is intended as a candidate biosimilar of bevacizumab that is approved for various metastatic cancers.Please confirm change in wording to match definition for VEGF belowYes.

OBJECTIVE

This study aimed to compare the pharmacokinetics profiles, safety, and immunogenicity of SCT510 to bevacizumab (Avastin^®) in healthy Chinese males.

METHODS

This was a single-center, double-blind, parallel-group phase I study. A total of 84 participants were randomly assigned (1:1) to receive a single 3 mg/kg infusion of either SCT510 or bevacizumab and followed up for 99 days. Primary endpoints were area under the serum concentration-time curve from time 0 extrapolated to infinity (AUC_0-∞), area under the serum concentration-time curve from time 0 to last quantifiable concentration (AUC_0-t), and the maximum observed concentration (C_max). Secondary endpoints included safety and immunogenicity.Kindly check and confirm the edit made in the article title.Yes.

RESULTS

A total of 82 subjects completed the study. Geometric means ratios (GMR) for AUC_0-∞, AUC_0-t, and C_max were 0.88, 0.89, and 0.97, respectively, for SCT510 versus bevacizumab (USA). The 90% confidence intervals for GMRs of AUC_0-∞, AUC_0-t, and C_max were all within the prespecified criteria (80-125%). No adverse events (AEs) led to study termination, and no serious adverse events (SAEs) were reported. None of the anti-drug antibodies (ADAs) identified were found to be neutralizing antibodies (NAbs), and only one subject from the SCT510 group tested positive for the ADA at the day 99 visit.

CONCLUSION

This study demonstrated that the pharmacokinetics, safety, and immunogenicity of SCT510 were equivalent to bevacizumab (Avastin^®). As a proposed biosimilar drug to bevacizumab, SCT510 was well tolerated in healthy Chinese males.

CLINICAL TRIALS REGISTRATION

NCT05113511.

A phase I study comparing the biosimilarity of the pharmacokinetics and safety of recombinant humanized anti-vascular endothelial growth factor monoclonal antibody injection with Avastin® in healthy Chinese male subjects

BACKGROUND

The biosimilar landscape for malignancies continues to grow, with several biosimilars for reference product bevacizumab currently available. Bevacizumab has been shown to be well tolerated; however, the safety of recombinant humanized anti-vascular endothelial growth factor (VEGF) monoclonal antibody injection remains unclear. This study aimed to compare the pharmacokinetics (PK), safety, and immunogenicity of recombinant humanized anti-VEGF monoclonal antibody injection to that of Avastin® in healthy Chinese male volunteers.

METHODS

A randomized, double-blind, single-dose, and parallel-group study was performed on 88 healthy men who randomly (1:1) received either the test drug as an intravenous infusion of 3 mg/kg or Avastin®. The primary PK parameter was area under the serum concentration-time curve (AUC) from time zero to last quantifiable concentration (AUC_0-t). Secondary endpoints included maximum observed serum concentration (C_max), AUC from 0 extrapolated to infinity (AUC_inf), safety, and immunogenicity. Serum bevacizumab concentrations were measured using a validated enzyme-linked immunosorbent assay (ELISA).

RESULTS

The baseline characteristics were similar among the two groups. The 90% confidence interval (CI) for the geometric mean ratio of AUC_0-t, C_max and AUC_inf between the test group and reference group were 91.71%-103.18%, 95.72%-107.49% and 91.03%-103.43%, respectively. These values were within the predefined bioequivalence margin of 80.00%-125.00%, demonstrating the biosimilarity of the test drug and Avastin®. Eighty-one treatment-emergent adverse events were reported, with a comparable incidence among the test group (90.91%) and the reference group (93.18%). No serious adverse events were reported. The incidence of ADA antibodies in the two groups was low and similar.

CONCLUSION

In healthy Chinese men, PK similarity of recombinant humanized anti-VEGF monoclonal antibody injection to Avastin® was confirmed, with comparable safety and immunogenicity. Subsequent studies should investigate recombinant humanized anti-VEGF monoclonal antibody injection in patients setting.

TRIAL REGISTRATION

Registered 08/10/2019, CTR20191923.

A randomized, double-blind, single-dose, parallel phase I clinical trial to compare the bioequivalence, immunogenicity and safety of bevacizumab biosimilar and bevacizumab in healthy Chinese subjects

BACKGROUND

Bevacizumab, a humanized monoclonal antibody against VEGF, can be used as a target therapy for colorectal cancer. A phase I clinical trial was conducted to compare the bioequivalence, immunogenicity and safety of bevacizumab biosimilar (Chia Tai Tianqing Pharmaceutical Group Co., Ltd.) and Bevacizumab (Roche Diagnostics GmbH) in healthy Chinese males.

RESEARCH DESIGN & METHOD

Healthy Chinese subjects (N = 98) were randomly divided into two groups. A single-dose bevacizumab biosimilar or Bevacizumab was given for per cycle. Plasma drug concentrations were detected by liquid chromatography-tandem mass spectrometry (LC-MC/MS) assay. We detected the levels of anti-drug antibody (ADA) to evaluate drug immunogenicity and the safety of drugs throughout the study.

RESULTS

The geometric mean ratios (GMRs) of AUC_0-t, C_max and AUC_0-∞ for bevacizumab biosimilar and Bevacizumab were 96.27%, 93.69% and 97.01%, respectively. The 90% CIs were all within 80%-125%, meeting the bioequivalence standards. The levels of ADA were similar. In addition, the two drugs both demonstrated excellent safety in the trial.

CONCLUSION

This study showed that bevacizumab biosimilar and Bevacizumab had similar pharmacokinetics (PK) parameters and safety in healthy Chinese subjects.

CLINICAL TRIAL REGISTRATION INFORMATION

This trial was registered in ClinicalTrials.gov (Number: NCT05476341, date registered: 25, Jul 2022) and Drug Clinical Trial Registration and Information Disclosure Platform (Number: CTR20171308, date registered: 16, Nov 2017).

A randomized phase I study comparing the pharmacokinetics of a bevacizumab (HD204) biosimilar to European Union- and United States of America-sourced bevacizumab

PURPOSE

This first-in-human study was designed to evaluate the pharmacokinetic (PK) equivalence between HD204 and the European Union (EU)-sourced bevacizumab, between HD204 and the United States of America (US)-sourced bevacizumab, and between EU-sourced and US-sourced bevacizumab (NCT03390673).

METHODS

In this randomized, double-blind, 3-way parallel group, single-dose comparative PK study, healthy male subjects were randomized to receive a single 1 mg/kg intravenous dose of HD204, EU-sourced bevacizumab or US-sourced bevacizumab. PK parameters were calculated using non-compartmental methods. PK equivalence was determined using the pre-defined equivalence margin of 0.8-1.25 in terms of AUC(0-∞) for the pairwise comparisons.

FINDINGS

Baseline demographics for the 119 randomized subjects were similar across the three groups. The 90% CIs for the ratio of the geometric means of HD204 to US-sourced bevacizumab, HD204 to EU-sourced bevacizumab, and EU-sourced to US-sourced bevacizumab were all within the interval of 80% to 125% for AUC0-inf, thus demonstrating equivalency in the PK properties for all three treatment groups. Similarly, the ratio of the geometric means for AUC0-last and Cmax were all within the 80% and 125% margins, supporting the robustness of the primary findings. All other PK parameters, including the half-life (t1⁄2) clearance (CL), volume of distribution (Vd) and time of maximum concentration (tmax), were comparable. There was no difference between the 3 treatment arms in terms of vital signs, laboratory tests and adverse events. None of the subjects treated with HD204 had positive ADA results.

IMPLICATIONS

HD204 demonstrates equivalent pharmacokinetic profiles compared to those of both US-sourced and EU-sourced bevacizumab. (NCT03390673).

Pharmacokinetic bioequivalence, safety, and immunogenicity of GB222, a bevacizumab biosimilar candidate, and bevacizumab in Chinese healthy males: a randomized clinical trial

BACKGROUND

This study was conducted to compare the similarity of the pharmacokinetics (PKs), safety, and immunogenicity of GB222, a potential bevacizumab biosimilar, to that of reference bevacizumab in Chinese healthy males.

RESEARCH DESIGN AND METHODS

This was a randomized, double-blind, single-dose, parallel-group clinical trial performed in 84 Chinese healthy males, who were randomly assigned to receive a single infusion dose of 1 mg/kg GB222 or bevacizumab with an 84-days follow-up. The primary endpoint was the area under the plasma concentration-time curve (AUC) from zero to the last quantifiable concentration at time t (AUC_0-t). The second endpoints were the safety and immunogenicity evaluation. The PK bioequivalence was verified by the 90% confidence intervals (CIs) of the geometrical mean (GM) ratio for AUC_0-t falling within the bioequivalence margin, 80-125%.

RESULTS

The PK profiles of GB222 and bevacizumab were comparable. The 90% CIs of GM ratio of GB222 to bevacizumab for AUC_0-t was within the pre-specified bioequivalence margin. The most common treatment-related adverse event was sinus bradycardia. Seventeen subjects (20.2%) tested positive for anti-drug antibodies (ADAs).

CONCLUSION

GB222 was found to be comparable to bevacizumab in terms of PKs, safety, and immunogenicity for Chinese healthy males.

TRIAL REGISTRATION

ChiCTR-IIR-17,011,143.

A randomized, single-dose, pharmacokinetic equivalence study comparing MB02 (proposed biosimilar) and reference bevacizumab in healthy Japanese male volunteers

Purpose

MB02 is a biosimilar to bevacizumab that has demonstrated similar physicochemical and functional properties in in vitro studies to the reference bevacizumab (Avastin^®). This study aims to assess the pharmacokinetic (PK) similarity of MB02 to the reference bevacizumab in Japanese population.

Methods

This double-blind, randomized, parallel-group, single-dose PK study, was performed in healthy Japanese male volunteers. Subjects were equally randomized (1:1) to receive a single (3 mg/kg) IV dose of MB02 or reference bevacizumab. PK assessments were done up to 70 days post-dose. Non-compartmental parameters were calculated. PK similarity was determined using predefined equivalence range (0.80–1.25) for the area under the serum concentration–time curve from time 0 extrapolated to infinity (AUC_0–∞). Immunogenicity samples were taken pre-dose and up to day 70. Safety was assessed throughout the study.

Results

In total, 48 subjects (24 in each treatment group) were dosed. Consequently to the observed similar PK profile, the 90% confidence interval for the geometric means ratio for the primary PK endpoint, AUC_0–∞, was within the predefined equivalence range (0.981–1.11). Forty-seven treatment-emergent adverse events (TEAEs) were reported in 20 subjects (41.7%) with comparable incidence among MB02 and reference bevacizumab groups (22 and 25, respectively), none of them was severe or serious. Anti-drug antibodies incidence was low and similar between treatment groups.

Conclusions

Pharmacokinetic similarity of MB02 to reference bevacizumab was evidenced in Japanese healthy subjects, with comparable safety and immunogenicity profile between treatments. This study supports the biosimilarity of MB02 to reference bevacizumab in Japanese population. ClinicalTrials.gov identifier: NCT04238650.

A phase 1 randomized study compare the pharmacokinetics, safety and immunogenicity of HLX04 to reference bevacizumab sourced from the United States, the European Union, and China in healthy Chinese male volunteers

Purpose

To compare the pharmacokinetic profiles, safety and immunogenicity of proposed bevacizumab biosimilar HLX04 with reference bevacizumab in healthy Chinese males.

Methods

In this double-blind Phase 1 study, healthy volunteers (N = 208) were randomized 1:1:1:1 to a single 3 mg/kg intravenous infusion of HLX04 or reference bevacizumab sourced from the United States (bevacizumab-US), the European Union (bevacizumab-EU) or China (bevacizumab-CN). Co-primary endpoints were area under the serum concentration–time profile (AUC) from time zero extrapolated to infinity (AUC_0–inf) and from zero to last quantifiable concentration (AUC_last). Secondary endpoint was the maximum serum drug concentration (C_max). Study participants were monitored for treatment-emergent adverse events (TEAEs) and samples were collected for anti-drug antibody (ADA) testing throughout the study.

Results

Pharmacokinetic parameters were similar across groups. The respective geometric least-squares mean ratios (GLSMR) of AUC_0–inf, AUC_last and C_max were: 95.7%, 96.0% and 101.8% for HLX04 versus bevacizumab-US; 94.3%, 94.6% and 100.5% for HLX04 versus bevacizumab-EU; and 90.0%, 90.4% and 98.2% for HLX04 versus bevacizumab-CN. For all test-to-reference comparisons, two-sided 90% confidence intervals of GLSMR for AUC_0–inf, AUC_last and C_max fell in the pre-specified bioequivalence range (80–125%). There were no notable differences in the frequency, nature and/or grade of TEAEs. No deaths were reported and no ADAs were detected during the study.

Conclusion

HLX04 had similar safety and pharmacokinetic profiles to reference bevacizumab in healthy Chinese males, supporting the confirmatory Phase 3 study investigating the efficacy and safety equivalence between HLX04 and bevacizumab in patients with metastatic colorectal cancer (NCT03511963).

Clinical trial registration

The study was registered with Clinicaltrials.gov, NCT03483649.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04297-z.

A pharmacokinetics study of proposed bevacizumab biosimilar MYL-1402O vs EU-bevacizumab and US-bevacizumab

PURPOSE

Bevacizumab is a recombinant humanized monoclonal antibody that inhibits vascular endothelial growth factor-specific angiogenesis in some cancers. MYL-1402O is a proposed bevacizumab biosimilar.

METHODS

The primary objective of this single-center, randomized, double-blind, three-arm, parallel-group, phase 1 study in healthy male volunteers was to evaluate bioequivalence of MYL-1402O to EU and US-reference bevacizumab, and EU-reference bevacizumab to US-reference bevacizumab. The primary pharmacokinetic parameter was area under the serum concentration-time curve from 0 extrapolated to infinity (AUC_0-∞). Pharmacokinetic parameters were analyzed using general linear models of analysis of variance. Secondary endpoints included safety and tolerability.

RESULTS

Of 111 enrolled subjects, 110 were included in the pharmacokinetic analysis (MYL-1402O, n = 37; EU-reference bevacizumab, n = 36; US-reference bevacizumab, n = 37). Bioequivalence was demonstrated between MYL-1402O and EU-reference bevacizumab, MYL-1402O and US-reference bevacizumab, and between EU- and US-reference bevacizumab where least squares mean ratios of AUC_0-∞ were close to 1, and 90% CIs were within the equivalence range (0.80-1.25). Secondary pharmacokinetic parameters (AUC from 0 to time of last quantifiable concentration [AUC_0-t], peak serum concentration [C_max], time to C_max, elimination rate constant, and elimination half-life) were also comparable, with 90% CIs for ratios of AUC_0-t and C_max within 80-125%. Treatment-emergent adverse events were similar across all three treatment groups and were consistent with clinical data for bevacizumab.

CONCLUSION

MYL-1402O was well tolerated and demonstrated pharmacokinetic and safety profiles similar to EU-reference bevacizumab and US-reference bevacizumab in healthy male volunteers. No new significant safety issues emerged (ClinicalTrials.gov, NCT02469987; ClinicalTrialsRegister.eu EudraCT, 2014-005621-12; June 12, 2015).

Clinical and treatment characteristics of patients treated with the first therapeutic oncology biosimilars bevacizumab-awwb and trastuzumab-anns in the US

Background:

In July 2019, bevacizumab-awwb and trastuzumab-anns were marketed in the USA as the first therapeutic oncology biosimilars. We aimed to investigate the initial real-world use of bevacizumab-awwb and trastuzumab-anns for cancer management in US oncology practices.

Methods:

A retrospective, observational analysis of data from US cancer patients (⩾18 years of age) was carried out to describe the use of bevacizumab-awwb and trastuzumab-anns during the first 12 months following their market entry, using structured data from the Flatiron Health electronic health record-derived database.

Results:

A total of 2952 and 2997 patients with recorded use of bevacizumab-awwb and trastuzumab-anns, respectively, were included in the analysis. The first use of bevacizumab-awwb and trastuzumab-anns was in a patient with metastatic colorectal cancer (mCRC) within 10 days of market availability and in a patient with early stage breast cancer (eBC) within 4 days, respectively. The use of these biosimilars was observed across all approved cancer indications; 68% of bevacizumab-awwb users were those diagnosed with mCRC and 72% of trastuzumab-anns users were those diagnosed with eBC. Approximately half the patients were previously exposed to reference product (RP) prior to initiation of bevacizumab-awwb or trastuzumab-anns. Among pre-exposed patients, the majority received the biosimilars [bevacizumab-awwb (63–85%) or trastuzumab-anns (75–81%)] within 28 days of the last infusion of the RP. For both biosimilars, no major differences were observed in patient characteristics between RP-naïve and pre-exposed patients.

Conclusion:

Initial evidence from the first 12 months following market entry suggests rapid clinical adoption of bevacizumab-awwb and trastuzumab-anns across all approved tumor types. Usage of these two biosimilars was observed in both RP-naïve patients and patients who were previously treated with RP, with no distinctive differences in patient characteristics between the two groups.

A video abstract is available for this article as part of the Kanjintionline supplemental material.

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.

A phase I, randomized, single-dose pharmacokinetic study comparing sb8 (bevacizumab biosimilar) with reference bevacizumab in healthy volunteers

PURPOSE

To compare pharmacokinetics, safety, tolerability, and immunogenicity between SB8, a bevacizumab biosimilar, and the European Union (EU) and United States (US) reference products (bevacizumab-EU, bevacizumab-US).

METHODS

In this randomized, double-blind, parallel-group, and single-dose study, healthy volunteers were randomized to receive a 3 mg/kg dose of SB8, bevacizumab-EU, or bevacizumab-US via intravenous infusion. Primary endpoints were area under the concentration-time curve from time zero to infinity (AUC_inf) and to the last quantifiable concentration (AUC_last), and maximum observed serum concentration (C_max). Bioequivalence was achieved if 90% confidence intervals (CIs) for the ratios of the geometric least squares means (LSMeans) of primary endpoints were within the predefined bioequivalence margins of 80.00-125.00%. Safety and immunogenicity were also investigated.

RESULTS

The 90% CIs for the geometric LSMean ratios of AUC_inf, AUC_last and C_max were all within the prespecified bioequivalence margins. Geometric LSMean ratios for SB8/bevacizumab-EU, SB8/bevacizumab-US and bevacizumab-EU/bevacizumab-US were 88.01%, 88.48% and 100.54% for AUC_inf, 88.65%, 89.08% and 100.49% for AUC_last and 99.59%, 101.15% and 101.56% for C_max, respectively. Incidence of treatment-emergent adverse events (TEAEs) across treatment groups was comparable (SB8: 50.0%, bevacizumab-EU: 37.5%, bevacizumab-US: 53.8%). Most TEAEs were mild and considered as not related to the study drug. No deaths or treatment discontinuations due to adverse events occurred. Incidence of anti-drug antibodies was also comparable between all groups and no neutralizing antibodies were detected.

CONCLUSION

This study demonstrated pharmacokinetic bioequivalence and similar safety and immunogenicity profiles of SB8 to both reference products, bevacizumab-EU and bevacizumab-US, and of bevacizumab-EU to bevacizumab-US. CLINICALTRIALS.

GOV IDENTIFIER

NCT02453672 (submitted date); EudraCT number: 2015-001,026-41.

A Clinical Review of Biosimilars Approved in Oncology

Objective

To summarize and review the clinical data of Food and Drug Administration (FDA)-approved biosimilars for use in treatment of cancer and the current challenges health care institutions face when implementing a newly approved biosimilar.

Data Sources

A literature search of the following databases was performed between January 1, 2012, and December 31, 2019: PubMed, Google, and ClinicalTrials.gov. Search terms included the words biosimilar, bevacizumab, rituximab, and/or trastuzumab.

Study Selection and Data Extraction

Only primary literature on biosimilars with an ongoing or completed phase 3 trial and/or FDA approval were included in the final analysis. Primary literature consisted of peer-reviewed publications, published abstracts, and any results posted on the ClinicalTrials.gov database.

Data Synthesis

Clinical trials of FDA-approved biosimilars for bevacizumab, rituximab, and trastuzumab showed no significant differences with respect to efficacy, safety, and pharmacokinetics when compared with their reference products.

Relevance to Patient Care and Clinical Practice

The anticipated growth of biologics in oncology and the recent introduction of biosimilars over the past few years have placed a lot of emphasis on biosimilars as a significant source of cost savings for the health care system. Our article compiles and analyzes existing data on biosimilar efficacy, safety, and financial impact.

Conclusions

The major concerns of biosimilars revolve around their long-term efficacy and safety. Even with many questions to be answered, biosimilars have the potential for significant cost savings in the US health care system.

A randomized, double-blind, parallel-group, single‑dose, pharmacokinetic bioequivalence study of INTP24 and bevacizumab in healthy adult men

PURPOSE

To demonstrate pharmacokinetic (PK) equivalence and to compare safety of INTP24 (bevacizumab biosimilar) with that of US-bevacizumab and EU-bevacizumab in healthy male subjects.

METHODS

In this randomized, parallel-group, double-blind study, male subjects were randomized (1:1:1) to receive a single 1 mg/kg intravenous infusion of either INTP24, US-bevacizumab, or EU-bevacizumab. The primary endpoint was area under serum concentration (AUC) from time zero to infinity (AUC_0-∞). Secondary endpoints were AUC from time zero to last quantifiable concentration (AUC_0-t), maximum concentration (C_max), other PK parameters, immunogenicity, and safety.

RESULTS

A total of 117 subjects (39/group) were dosed; 113 subjects (37, 37, and 39 in INPT24, US-bevacizumab, and EU-bevacizumab groups, respectively) completed the study and were included in the PK analysis. Baseline demographics were similar across the three groups. The 90% confidence intervals (CI) of geometric mean ratios (GMR) of ln-transformed AUC_0-∞ and C_max of INTP24 relative to US-bevacizumab and EU-bevacizumab were within the acceptance range of 80%-125% (INTP24 vs. US-bevacizumab, 96.55-112.51% and 99.16-112.79%: INTP24 vs. EU-bevacizumab, 94.84-110.17% and 96.32-109.28%). The 90% CIs of GMRs for AUC_0-t was also within 80-125% for INTP24 vs. US-bevacizumab and INTP24 vs. EU-bevacizumab. Safety and immunogenicity profiles were similar across the three groups. Twenty-one (17.95%) subjects experienced at least one AE and 9 (7.69%) were ADA positive. One treatment-related serious adverse event (varicella zoster infection) was reported in INTP24 group.

CONCLUSION

This study demonstrated PK bioequivalence of INTP24 to US-bevacizumab and EU-bevacizumab in healthy male subjects and showed similar safety and immunogenicity profiles across the treatment groups.

A randomized, double-blind, single-dose study to evaluate the biosimilarity of QL1101 with bevacizumab in healthy male subjects

PURPOSE

This is the first study to compare the pharmacokinetics of QL1101, a proposed bevacizumab biosimilar, with Avastin^® sourced from Roche Diagnostics GmbH.

METHODS

In this double-blind, single-dose, parallel-group study, healthy male subjects were randomized 1:1 to receive QL1101 or Avastin^® 3 mg/kg intravenously. Pharmacokinetic assessments were conducted for 85 days, with additional safety and immunogenicity assessments until day 90. Primary study endpoints were area under the concentration-time curve (AUC) from time zero to infinity (AUC_0-∞), AUC from time zero to the last quantifiable concentration (AUC_0-last), and maximum serum concentration (C_max). Pharmacokinetic equivalence was shown if the 90% confidence intervals (CIs) of the geometric mean ratios (GMRs) of the C_0-max, AUC_0-last, and AUC_0-∞ were within the predefined bioequivalence margin of 80-125.00%.

RESULTS

A total of 82 subjects were randomized to the following groups: 42 to QL1101 and 40 to Avastin^®. The 90% CIs of the GMRs of AUC_0-∞, AUC_0-last, and C_max of QL1101 and Avastin® were (97.8%, 107.0%), (94.5%, 106.9%), and (94.1%, 107.3%), respectively, which were all within the bioequivalence margin. The incidence of adverse events was 90.5% and 95.0% in the QL1101 and Avastin® groups, respectively. Mean serum concentration-time profiles, secondary pharmacokinetic parameters, and safety and immunogenicity profiles were comparable across the two treatment groups.

CONCLUSIONS

The study demonstrated the pharmacokinetic equivalence of QL1101 to Avastin^®. QL1101 (3 mg/kg, iv) is safe and tolerable in healthy Chinese subjects. These data support the further clinical evaluation of QL1101 as a bevacizumab biosimilar.

Pivotal Considerations for Optimal Deployment of Healthy Volunteers in Oncology Drug Development

Oncology drug development is among the most challenging of any therapeutic area, with first-in-human trials expected to deliver information on both safety and activity. Until recently, therapeutic approaches in oncology focused on cytotoxic chemotherapy agents, ruling out even the possibility of enrolling normal healthy volunteers (NHVs) in clinical trials due to safety considerations. The emergence of noncytotoxic modalities, including molecularly targeted agents with more favorable safety profiles, however, has led to increasing numbers of clinical pharmacology studies of these agents being conducted in NHVs. Beyond rapid enrollment and cost savings, there are other advantages of conducting specific types of studies in NHVs with the goal of more appropriate dosing decisions in certain subsets of the intended patient populations, allowing for enrollment of such patients in therapeutic trials from which they might otherwise have been excluded. Nevertheless, the decision must be carefully weighed against potential disadvantages, and although the considerations surrounding conduct of clinical trials using NHVs are generally well-defined in most other therapeutic areas, they are less well-defined in oncology.

Analysis of Pharmacokinetic and Pharmacodynamic Parameters in EU- Versus US-Licensed Reference Biological Products: Are In Vivo Bridging Studies Justified for Biosimilar Development?

BACKGROUND

Bridging studies are mandatory in the EU and USA if the reference biological product used in the biosimilar comparability exercise is foreign sourced. However, it has been argued that the duplication of bridging studies may limit biosimilar development.

OBJECTIVE

The aim of the study was to explore whether it is necessary to conduct pharmacokinetic (PK)/pharmacodynamic (PD) bridging studies for biosimilars. This study examines similarities and differences between EU- and US-licensed reference biological products, based on literature-reported PK and/or PD data.

METHODS

We searched PubMed, Drugs@FDA, and European Medicines Agency (EMA) databases to identify biosimilar bridging studies designed to evaluate similarities between EU- and US-licensed reference biological products. PK and/or PD parameters were retrieved; the ratio of the parameter value of the EU-licensed product to that of the US-licensed product and its corresponding 90% confidence intervals (CIs) were calculated. Similarity was declared if the 90% CIs for the ratios of the PK or PD parameters were within the range of 80-125%.

RESULTS

Thirty-one bridging studies were identified for 11 biosimilars, including adalimumab (n = 10), bevacizumab (n = 4), epoetin alfa (n = 1), etanercept (n = 2), filgrastim (n = 1), infliximab (n = 3), insulin glargine (n = 1), insulin lispro (n = 1), PEGfilgrastim (n = 2), rituximab (n = 2), and trastuzumab (n = 4). Most studies showed PK and/or PD similarities between the EU- and US-licensed reference biological products. However, among the 31 studies, only three studies (accounting for two biologics, PEGfilgrastim and adalimumab) showed dissimilarity between the EU and US reference products. Although one bridging study on PEGfilgrastim (Sandoz) indicated dissimilar PKs (maximum observed plasma concentration [C_max] and area under the concentration-time curve [AUC]) between the reference products, the other study (Mylan) demonstrated similar PK. Moreover, two of ten studies involving adalimumab failed to demonstrate similarities between the reference products. However, for both cases, PK similarities were later confirmed in the follow-up bridging studies with larger sample sizes.

CONCLUSION

Our analysis reveals that, in most cases, the reference biological products originated from the EU and those from the USA are almost indistinguishable in terms of PK/PD properties. Additional in vivo bridging studies between reference products from different global regions may not be required if similar physicochemical and structural properties are evident in vitro.

Pharmacist perspectives and considerations for implementation of therapeutic oncology biosimilars in practice

Purpose

An overview of therapeutic oncology biosimilars, the U.S. biosimilars regulatory pathway, and the clinical development of selected biosimilar products is provided, including discussion of considerations in adopting biosimilars into oncology practice.

Summary

Biosimilars are biologic agents that are highly similar to and have no clinically meaningful differences from an approved reference product in terms of safety, purity, and potency. There is a large market for cancer biologics, and approval of biosimilars has the potential to increase access to care and reduce costs. An abbreviated regulatory pathway for the development and approval of biosimilars defines a stepwise approach to demonstrating biosimilarity and conducting clinical comparative trials to confirm equivalent pharmacokinetics, efficacy, safety, and immunogenicity to the reference product. Three therapeutic biologics (bevacizumab, trastuzumab, and rituximab) have been used extensively in the treatment of a variety of cancers and are targets for biosimilar product development. Preclinical and clinical experience with 2 recently approved biosimilars to bevacizumab and trastuzumab is reviewed. Challenges faced by pharmacy and therapeutics committees when considering oncology biosimilars for formulary inclusion are discussed.

Conclusion

Increased adoption of biosimilars could potentially lower treatment costs and improve access to biologics for patients with cancer. Key considerations in formulary review of biosimilars include the quality and quantity of data from comparative clinical trials, economic factors, manufacturer reliability, and challenges associated with incorporating biosimilars into practice.

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

ABP 215 (MVASI™) is the first approved biosimilar to Avastin® (bevacizumab). It is approved in the USA and the European Union (EU) for all bevacizumab indications in these jurisdictions except for ovarian cancer in the USA due to orphan drug exclusivity. ABP 215 was shown to be structurally, functionally and clinically (pharmacokinetic, efficacy and safety) similar to the bevacizumab reference product; the pharmacokinetic study was conducted in healthy adult men (n = 202); safety and efficacy were evaluated in patients with advanced nonsquamous non-small-cell lung cancer (n = 642). Together, these results comprise the totality of evidence that provides scientific justification for extrapolation to all approved indications of the reference product and supports the clinical value of ABP 215 as an additional treatment option.

A Phase I, Randomized, Single-Dose Study Evaluating the Biosimilarity of TAB008 to Bevacizumab in Healthy Volunteers

Objective: This study compared the pharmacokinetics (PK), safety, and immunogenicity of the biosimilar TAB008 monoclonal antibody to bevacizumab (Avastin^®) in normal healthy Chinese male volunteers.

Methods: In this randomized, double-blind, parallel controlled study, a total of 100 healthy Chinese male subjects were randomized (1:1) to receive a single 1 mg/kg intravenous dose of TAB008 or Avastin^® over a 90-min infusion. The subjects were followed for 99 days after drug administration. Primary endpoints were bioequivalence of major pharmacokinetic parameters (AUC_0-t and AUC_0-∞) and maximum observed serum concentration (C_max). Secondary endpoints included safety and immunogenicity parameters.

Results: The two groups of test subjects (49 subjects in the TAB008 group and 50 subjects in the Avastin^® group) were well matched in regards to all demographic and baseline characteristics. The treatment group ratios of LS geometric means for the three primary PK parameters were fully contained within the bioequivalence limits of 80.00–125.00% (90% CI was 103.66–118.33% for C_max, 94.32–111.72% for AUC_0-t, and 94.69–112.23% for AUC_0-∞). Treatment-emergent adverse events (TEAEs) were reported for 24 (49.0%) subjects in the TAB008 group and 22 (44.0%) subjects in the Avastin^® group. TEAEs related to the study drug were reported for 19 (38.8%) subjects in the TAB008 group and 19 (38.0%) subjects in the Avastin^® group. National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) Grade 3 TEAEs were reported for 1 (2.0%) subject in the TAB008 group and 3 (6.0%) subjects in the Avastin^® group. There were no Grade 4 or 5 TEAEs or serious adverse events (SAEs) during the study. Anti-drug antibody generation was reported once only in each group, and neutralizing antibody (Nab) analysis was negative upon follow-up.

Conclusion: TAB008 attained pharmacokinetic similarity to bevacizumab, and was safe and well tolerated.

Safety analysis of proposed pegfilgrastim biosimilar in Phase I and Phase III studies

Aim: This analysis compares safety data for Sandoz proposed biosimilar (LA-EP2006) and reference pegfilgrastim from a Phase I pharmacokinetic/pharmacodynamic study in healthy volunteers (HVs) and two Phase III confirmatory studies in patients with breast cancer (BC; total n = 808). Patients & methods: Baseline characteristics were summarized, and event rates of bone pain and headache calculated. Results: HVs in the Phase I pharmacokinetic/pharmacodynamic study were generally younger, with lower mean body mass index, versus BC patients in PROTECT-1/-2. Bone pain was the most frequent adverse event with similar incidences with reference versus proposed biosimilar in all studies. Conclusion: No differences in adverse events were found between Sandoz proposed biosimilar and reference pegfilgrastim, notwithstanding some differences between HVs and BC patients.

Reviewing the role of healthy volunteer studies in drug development

BACKGROUND

With the exception of genotoxic oncology drugs, first-in-human, Phase 1 clinical studies of investigational drugs have traditionally been conducted in healthy volunteers (HVs). The primary goal of these studies is to investigate the pharmacokinetics and pharmacodynamics of a novel drug candidate, determine appropriate dosing, and document safety and tolerability.

MAIN BODY

When tailored to specific study objectives, HV studies are beneficial to manufacturers and patients alike and can be applied to both non-oncology and oncology drug development. Enrollment of HVs not only increases study accrual rates for dose-escalation studies but also alleviates the ethical concern of enrolling patients with disease in a short-term study at subtherapeutic doses when other studies (e.g. Phase 2 or Phase 3 studies) may be more appropriate for the patient. The use of HVs in non-oncology Phase 1 clinical trials is relatively safe but nonetheless poses ethical challenges because of the potential risks to which HVs are exposed. In general, most adverse events associated with non-oncology drugs are mild in severity, and serious adverse events are rare, but examples of severe toxicity have been reported. The use of HVs in the clinical development of oncology drugs is more limited but is nonetheless useful for evaluating clinical pharmacology and establishing an appropriate starting dose for studies in cancer patients. During the development of oncology drugs, clinical pharmacology studies in HVs have been used to assess pharmacokinetics, drug metabolism, food effects, potential drug-drug interactions, effects of hepatic and renal impairment, and other pharmacologic parameters vital for clinical decision-making in oncology. Studies in HVs are also being used to evaluate biosimilars versus established anticancer biologic agents.

CONCLUSION

A thorough assessment of toxicity and pharmacology throughout the drug development process is critical to ensure the safety of HVs. With the appropriate safeguards, HVs will continue to play an important role in future drug development.

A randomized, single-blind, single-dose study to assess the pharmacokinetic equivalence of the biosimilar ABP 215 and bevacizumab in healthy Japanese male subjects

Purpose

Analytic, pharmacokinetic (PK), and clinical similarity between the biosimilar ABP 215 and bevacizumab has previously been demonstrated in global studies. Here we present a phase 1 study in healthy adult Japanese men.

Methods

This study was a randomized, single-blind, single-dose, parallel-group study comparing PK parameters of ABP 215 versus EU-authorized bevacizumab in healthy Japanese men. Primary endpoints were maximum observed serum concentration (C_max) and area under the serum concentration—time curve from time 0 to infinity (AUC_inf). Secondary endpoints included AUC from time 0 to time of last quantifiable concentration (AUC_last), safety, tolerability, and immunogenicity.

Results

Baseline characteristics were similar among study subjects (n = 24/group). After a 3-mg/kg intravenous infusion, the geometric means (GMs) of C_max, AUC_inf, and AUC_last were 71.2 µg/mL, 25,259 µg h/mL, and 22,499.3 µg h/mL, respectively, for ABP 215 and 70.16 µg/mL, 25,801 µg h/mL, and 22,604.6 µg h/mL, respectively, for bevacizumab. The GM ratios (90% confidence interval; CI) for C_max, AUC_inf, and AUC_last were 1.015 (0.946–1.088), 0.979 (0.914–1.049), and 0.995 (0.941–1.053) for ABP 215 versus bevacizumab. All CIs fell within the prespecified bioequivalence margin (0.80–1.25). Adverse events (AEs) occurred in 2/24 subjects receiving ABP 215 and 1/24 receiving bevacizumab. There were no deaths or AEs leading to study discontinuation; no subject was positive for binding anti-drug antibodies (ADAs).

Conclusions

ABP 215 and bevacizumab showed PK similarity in Japanese men. Safety profiles were comparable between the two groups. The pharmacokinetics in Japanese subjects were consistent with those in a previous global PK equivalence study.

A comparative pharmacokinetic study of DRL_BZ, a candidate biosimilar of bevacizumab, with Avastin® (EU and US) in healthy male subjects

AIM

The aim of this study was to compare the pharmacokinetics (PK) of DRL_BZ with that of EU-approved (reference medicinal product; RMP) and US-licensed (reference product; RP) bevacizumab (Avastin^® ) in healthy male subjects.

METHODS

In this double-blind, parallel-group, Phase 1 study (BZ-01-001), men aged 20-45 years were randomized 1:1:1 to receive a single intravenous infusion of 1 mg kg^-1 of bevacizumab as DRL_BZ, RMP or RP. A total of 149 subjects were randomized (DRL_BZ, 50; RMP, 50; RP, 49). Primary endpoints included maximum observed serum concentration (C_max ), area under the concentration-time curve from time zero (pre-dose) extrapolated to infinity (AUC_(0-∞) ), and area under the concentration-time curve from time zero (pre-dose) to last quantifiable concentration (AUC_(0-t) ). Secondary objectives were to compare the safety and immunogenicity of DRL_BZ with those of the reference products.

RESULTS

Primary PK parameters were comparable across groups, and 90% confidence intervals for the geometric mean ratios of the primary PK endpoints were within the pre-specified equivalence margins (80-125%) for all pairwise comparisons (DRL_BZ vs. RMP, DRL_BZ vs. RP and RMP vs. RP). No deaths or serious adverse events were reported. Similar numbers of subjects reported similar numbers of treatment-emergent adverse events in the three treatment groups. One subject who received DRL_BZ had anti-drug antibodies at the Day 85 visit; however, no anti-drug antibodies were detected in this subject at the 12-month follow-up visit.

CONCLUSIONS

PK, safety and immunogenicity of DRL_BZ were comparable to EU-approved and US-licensed bevacizumab in healthy male subjects.

Bevacizumab biosimilars: scientific justification for extrapolation of indications

The first biosimilar of bevacizumab was approved by the US FDA; other potential biosimilars of bevacizumab are in late-stage clinical development. Their availability offers opportunity for increased patient access across a number of oncologic indications. The regulatory pathway for biosimilar approval relies on the totality of evidence that includes a comprehensive analytical assessment, and a clinical comparability study in a relevant disease patient population. Extrapolation of indications for a biosimilar to other eligible indications held by the originator, in the absence of direct clinical comparison, frequently forms part of the regulatory judgment. Herein, we consider the evidence required to demonstrate biosimilarity for bevacizumab biosimilars, with particular focus on the rationale for extrapolation across oncologic indications.

Angiogenesis: Managing the Culprits behind Tumorigenesis and Metastasis

Deregulated angiogenesis has been identified as a key contributor in a number of pathological conditions including cancer. It is a complex process, which involves highly regulated interaction of multiple signalling molecules. The pro-angiogenic signalling molecule, vascular endothelial growth factor (VEGF) and its cognate receptor 2 (VEGFR-2), which is often highly expressed in majority of human cancers, plays a central role in tumour angiogenesis. Owing to the importance of tumour vasculature in carcinogenesis, tumour blood vessels have emerged as an excellent therapeutic target. The anti-angiogenic therapies have been shown to arrest growth of solid tumours through multiple mechanisms, halting the expansion of tumour vasculature and transient normalization of tumour vasculature which help in the improvement of blood flow resulting in more uniform delivery of cytotoxic agents to the core of tumour mass. This also helps in reduction of hypoxia and interstitial pressure leading to reduced chemotherapy resistance and more uniform delivery of cytotoxic agents at the targeted site. Thus, complimentary combination of different agents that target multiple molecules in the angiogenic cascade may optimize inhibition of angiogenesis and improve clinical benefit in the cancer patients. This review provides an update on the current trend in exploitation of angiogenesis pathways as a strategy in the treatment of cancer.