Final results and outcomes by prior bevacizumab exposure, skin toxicity, and hypomagnesaemia from ASPECCT: randomized phase 3 non-inferiority study of panitumumab versus cetuximab in chemorefractory wild-type KRAS exon 2 metastatic colorectal cancer

Clinical impact of hypomagnesemia induced by necitumumab plus cisplatin and gemcitabine treatment in patients with advanced lung squamous cell carcinoma: a subanalysis of the NINJA study

Background

The clinical impact of hypomagnesemia induced by necitumumab plus gemcitabine and cisplatin (GCN) as a second-line or later therapy is unclear.

Objective

We aimed to evaluate the clinical characteristics and survival impact of hypomagnesemia induced by this therapy.

Design

This was a sub-analysis of the retrospective multicenter NINJA study.

Methods

Among the 93 patients enrolled in the NINJA study, this subanalysis included 75 patients with baseline serum magnesium concentrations.

Results

The incidence of grade ⩾2 hypomagnesemia was 18.0% in the patients with normal baseline serum magnesium concentrations and 42.8% in those with low concentrations (p = 0.073). The discontinuation rates of GCN treatment owing to hypomagnesemia in each group were 0% and 7.1%, respectively (p = 0.187). The number of necitumumab doses and severity of hypomagnesemia were positively correlated (r = 0.389, p < 0.001). Patients who developed hypomagnesemia in fewer than 21 days after the first dose of GCN (n = 12) had significantly poorer progression-free survival (PFS) than those without the condition (n = 63; median: 4.1 vs 4.4 months, p = 0.048). A similar trend was observed for OS (median: 9.7 vs 15.7 months, p = 0.062). These results were maintained after multivariate analyses (PFS: hazard ratio (HR) 2.46, p = 0.014; OS: HR 2.78, p = 0.021).

Conclusion

GCN as a second-line or later therapy may be tolerable regardless of the patient's baseline serum magnesium concentration. On the other hand, early serum magnesium reduction with this therapy is associated with a poor prognosis. However, caution should be needed because our results lacked sufficient information for confounding variables other than those analyzed here that may influence the correlation between hypomagnesemia and survival.

Analysis of EGFR binding hotspots for design of new EGFR inhibitory biologics

The epidermal growth factor (EGF) receptor (EGFR) is activated by the binding of one of seven EGF-like ligands to its ectodomain. Ligand binding results in EGFR dimerization and stabilization of the active receptor conformation subsequently leading to activation of downstream signaling. Aberrant activation of EGFR contributes to cancer progression through EGFR overexpression/amplification, modulation of its positive and negative regulators, and/or activating mutations within EGFR. EGFR targeted therapeutic antibodies prevent dimerization and interaction with endogenous ligands by binding the ectodomain of EGFR. However, these antibodies have had limited success in the clinic, partially due to EGFR ectodomain resistance mutations, and are only applicable to a subset of patients with EGFR-driven cancers. These limitations suggest that alternative EGFR targeted biologics need to be explored for EGFR-driven cancer therapy. To this end, we analyze the EGFR interfaces of known inhibitory biologics with determined structures in the context of endogenous ligands, using the Rosetta macromolecular modeling software to highlight the most important interactions on a per-residue basis. We use this analysis to identify the structural determinants of EGFR targeted biologics. We suggest that commonly observed binding motifs serve as the basis for rational design of new EGFR targeted biologics, such as peptides, antibodies, and nanobodies.

Comparison of systemic treatments for previously treated patients with unresectable colorectal liver metastases: a systematic review and network meta-analysis

Background

There is limited evidence of comparative results among different treatments for patients with unresectable colorectal liver metastases (CRLM) who have failed at least one line of previous systemic therapy. We aimed to compare the efficacy of systemic treatments among these patients through this investigation.

Methods

We collected randomized controlled trials (RCTs) reported in English up until July 2023, from databases including PubMed, Embase, Cochrane Library, ClinicalTrials.gov, and prominent conference databases, for this Bayesian network meta-analysis. Phase II or III trials that evaluated at least two therapeutic regimens were included. Primary outcome was overall survival (OS), secondary outcome was progression-free survival (PFS). Hazards ratios (HRs) with 95% confidence intervals (CIs) were used as effect size. Subgroup analysis was performed based on metastatic sites. The current systematic review protocol was registered on PROSPERO (CRD42023420498).

Results

30 RCTs were included, with a total of 13,511 patients. Compared to chemotherapy, multi-targeted therapy (HR 0.57, 95% CI 0.37-0.87) and targeted therapy plus chemotherapy (HR 0.78, 95% CI 0.67-0.91) show significant advantages. Targeted therapy (HR 0.92, 95% CI 0.54-1.57) and local treatment plus chemotherapy (HR 1.03, 95% CI 0.85-1.23) had comparable performance. For patients with liver metastases, TAS-102 plus bevacizumab, aflibercept plus fluorouracil-based combination chemotherapy (CTFU), and bevacizumab plus capecitabine-based combination chemotherapy (CTCA) showed the best outcomes in terms of OS. Bevacizumab plus intensified CTFU, bevacizumab plus CTCA, and HAI followed by single-agent chemotherapy (SingleCT) performed the best regarding PFS. For patients with liver-limited metastases, aflibercept plus CTFU is the optimal choice in OS. For PFS, the best options were HAI followed by SingleCT, aflibercept plus CTFU, and panitumumab plus CTFU. For patients with multiple-site metastases, the best treatments were TAS-102 plus bevacizumab, bevacizumab plus CTCA, bevacizumab plus CTFU, and aflibercept plus CTFU.

Conclusion

Multi-targeted therapy and targeted therapy plus chemotherapy are the best treatment mechanisms. TAS-102 plus bevacizumab is superior in OS, the combination of anti-VEGF drugs like bevacizumab and aflibercept with standard chemotherapy is the preferred option for CRLM patients.

The effective combination therapies with irinotecan for colorectal cancer

Colorectal cancer is the third most common type of cancer worldwide and has become one of the major human disease burdens. In clinical practice, the treatment of colorectal cancer has been closely related to the use of irinotecan. Irinotecan combines with many other anticancer drugs and has a broader range of drug combinations. Combination therapy is one of the most important means of improving anti-tumor efficacy and overcoming drug resistance. Reasonable combination therapy can lead to better patient treatment options, and inappropriate combination therapy will increase patient risk. For the colorectal therapeutic field, the significance of combination therapy is to improve the efficacy, reduce the adverse effects, and improve the ease of treatment. Therefore, we explored the clinical advantages of its combination therapy based on mechanism or metabolism and reviewed the rationale basis and its limitations in conducting exploratory clinical trials on irinotecan combination therapy, including the results of clinical trials on the combination potentiation of cytotoxic drugs, targeted agents, and herbal medicine. We hope that these can evoke more efforts to conduct irinotecan in the laboratory for further studies and evaluations, as well as the possibility of more in-depth development in future clinical trials.

Efficacy, safety and genomic analysis of SCT200, an anti-EGFR monoclonal antibody, in patients with fluorouracil, irinotecan and oxaliplatin refractory RAS and BRAF wild-type metastatic colorectal cancer: a phase Ⅱ study

BACKGROUND

Limited therapeutic options are available for metastatic colorectal cancer (mCRC) patients after failure of first- and second-line therapies, representing an unmet medical need for novel therapies.

METHODS

This is an open-label, single arm, multicenter, phase Ⅱ study aiming to perform the efficacy, safety and genomic analysis of SCT200, a noval fully humanized IgG1 anti-epidermal growth factor receptor (EGFR) monoclonal antibody, in patients with fluorouracil, irinotecan and oxaliplatin refractory RAS and BRAF wild-type mCRC. SCT200 (6 mg/kg) was given weekly for the first six weeks, followed by a higher dose of 8 mg/kg every two weeks until disease progression or unacceptable toxicity. Primary endpoint was independent review committee (IRC)-assessed objective response rate (ORR) and secondary endpoints included ORR in patients with left-sided tumor, disease control rate (DCR), duration of response (DoR), time to response (TTR), progression-free survival (PFS), overall survival (OS) and safety.

FINDINGS

From February 12, 2018 to December 1, 2019, a total of 110 patients aged between 26 and 77 years (median: 55; interquartile range [IQR]: 47-63) with fluorouracil, oxaliplatin, and irinotecan refractory RAS and BRAF wild-type mCRC were enrolled from 22 hospitals in China. As the data cut-off date on May 15, 2020, the IRC-assessed ORR and DCR was 31% (34/110, 95% confidence interval [CI] 22-40%) and 75% (82/110, 95% CI 65-82%), respectively. Thirty one percent (34/110) patients achieved confirmed partial response (PR). The median PFS and median OS were 5.1 months (95% CI 3.4-5.2) and 16.2 months (95% CI 11.1-not available [NA]), respectively. The most common ≥ grade 3 treatment-related adverse events (TRAEs) were hypomagnesemia (17%, 19/110) and acneiform dermatitis (11%, 12/110). No deaths occurred. Genomic analysis suggested positive association between MYC amplification and patients' response (P = 0.0058). RAS/RAF mutation and MET amplification were the most frequently detected resistance mechanisms. Patients with high circulating tumor DNA (ctDNA) at baseline or without ctDNA clearance at the 7th week after the first dose of SCT200 administration before receiving SCT200 had worse PFS and OS.

INTERPRETATION

SCT200 exhibited promising clinical efficacy and manageable safety profiles in RAS and BRAF wild-type mCRC patients progressed on fluorouracil, irinotecan and oxaliplatin treatment. The baseline ctDNA and ctDNA clearance status at the 7th week after the first dose of SCT200 administration before receiving SCT200 could be a potential prognostic biomarker for RAS and BRAF wild-type mCRC patients with SCT200 therapy.

FUNDING

This study was sponsored by Sinocelltech Ltd., Beijing, China and partly supported by the National Science and Technology Major Project for Key New Drug Development (2019ZX09732001-006, 2017ZX09304015).

A comparison of panitumumab and cetuximab in the treatment of KRAS wild-type metastatic colorectal cancer: a systematic review and meta-analysis

AIM

Cetuximab and panitumumab are common antibodies against epidermal growth factor receptor (EGFR) that can be used in combination with chemotherapy for the treatment of metastatic colorectal cancer (mCRC). Although these two drugs are considered to be very similar, differences in the efficacy and safety of cetuximab and panitumumab are still unclear. We conducted this meta-analysis to explore the effects and adverse reactions of cetuximab and panitumumab in the treatment of mCRC.

METHODS

We searched PubMed, the Cochrane Library, Embase, Web of Science, China national knowledge infrastructure (CNKI) and WanFang databases to identify records related to the efficacy and safety of cetuximab and panitumumab in the treatment of mCRC. The search terms were "cetuximab," "panitumumab," and "colorectal cancer." The deadline of searching was April 2022. Review manager 5.4 software was used to perform the statistical analysis for this meta-analysis. Pooled hazard ratio (HR) with 95% confidence intervals (CI) were calculated to evaluate the overall survival (OS) and progression free survival (PFS) of cetuximab and panitumumab in the treatment of mCRC.

RESULTS

There was no significant difference in OS, PFS, and response rate (RR) between cetuximab arm and panitumumab arm (OS: HR = 0.91, 95% CI = 0.81-1.03, p = .14; PFS: HR = 0.92, 95% CI = 0.83-1.02, p = .11; RR: OR = 1.22, 95% CI = 0.96-1.61, p = .14). We also did not observe any statistical difference between both arms in incidence of acneiform rash, severe acneiform rash, diarrhea, and severe diarrhea (acneiform rash: OR = 1.09, 95% CI = 0.84-1.42, p = .51; severe acneiform rash: OR = 1.50, 95% CI = 0.80-2.81, p = .21; diarrhea: OR = 1.08, 95% CI = 0.82-1.42, p = .58; severe diarrhea: OR = 0.90, 95% CI = 0.44-1.84, p = .77). The incidence of paronychia was decreased in the panitumumab arm, but that of hypomagnesemia and severe hypomagnesemia were decreased in the cetuximab arm. (paronychia: OR = 0.74, 95% CI = 0.55-1.00, p = .05; hypomagnesemia: OR = 1.85, 95% CI =1.41-2.41, p < .00001; severe hypomagnesemia: OR = 2.66, 95% CI = 1.52-4.67, p = .0006).

CONCLUSION

There was no significant difference in OS, PFS and RR between the cetuximab arm and panitumumab arm in the treatment of mCRC. For adverse reactions, the incidence of paronychia was decreased in the panitumumab arm, and the incidence of hypomagnesemia was deceased in the cetuximab arm.

A phase Ia dose-escalation trial of Ametumumab (a fully human monoclonal antibody against epidermal growth factor receptor) in patients with advanced solid malignancies

Background:

Epidermal growth factor receptor (EGFR) is a well-known target for cancer treatment. However, the authorized anti-EGFR monoclonal antibodies generally cause several toxic effects, especially severe cutaneous toxicities as well as infusion reactions, and the clinical indications are limited. Here we developed Ametumumab, a fully human recombinant anti-EGFR monoclonal antibody.

Objectives:

To assess the safety, tolerability, pharmacokinetics (PK), and immunogenicity of Ametumumab.

Design:

A first-in-human phase Ia dose escalation study of Ametumumab in patients with advanced solid malignancies.

Methods:

An open-label, first-in-human dose escalation study was done in 22 patients with advanced malignancies who received six ascending dosages ranging from 75 to 750 mg/m2. Following a single dosage and a 28-day dose-limiting toxicity (DLT) monitoring period, patients were given repeated doses weekly. Blood samples were taken to determine the PK parameters of Ametumumab and anti-drug antibody concentrations. Every 8 weeks, radiographic tumor evaluations were conducted.

Results:

In this trial, no DLT was observed, and the maximum tolerated dose was not reached at doses up to 750 mg/m2. There were no severe adverse events but mild and moderate adverse effects, such as headache, proteinuria, and rash. Single-dose PK results demonstrated a straightforward linear relationship with dosage escalation. The medication concentrations accumulated and attained steady-state after four rounds of injections. It was calculated that 10 patients with disease control would be observed in the 22 evaluable patients. The disease control rate was 45.5%.

Conclusion:

The Ametumumab was well tolerated and safe in patients with advanced solid malignancies, exhibiting minimal immunogenicity, a long half-life, high levels of drug exposure in the blood, and preliminary effectiveness.

Registration:

The trial was registered with CTR20170343 on 10 April 2017, The China Center for Drug Evaluation.

The Validity of Surrogate Endpoints in Sub Groups of Metastatic Colorectal Cancer Patients Defined by Treatment Class and KRAS Status

Background and Aim: Findings from the literature suggest that the validity of surrogate endpoints in metastatic colorectal cancer (mCRC) may depend on a treatments' mechanism of action. We explore this and the impact of Kirsten rat sarcoma (KRAS) status on surrogacy patterns in mCRC. Methods: A systematic review was undertaken to identify randomized controlled trials (RCTs) for pharmacological therapies in mCRC. Bayesian meta-analytic methods for surrogate endpoint evaluation were used to evaluate surrogate relationships across all RCTs, by KRAS status and treatment class. Surrogate endpoints explored were progression free survival (PFS) as a surrogate endpoint for overall survival (OS), and tumour response (TR) as a surrogate for PFS and OS. Results: 66 RCTs were identified from the systematic review. PFS showed a strong surrogate relationship with OS across all data and in subgroups by KRAS status. The relationship appeared stronger within individual treatment classes compared to the overall analysis. The TR-PFS and TR-OS relationships were found to be weak overall but stronger within the Epidermal Growth Factor Receptor + Chemotherapy (EGFR + Chemo) treatment class; both overall and in the wild type (WT) patients for TR-PFS, but not in patients with the mutant (MT) KRAS status where data were limited. Conclusions: PFS appeared to be a good surrogate endpoint for OS. TR showed a moderate surrogate relationship with PFS and OS for the EGFR + Chemo treatment class. There was some evidence of impact of the mechanism of action on the strength of the surrogacy patterns in mCRC, but little evidence of the impact of KRAS status on the validity of surrogate endpoints.

Prevention of Acne-Like Eruption Caused by Panitumumab Treatment through Oral Administration of Non-steroidal Anti-inflammatory Drugs

Acne-like eruption caused by anti-epidermal growth factor receptor (EGFR) antibodies such as panitumumab reduces treatment adherence and patient QOL; an alternative therapy is desired. Meanwhile, the usefulness of oral Non-steroidal Anti-inflammatory Drugs (NSAIDs) for acne-like eruptions caused by low-molecular-weight EGFR inhibitors such as erlotinib has been reported in the treatment of lung cancer. This study aimed to investigate whether the combined use of oral NSAIDs and panitumumab for colorectal cancer patients helps prevent acne-like eruption. We retrospectively investigated 167 colorectal cancer patients who had been treated with panitumumab for three cycles or more. The observation period was set from the start of panitumumab treatment to the end of three cycles. Within this period, the incidence and severity of acne-like eruptions were compared. A total of 59 and 108 patients were in the NSAIDs use and non-use groups, respectively, showing differences in the incidence of acne-like eruption rates (78.0 vs. 90.7%, respectively; p = 0.033). In the use group, eruption severity grades 0, 1, 2, and 3 were observed in 13, 33, 13, and 0 patients, respectively; the corresponding values in the non-use group were 10, 60, 36, and 2, respectively (p = 0.007). Oral NSAIDs may help prevent acne-like eruptions caused by panitumumab.

Diagnosis and Treatment of ERBB2-Positive Metastatic Colorectal Cancer: A Review

Importance

Amplification of ERBB2 (formerly referred to as HER2) is present in nearly 3% of patients with metastatic colorectal cancer overall and 5% of patients with KRAS and NRAS wild-type tumors. Despite the availability of several ERBB2-targeted therapeutic options for patients with ERBB2-positive breast and gastric/gastroesophageal tumors, to date, there are currently no approved therapies for patients with ERBB2-positive metastatic colorectal cancer, although ERBB2-targeted therapies are recommended in National Comprehensive Cancer Network guidelines. Recent evidence indicates that anti-ERBB2 therapeutic strategies are active in patients with ERBB2-positive metastatic colorectal cancer and could potentially represent a new standard-of-care.

Observations

The protein ERBB2 is a member of a family of epidermal growth factor receptors that also includes epidermal growth factor receptor (ERBB1), ERBB3, and ERBB4. Amplification of ERBB2 leads to overexpression of the ERBB2 tyrosine kinase receptor, resulting in aberrant signaling and cell migration, growth, adhesion, and differentiation. Colorectal tumors that harbor ERBB2 amplification are more likely to originate on the left side of the colon, are associated with primary and acquired resistance to anti-epidermal growth factor receptor therapies, and have increased incidence of central nervous system metastases. Using immunohistochemistry, fluorescence in situ hybridization, next-generation sequencing, and liquid biopsy techniques, several randomized clinical trials have evaluated the efficacy of ERBB2-targeted therapies in patients with ERBB2-positive metastatic colorectal cancer. These therapies include monoclonal antibodies, antibody-drug conjugates, and tyrosine kinase inhibitors, many of which were associated with favorable efficacy and safety profiles when treating patients with ERBB2-positive metastatic colorectal cancer.

Conclusions and Relevance

The results of this review suggest the ERBB2 receptor is a promising target for patients with metastatic colorectal cancer; however, to date, no therapies are approved for use in this patient population. Therefore, it is imperative to continue to work to address this unmet need so that patients with ERBB2-positive metastatic colorectal cancer have therapeutic options should they become refractory to treatment with standard therapies.

Epidermal Growth Factor Receptor Inhibitor-Induced Hypomagnesaemia: Is There a Best Replacement Strategy?

Monoclonal antibodies targeting the epidermal growth factor receptor (EGFRI), such as cetuximab and panitumumab, are commonly used systemic therapies for advanced colorectal and head and neck cancers. Hypomagnesaemia is a common side effect of these therapies and occurs in up to 30% of patients. Interruption of EGFR signalling in the distal convoluted tubule leads to inactivation of the transcellular transporter transient receptor potential channel melastatin member 6 and increased renal magnesium excretion. This paper describes the incidence, risk factors, and the emerging management options for EGFRI-induced hypomagnesaemia.

The Right Partner in Crime: Unlocking the Potential of the Anti-EGFR Antibody Cetuximab via Combination With Natural Killer Cell Chartering Immunotherapeutic Strategies

Cetuximab has an established role in the treatment of patients with recurrent/metastatic colorectal cancer and head and neck squamous cell cancer (HNSCC). However, the long-term effectiveness of cetuximab has been limited by the development of acquired resistance, leading to tumor relapse. By contrast, immunotherapies can elicit long-term tumor regression, but the overall response rates are much more limited. In addition to epidermal growth factor (EGFR) inhibition, cetuximab can activate natural killer (NK) cells to induce antibody-dependent cellular cytotoxicity (ADCC). In view of the above, there is an unmet need for the majority of patients that are treated with both monotherapy cetuximab and immunotherapy. Accumulated evidence from (pre-)clinical studies suggests that targeted therapies can have synergistic antitumor effects through combination with immunotherapy. However, further optimizations, aimed towards illuminating the multifaceted interplay, are required to avoid toxicity and to achieve better therapeutic effectiveness. The current review summarizes existing (pre-)clinical evidence to provide a rationale supporting the use of combined cetuximab and immunotherapy approaches in patients with different types of cancer.

Safety and efficacy of panitumumab in combination with trifluridine/tipiracil for pre-treated patients with unresectable, metastatic colorectal cancer with wild-type RAS: The phase 1/2 APOLLON study

BACKGROUND

We aimed to assess the safety and efficacy of combination treatment with panitumumab plus trifluridine/tipiracil (FTD/TPI) in patients with wild-type RAS metastatic colorectal cancer (mCRC) who were refractory/intolerant to standard therapies other than anti-epidermal growth factor receptor therapy.

METHODS

APOLLON was an open-label, multicentre, phase 1/2 trial. In the phase 1 part, 3 + 3 de-escalation design was used to investigate the recommended phase 2 dose (RP2D); all patients in the phase 2 part received the RP2D. The primary endpoint was investigator-assessed progression-free survival (PFS) rate at 6 months. Secondary endpoints included PFS, overall survival (OS), overall response rate (ORR), disease control rate (DCR), time to treatment failure (TTF), and safety.

RESULTS

Fifty-six patients were enrolled (phase 1, n = 7; phase 2, n = 49) at 25 Japanese centres. No dose-limiting toxicities were observed in patients receiving panitumumab (6 mg/kg every 2 weeks) plus FTD/TPI (35 mg/m2 twice daily; days 1-5 and 8-12 in a 28-day cycle), which became RP2D. PFS rate at 6 months was 33.3% (90% confidence interval [CI] 22.8-45.3). Median PFS, OS, ORR, DCR, and TTF were 5.8 months (95% CI 4.5-6.5), 14.1 months (95% CI 12.2-19.3), 37.0% (95% CI 24.3-51.3), 81.5% (95% CI 68.6-90.8), and 5.8 months (95% CI 4.29-6.21), respectively. Neutrophil count decreased (47.3%) was the most common Grade 3/4 treatment-emergent adverse event. No treatment-related deaths occurred.

CONCLUSION

Panitumumab plus FTD/TPI exhibited favourable anti-tumour activity with a manageable safety profile and may be a therapeutic option for pre-treated mCRC patients.

Predictive and prognostic value of magnesium serum level in FOLFIRI plus cetuximab or bevacizumab treated patients with stage IV colorectal cancer: results from the FIRE-3 (AIO KRK-0306) study

Magnesium wasting is a frequent side effect of epidermal growth factor receptor (EGFR)-antibody treatment as magnesium-absorption mechanisms are dependent on EGFR signaling. EGFR-inhibition results in decreased renal reabsorption. There is evidence that hypomagnesemia during cetuximab treatment correlates with response. The prognostic role of hypomagnesemia during bevacizumab treatment has not been studied yet. Here, we evaluate the prognostic value of hypomagnesemia in patients with metastatic colorectal cancer treated with FOLFIRI plus cetuximab or bevacizumab as first-line therapy. A total of 391 of 752 patients of the firstline irinotecan study population had magnesium levels measured at baseline and for the first three cycles (6 weeks) of treatment. Of those, 240 had Rat Sarkoma wildtype tumors. Overall hypomagnesemia was more common in the cetuximab compared to the bevacizumab arm (80 vs. 43%, P < 0.005). During therapy, magnesium showed a time-dependent decrease to 80% of baseline in the cetuximab and to 89% in the bevacizumab arm. Whereas magnesium continued to decrease over time in the cetuximab-treated patients, it remained stable in the bevacizumab-treated. Overall response rate (ORR) was associated with higher magnesium at week 6 (20.9 vs. 79.1%, P = 0.041). Bevacizumab-treated patients with magnesium levels below the median value at week 6 had a significantly longer progression-free survival (PFS; 11.7 vs. 9.9 months, P = 0.034; hazard ratio 0.73) and a trend towards longer overall survival (OS) (29.6 vs. 23.2 months, P = 0.089; hazard ratio 0.77). Hypomagnesemia at predefined time points and magnesium nadir had no significant effect on ORR, OS and PFS in the cetuximab arm. Our data show different magnesium kinetics in patients with metastatic colorectal cancer treated with cetuximab or bevacizumab. For patients treated with cetuximab, hypomagnesemia did not have an impact on response and survival. Hypomagnesemia might have a prognostic value in bevacizumab treatment.

Combination of Metformin, Sodium Oxamate and Doxorubicin Induces Apoptosis and Autophagy in Colorectal Cancer Cells via Downregulation HIF-1α

Colorectal cancer (CRC) is the third leading cause of cancer-related death worldwide in both sexes. Current therapies include surgery, chemotherapy, and targeted therapy; however, prolonged exposure to chemical agents induces toxicity in patients and drug resistance. So, we implemented a therapeutic strategy based on the combination of doxorubicin, metformin, and sodium oxamate called triple therapy (Tt). We found that Tt significantly reduced proliferation by inhibiting the mTOR/AKT pathway and promoted apoptosis and autophagy in CRC derived cells compared with doxorubicin. Several autophagy genes were assessed by western blot; ULK1, ATG4, and LC3 II were overexpressed by Tt. Interestingly, ULK1 was the only one autophagy-related protein gradually overexpressed during Tt administration. Thus, we assumed that there was a post-transcriptional mechanism mediating by microRNAs that regulate UKL1 expression during autophagy activation. Through bioinformatics approaches, we ascertained that ULK1 could be targeted by mir-26a, which is overexpressed in advanced stages of CRC. In vitro experiments revealed that overexpression of mir-26a decreased significantly ULK1, mRNA, and protein expression. Contrariwise, the Tt recovered ULK1 expression by mir-26a decrease. Due to triple therapy repressed mir-26a expression, we hypothesized this drug combination could be involved in mir-26a transcription regulation. Consequently, we analyzed the mir-26a promoter sequence and found two HIF-1α transcription factor recognition sites. We developed two different HIF-1α stabilization models. Both showed mir-26a overexpression and ULK1 reduction in hypoxic conditions. Immunoprecipitation experiments were performed and HIF-1α enrichment was observed in mir-26a promoter. Surprisingly, Tt diminished HIF-1α detection and restored ULK1 mRNA expression. These results reveal an important regulation mechanism controlled by the signaling that activates HIF-1α and that in turn regulates mir-26a transcription.

Navigating metastatic colorectal treatment options in the USA: a survey of patient acceptance of skin toxicities associated with Vectibix

Abstract

Purpose

To understand the extent to which metastatic colorectal cancer (mCRC) patients receive education on the prevention and management associated with skin rash following Vectibix treatment. Furthermore, to investigate how this adverse event affects a patient’s quality of life (QoL) and influences their treatment decisions.

Methods

A cross-sectional survey was administered to 200 mCRC patients (100 Vectibix users and 100 Vectibix non-users). After excluding respondents who had used cetuximab, 61 Vectibix users and 56 Vectibix non-users remained.

Results

Most Vectibix users (79%) experienced a skin rash in response to treatment of which 65% considered the rash moderate, 27% mild, and 8% severe. Vectibix users generally felt they were adequately informed about the rash (83%), with the most common messages received related to sun protection. However, sunscreen was used by only 42% of patients prior to rash and 60% of patients following the appearance of rash. The use of oral antibiotics was low prior to rash (21%) and following rash (46%). Among patients experiencing a rash within the past week (n=16), 75% reported the rash had a large negative impact on their QoL based on the Dermatology Life Quality Index.

Conclusion

There was a disconnect between patients feeling they were adequately informed and use of prevention and management strategies such as sun protection. This suggests a gap in patient education and adoption currently exists on management strategies both prior to and following the appearance of rash. Given the negative impact that skin toxicity has on the patient’s quality of life, it is essential that patients receive and subsequently utilize all information that can minimize rash severity.

Colon Cancer, Version 2.2021, NCCN Clinical Practice Guidelines in Oncology

This selection from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Colon Cancer focuses on systemic therapy options for the treatment of metastatic colorectal cancer (mCRC), because important updates have recently been made to this section. These updates include recommendations for first-line use of checkpoint inhibitors for mCRC, that is deficient mismatch repair/microsatellite instability-high, recommendations related to the use of biosimilars, and expanded recommendations for biomarker testing. The systemic therapy recommendations now include targeted therapy options for patients with mCRC that is HER2-amplified, or BRAF V600E mutation-positive. Treatment and management of nonmetastatic or resectable/ablatable metastatic disease are discussed in the complete version of the NCCN Guidelines for Colon Cancer available at NCCN.org. Additional topics covered in the complete version include risk assessment, staging, pathology, posttreatment surveillance, and survivorship.

Diagnosis and Treatment of Metastatic Colorectal Cancer: A Review

IMPORTANCE

Colorectal cancer (CRC) is the third most common cause of cancer mortality worldwide with more than 1.85 million cases and 850 000 deaths annually. Of new colorectal cancer diagnoses, 20% of patients have metastatic disease at presentation and another 25% who present with localized disease will later develop metastases.

OBSERVATIONS

Colorectal cancer is the third most common cause of cancer mortality for men and women in the United States, with 53 200 deaths projected in 2020. Among people diagnosed with metastatic colorectal cancer, approximately 70% to 75% of patients survive beyond 1 year, 30% to 35% beyond 3 years, and fewer than 20% beyond 5 years from diagnosis. The primary treatment for unresectable metastatic CRC is systemic therapy (cytotoxic chemotherapy, biologic therapy such as antibodies to cellular growth factors, immunotherapy, and their combinations.) Clinical trials completed in the past 5 years have demonstrated that tailoring treatment to the molecular and pathologic features of the tumor improves overall survival. Genomic profiling to detect somatic variants is important because it identifies the treatments that may be effective. For the 50% of patients with metastatic CRC with KRAS/NRAS/BRAF wild-type tumors, cetuximab and panitumumab (monoclonal antibodies to the epithelial growth factor receptor [EGFR]), in combination with chemotherapy, can extend median survival by 2 to 4 months compared with chemotherapy alone. However, for the 35% to 40% of patients with KRAS or NRAS sequence variations (formerly termed mutations), effective targeted therapies are not yet available. For the 5% to 10% with BRAF V600E sequence variations, targeted combination therapy with BRAF and EGFR inhibitors extended overall survival to 9.3 months, compared to 5.9 months for those receiving standard chemotherapy. For the 5% with microsatellite instability (the presence of numerous insertions or deletions at repetitive DNA units) or mismatch repair deficiency, immunotherapy may be used in the first or subsequent line and has improved treatment outcomes with a median overall survival of 31.4 months in previously treated patients.

CONCLUSIONS AND RELEVANCE

Advances in molecular profiling of metastatic CRC facilitate the ability to direct treatments to the biologic features of the tumor for specific patient subsets. Although cures remain uncommon, more patients can anticipate extended survival. Genomic profiling allows treatment selection so that more patients derive benefit and fewer are exposed to toxicity from ineffective therapies.

Mechanisms coupling sodium and magnesium reabsorption in the distal convoluted tubule of the kidney

Hypomagnesaemia is a common feature of renal Na+ wasting disorders such as Gitelman and EAST/SeSAME syndrome. These genetic defects specifically affect Na+ reabsorption in the distal convoluted tubule, where Mg2+ reabsorption is tightly regulated. Apical uptake via TRPM6 Mg2+ channels and basolateral Mg2+ extrusion via a putative Na+ -Mg2+ exchanger determines Mg2+ reabsorption in the distal convoluted tubule. However, the mechanisms that explain the high incidence of hypomagnesaemia in patients with Na+ wasting disorders of the distal convoluted tubule are largely unknown. In this review, we describe three potential mechanisms by which Mg2+ reabsorption in the distal convoluted tubule is linked to Na+ reabsorption. First, decreased activity of the thiazide-sensitive Na+ /Cl- cotransporter (NCC) results in shortening of the segment, reducing the Mg2+ reabsorption capacity. Second, the activity of TRPM6 and NCC are determined by common regulatory pathways. Secondary effects of NCC dysregulation such as hormonal imbalance, therefore, might disturb TRPM6 expression. Third, the basolateral membrane potential, maintained by the K+ permeability and Na+ -K+ -ATPase activity, provides the driving force for Na+ and Mg2+ extrusion. Depolarisation of the basolateral membrane potential in Na+ wasting disorders of the distal convoluted tubule may therefore lead to reduced activity of the putative Na+ -Mg2+ exchanger SLC41A1. Elucidating the interconnections between Mg2+ and Na+ transport in the distal convoluted tubule is hampered by the currently available models. Our analysis indicates that the coupling of Na+ and Mg2+ reabsorption may be multifactorial and that advanced experimental models are required to study the molecular mechanisms.

The effectiveness of cetuximab and panitumumab when combined with FOLFIRI in second-line treatment of KRAS wild type metastatic colorectal cancers. Single centre experience

Panitumumab and cetuximab are monoclonal antibodies known to be effective in metastatic colorectal cancer (mCRC). Although the survival benefits when combined with chemotherapy have been determined, there are no studies comparing the two agents with chemotherapy in the second-line treatment. In this study, we aimed to compare the efficacy of cetuximab vs panitumumab in patients who previously received chemotherapy. Who progressed after first-line treatment for K-ras wild type mCRC were analyzed. The efficacy of cetuximab vs panitumumab on overall survival (OS) and progression-free survival (PFS) when combined with FOLFIRI regimen was compared retrospectively. Median PFS was 6.9 months in the cetuximab group and 4.7 months in the panitumumab group. Median OS cetuximab and panitumumab groups were 18.4 and 12.2 months, respectively. In the second-line treatment of K-ras wild type mCRC, both PFS and OS were found to be longer in patients receiving cetuximab than in patients receiving panitumumab, but no statistically significant difference was found.

Current Options for Third-line and Beyond Treatment of Metastatic Colorectal Cancer. Spanish TTD Group Expert Opinion

Colorectal cancer (CRC) is a public health problem: it is the third most common cancer in men (746,000 new cases/year) and the second in women (614,000 new cases/year), representing the second leading cause of death by cancer worldwide. The survival of patients with metastatic CRC (mCRC) has increased prominently in recent years, reaching a median of 25 to 30 months. A growing number of patients with mCRC are candidates to receive a treatment in third line or beyond, although the optimal drug regimen and sequence are still unknown. In this situation of refractoriness, there are several alternatives: (1) To administer sequentially the 2 oral drugs approved in this indication: trifluridine/tipiracil and regorafenib, which have shown a statistically significant benefit in progression-free survival and overall survival with a different toxicity profile. (2) To administer cetuximab or panitumumab in treatment-naive patients with RAS wild type, which is increasingly rare because these drugs are usually indicated in first- or second-line. (3) To reuse drugs already administered that were discontinued owing to toxicity or progression (oxaliplatin, irinotecan, fluoropyrimidine, antiangiogenics, anti-epidermal growth factor receptor [if RAS wild-type]). High-quality evidence is limited, but this strategy is often used in routine clinical practice in the absence of alternative therapies especially in patients with good performance status. (4) To use specific treatments for very selected populations, such as trastuzumab/lapatinib in mCRC human epidermal growth factor receptor 2-positive, immunotherapy in microsatellite instability, intrahepatic therapies in limited disease or primarily located in the liver, although the main recommendation is to include patients in clinical trials.

Modern Approaches to Testing Drug Sensitivity of Patients' Tumors (Review)

Drug therapy is still one of the basic techniques used to treat cancers of different etiology. However, tumor resistance to drugs is a pressing problem limiting drug treatment efficacy. It is obvious for both modern fundamental and clinical oncology that there is the need for an individual approach to treating cancer taking into account the biological properties of a tumor when prescribing chemo- and targeted therapy. One of the promising strategies is to increase the antitumor therapy efficacy by developing predictive tests, which enable to evaluate the sensitivity of a particular tumor to a specific drug or a drug combination before the treatment initiation and, thus, make individual therapy selection possible. The present review considers the main approaches to drug sensitivity assessment of patients' tumors: molecular genetic profiling of tumor cells, and direct efficiency testing of the drugs on tumor cells isolated from surgical or biopsy material. There were analyzed the key directions in research and clinical studies such as: the search for predictive molecular markers, the development of methods to maintain tumor cells or tissue sections viable, i.e. in a condition maximum close to their physiological state, the development of high throughput systems to assess therapy efficiency. Special attention was given to a patient-centered approach to drug therapy in colorectal cancer.

Efficacy of Panitumumab and Cetuximab in Patients with Colorectal Cancer Previously Treated with Bevacizumab; a Combined Analysis of Individual Patient Data from ASPECCT and WJOG6510G

Background: Phase-III ASPECCT and randomised phase-II WJOG6510G trials demonstrated the noninferiority of panitumumab, when compared with cetuximab, for overall survival in patients with chemotherapy-refractory wild-type KRAS exon 2 metastatic colorectal cancer. Methods: The subgroup that received bevacizumab either prior to panitumumab or cetuximab monotherapy (ASPECCT) or in combination with irinotecan (WJOG6510G) was included. Multivariate Cox models were created, including the treatment arms as covariates together with patient, disease and treatment characteristics. Results: We included 185 and 189 patients in the panitumumab and cetuximab arms, respectively. The median overall survival was 12.8 and 10.1 months [p = 0.0031; log-rank test, stratified by trial; hazard ratio (HR), 0.72; 95% confidence interval (CI), 0.58–0.90], and the median progression-free survival was 4.7 and 4.1 months, in the panitumumab and cetuximab arms, respectively (p = 0.0207; HR, 0.79; 95% CI, 0.64–0.97). The treatment regimen was an independent prognostic factor of overall survival (adjusted HR, 0.69; 95% CI, 0.54–0.87; p = 0.0013). Conclusions: Panitumumab significantly prolonged the overall survival and progression-free survival, when compared with cetuximab in the cohort that previously received bevacizumab in the included studies. Clinical Trial Registration: ASPECCT trial registered with ClinicalTrials.gov (NCT01001377) and WJOG6510G trial registered with UMIN-CTR (UMIN000006643).

Randomised phase II study of panitumumab plus irinotecan versus cetuximab plus irinotecan in patients with KRAS wild-type metastatic colorectal cancer refractory to fluoropyrimidine, irinotecan and oxaliplatin (WJOG 6510G)

BACKGROUND

Cetuximab has been shown to be clinically active when given in combination with irinotecan in patients with irinotecan-refractory metastatic colorectal cancer (mCRC). However, it has remained unclear whether panitumumab is effective when combined with irinotecan. We compared efficacies of both regimens in this randomised phase II study.

PATIENTS AND METHODS

Patients with wild-type KRAS exon 2 mCRC previously treated with fluorouracil-, oxaliplatin- and irinotecan-based chemotherapies were randomised (1:1) to either panitumumab plus irinotecan (panitumumab arm) or cetuximab plus irinotecan (cetuximab arm). The primary end-point was progression-free survival (PFS). The planned sample size was 120, expecting a hazard ratio (HR) of 1.0 with non-inferiority margin of 1.3 (one-sided alpha error 0.2 and power 0.7). Major secondary end-points were overall survival (OS), response rate and safety.

RESULTS

From December 2011 to September 2014, 121 patients were enrolled, and 61 and 59 patients were randomised to the panitumumab and cetuximab arms, respectively (1 patient excluded). Most patients (97%) had received prior chemotherapies containing bevacizumab. The median PFS was 5.42 months in the panitumumab arm and 4.27 months in the cetuximab arm (HR = 0.64, 95% confidence interval [CI] = 0.44-0.94, P < 0.001 for non-inferiority, P = 0.058 for superiority), and median OS was 14.85 and 11.53 months (HR = 0.66, 95% CI = 0.44-1.00, P = 0.050 for superiority), respectively. The incidence of grade 3 or 4 hypomagnesaemia was higher in the panitumumab arm than that in the cetuximab arm (17% vs. 7%).

CONCLUSION

Panitumumab may be non-inferior to cetuximab in combination with irinotecan in survival of patients with irinotecan-refractory mCRC.

Current and New Predictors for Treatment Response in Metastatic Colorectal Cancer. The Role of Circulating miRNAs as Biomarkers

Colorectal cancer (CRC) is the third most frequently diagnosed cancer in the world. More than half of all CRC patients will eventually develop metastases and require treatment accordingly, but few validated predictive factors for response to systemic treatments exist. In order to ascertain which patients benefit from specific treatments, there is a strong need for new and reliable biomarkers. We conducted a comprehensive search using the PUBMED database, up to December 2019, in order to identify relevant studies on predictive biomarkers for treatment response in metastatic CRC. We will herein present the currently used and potential biomarkers for treatment response and bring up-to-date knowledge on the role of circulating microRNAs, associated with chemotherapy and targeted therapy regimens used in metastatic CRC treatment. Molecular, tumor-related, disease-related, clinical, and laboratory predictive markers for treatment response were identified, mostly proposed, with few validated. Several circulating microRNAs have already proven their role of prediction for treatment response in CRC, but future clinical studies are needed to confirm their role as biomarkers across large cohorts of patients.

Management of EGFR Inhibitor-induced Skin Toxicity and Factors Impacting Patients' Adherence to Skin Toxicity Treatment: Health Care Provider and Patient Surveys in European Oncology Centers

INTRODUCTION

This study aimed to provide a description of existing measures for the prevention and management of epidermal growth factor receptor inhibitor monoclonal antibody-induced skin toxicities and factors impacting patients' adherence to those measures in France, Germany, and Spain.

MATERIALS AND METHODS

The study consisted of 2 separate surveys. Health care professionals (HCPs; oncologists and nurses) in France, Germany, and Spain were interviewed, and patients with metastatic colorectal cancer and head-and-neck cancer in France and Germany self-completed questionnaires. The study was conducted between February and July 2018.

RESULTS

A total of 53 oncologists, 44 nurses, and 143 patients participated in the study. HCPs stated that skin toxicities moderately (52%) or severely (28%) impacted patient care. Ninety percent of HCPs reported routine provision of prophylactic measures. The great majority of patients self-reported adherence with the prophylactic (80% to 88% depending on the type of measures) and reactive (93% to drug prescription) skin toxicity recommendations. HCPs estimated patient adherence to be 45% for full adherence and 40% for partial adherence. Most HCPs reported a positive or very positive impact of preventive measures and recommendations on skin toxicity incidence and severity, patients' quality of life, and various aspects of quality of anti-cancer treatment.

CONCLUSIONS

Skin toxicities are an important adversity negatively impacting on patient care. However, despite the positive perception of the effectiveness of skin toxicity prophylaxis, almost one-third of oncology centers did not provide formal guidelines, and 10% of HCPs did not provide routine prophylactic measures. Patient adherence appears to be high for epidermal growth factor receptor inhibitor monoclonal antibody-induced skin toxicity prevention measures.

Current and emerging biomarkers in metastatic colorectal cancer

Background

The incorporation of novel biomarkers into therapy selection for patients with metastatic colorectal cancer (mcrc) has significantly improved outcomes. Optimal treatment planning now takes into account diverse characteristics of patients and their tumours to create personalized therapeutic plans.

Discussion

This review is split into two sections. In the first section, we review the prognostic and predictive significance of expanded RAS mutation testing, BRAF mutations, ERBB2 (her2) amplification, microsatellite instability (msi) and deficient mismatch repair (dmmr) protein, NTRK fusions, PIK3CA mutations, and met amplifications. The therapeutic implication of each of those biomarkers for personalizing therapies for each patient with mcrc is discussed. In the second section, we touch on testing methods and considerations of relevance to clinicians when they interpret companion diagnostics meant to guide therapy selection. The advantages and pitfalls of various methods are evaluated, and we also look at the potential of liquid biopsies and circulating tumour dna (ctdna) to change the landscape of therapeutic choice and biologic understanding of the disease.

Summary

Routine testing for extended RAS, BRAF, dmmr or high msi, and NTRK fusions is necessary to determine the best sequencing of chemotherapy and biologic agents for patients with mcrc. Although next-generation sequencing and ctdna are increasingly being adopted, other techniques such as immunohistochemistry retain their relevance in detection of her2 amplification, NTRK fusions, and dmmr.

Distinguishing Features of Cetuximab and Panitumumab in Colorectal Cancer and Other Solid Tumors

Cetuximab and panitumumab are two distinct monoclonal antibodies (mAbs) targeting the epidermal growth factor receptor (EGFR), and both are widely used in combination with chemotherapy or as monotherapy to treat patients with RAS wild-type metastatic colorectal cancer. Although often considered interchangeable, the two antibodies have different molecular structures and can behave differently in clinically relevant ways. More specifically, as an immunoglobulin (Ig) G1 isotype mAb, cetuximab can elicit immune functions such as antibody-dependent cell-mediated cytotoxicity involving natural killer cells, T-cell recruitment to the tumor, and T-cell priming via dendritic cell maturation. Panitumumab, an IgG2 isotype mAb, does not possess these immune functions. Furthermore, the two antibodies have different binding sites on the EGFR, as evidenced by mutations on the extracellular domain that can confer resistance to one of the two therapeutics or to both. We consider a comparison of the properties of these two antibodies to represent a gap in the literature. We therefore compiled a detailed, evidence-based educational review of the known molecular, clinical, and functional differences between the two antibodies and concluded that they are distinct therapeutic agents that should be considered individually during treatment planning. Available data for one agent can only partly be extrapolated to the other. Looking to the future, the known immune activity of cetuximab may provide a rationale for this antibody as a combination partner with investigational chemotherapy plus immunotherapy regimens for colorectal cancer.

Assessing the Justification, Funding, Success, and Survival Outcomes of Randomized Noninferiority Trials of Cancer Drugs: A Systematic Review and Pooled Analysis

Importance

Noninferiority trials test whether a new intervention is not worse than the comparator by a given margin.

Objectives

To study the characteristics of published randomized noninferiority trials in oncology with overall survival as an end point, to assess the association of justification and success in achieving noninferiority with the funding of these trials, and to evaluate the association of such trials with patient survival.

Data Sources

A systematic search of PubMed and Google Scholar databases was conducted in March 2018, with no date restrictions.

Study Selection

Randomized noninferiority trials of cancer drug therapies with overall survival as an end point were included. Trials of decision support, supportive care, and nondrug treatment in both arms were excluded.

Data Extraction and Synthesis

This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines for meta-epidemiological studies. Studies were screened for eligibility criteria, and data on criteria for noninferiority, funding, success (achieving noninferiority), and hazard ratios with confidence intervals for overall survival were extracted. Hazard ratios for overall survival were pooled across trials using a random-effects model.

Main Outcomes and Measures

Associations of the justification for using a noninferiority design and success in achieving noninferiority with the source of funding were assessed. Overall pooled hazard ratios and confidence intervals for overall survival were calculated.

Results

Among 74 noninferiority trials of cancer drug therapies, 23 (31%; enrolling 21 437 patients) used overall survival as the primary end point. The noninferiority margins for the hazard ratio of overall survival ranged from 1.08 to 1.33. Noninferiority design was justified in 14 trials (61%) but not in 9 (39%). Overall, 18 trials (78%) concluded with a finding of noninferiority. Industry funding was associated with lack of justification for noninferiority design (P = .02, assessed using the Fisher exact test) but not with success in proving noninferiority (P = .80, assessed using the Fisher exact test). When the hazard ratios across the trials were pooled, there was no beneficial or detrimental association with overall survival, with a pooled hazard ratio of 0.97 (95% CI, 0.92-1.02).

Conclusions and Relevance

The findings suggest that a substantial fraction of noninferiority trials in oncology, most of which are industry funded, lack justification for such a design. Greater attention to the use of noninferiority designs in randomized clinical trials of cancer drugs from local and national regulators is warranted.

Monitoring of cancer patients via next-generation sequencing of patient-derived circulating tumor cells and tumor DNA

Liquid biopsy of circulating tumor cells (CTC) and circulating tumor DNA (ctDNA) is gaining attention as a method for real-time monitoring in cancer patients. Conventional methods based upon epithelial cell adhesion molecule (EpCAM) expression have a risk of missing the most aggressive CTC subpopulations due to epithelial-mesenchymal transition and may, thus, underestimate the total number of actual CTC present in the bloodstream. Techniques utilizing a label-free inertial microfluidics approach (LFIMA) enable efficient capture of CTC without the need for EpCAM expression. In this study, we optimized a method for analyzing genetic alterations using next-generation sequencing (NGS) of extracted ctDNA and CTC enriched using an LFIMA as a first-phase examination of 30 patients with head and neck cancer, esophageal cancer, gastric cancer and colorectal cancer (CRC). Seven patients with advanced CRC were enrolled in the second-phase examination to monitor the emergence of alterations occurring during treatment with epidermal growth factor receptor (EGFR)-specific antibodies. Using LFIMA, we effectively captured CTC (median number of CTC, 14.5 cells/mL) from several types of cancer and detected missense mutations via NGS of CTC and ctDNA. We also detected time-dependent genetic alterations that appeared during anti-EGFR therapy in CTC and ctDNA from CRC patients. The results of NGS analyses indicated that alterations in the genomic profile revealed by the liquid biopsy could be expanded by using a combination of assays with CTC and ctDNA. The study was registered with the University Hospital Medical Information Network Clinical Trials Registry (ID: UMIN000014095).

Clinical Pharmacokinetics and Pharmacodynamics of the Epidermal Growth Factor Receptor Inhibitor Panitumumab in the Treatment of Colorectal Cancer

Despite progress in the treatment of metastatic colorectal cancer (mCRC) in the last 15 years, it is still a condition with a relatively low 5-year survival rate. Panitumumab, a fully human monoclonal antibody directed against the epidermal growth factor receptor (EGFR), is able to prolong survival in patients with mCRC. Panitumumab is used in different lines of therapy in combination with chemotherapy, and as monotherapy for the treatment of wild-type (WT) RAS mCRC. It is administered as an intravenous infusion of 6 mg/kg every 2 weeks and has a t_½ of approximately 7.5 days. Elimination takes place via two different mechanisms, and immunogenicity rates are low. Only RAS mutations have been confirmed as a negative predictor of efficacy with anti-EGFR antibodies. Panitumumab is generally well tolerated and has a manageable toxicity profile, despite a very high prevalence of dermatologic side effects. This article presents an overview of the clinical pharmacokinetics and pharmacodynamics of panitumumab, including a description of the studies that led to its approval in the different lines of therapy of mCRC.

Pan-Asian adapted ESMO consensus guidelines for the management of patients with metastatic colorectal cancer: a JSMO-ESMO initiative endorsed by CSCO, KACO, MOS, SSO and TOS

The most recent version of the European Society for Medical Oncology (ESMO) consensus guidelines for the treatment of patients with metastatic colorectal cancer (mCRC) was published in 2016, identifying both a more strategic approach to the administration of the available systemic therapy choices, and a greater emphasis on the use of ablative techniques, including surgery. At the 2016 ESMO Asia Meeting, in December 2016, it was decided by both ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special guidelines meeting, endorsed by both ESMO and JSMO, immediately after the JSMO 2017 Annual Meeting. The aim was to adapt the ESMO consensus guidelines to take into account the ethnic differences relating to the toxicity as well as other aspects of certain systemic treatments in patients of Asian ethnicity. These guidelines represent the consensus opinions reached by experts in the treatment of patients with mCRC identified by the Presidents of the oncological societies of Japan (JSMO), China (Chinese Society of Clinical Oncology), Korea (Korean Association for Clinical Oncology), Malaysia (Malaysian Oncological Society), Singapore (Singapore Society of Oncology) and Taiwan (Taiwan Oncology Society). The voting was based on scientific evidence and was independent of both the current treatment practices and the drug availability and reimbursement situations in the individual participating Asian countries.

L-Lactate dehydrogenase B may be a predictive marker for sensitivity to anti-EGFR monoclonal antibodies in colorectal cancer cell lines

Recently, proteins derived from cancer cells have been widely investigated as biomarkers for predicting the efficacy of chemotherapy. In this study, to identify a sensitive biomarker for the efficacy of anti-epidermal growth factor receptor monoclonal antibodies (anti-EGFR mAbs), proteins derived from 6 colorectal cancer (CRC) cell lines with different sensitivities to cetuximab, an anti-EGFR mAb, were analyzed. Cytoplasmic and membrane proteins extracted from each CRC cell line were digested using trypsin and analyzed comprehensively using mass spectrometry. As a result, 148 and 146 peaks from cytoplasmic proteins and 363 and 267 peaks from membrane proteins were extracted as specific peaks for cetuximab-resistant and -sensitive CRC cell lines, respectively. By analyzing the proteins identified from the peptide peaks, cytoplasmic L-lactate dehydrogenase B (LDHB) was detected as a marker of cetuximab sensitivity, and it was confirmed that LDHB expression was increased in cetuximab-resistant CRC cell lines. Furthermore, LDHB expression levels were significantly upregulated with the acquisition of resistance to cetuximab in cetuximab-sensitive CRC cell lines. In conclusion, LDHB was identified as an important factor affecting cetuximab sensitivity using comprehensive proteome analysis for the first time.

Comparative and combined effectiveness of innovative therapies in cancer: a literature review

To achieve therapeutic innovation in oncology, already expensive novel medicines are often concomitantly combined to potentially enhance effectiveness. While this aggravates the pricing problem, comparing effectiveness of novel yet expensive (concomitant) treatments is much needed for healthcare decision-making to deliver effective but affordable treatments. This study reviewed published clinical trials and real-world studies of targeted and immune therapies. In total, 48 studies compared and/or combined multiple novel products on breast, colorectal, lung and melanoma cancers. To a great extent, products evaluated in each study were owned by one manufacturer. However, cross-manufacturer assessments are also needed. Next to costs and intensive market competition, the absence of a regulatory framework enforcing real-world multiproduct studies prevents these from being conducted. Trusted third parties could facilitate such real-world studies, for which appropriate and efficient data access is needed.

Sequential therapy with bevacizumab and EGFR inhibitors for metastatic colorectal carcinoma: a national registry-based analysis

Purpose

Although inhibitors of vascular endothelial growth factor and inhibitors of epidermal growth factor receptor (EGFRi) are commonly used for the treatment of metastatic colorectal cancer (mCRC), the optimal sequencing of these agents is currently unclear.

Methods

A national registry of targeted therapies was used to analyze baseline characteristics and outcomes of patients with mCRC and wild-type KRAS exon 2 status who received bevacizumab and EGFRi (cetuximab or panitumumab) as a part of first- and second-line treatment in either sequence.

Results

The cohort included 490 patients (181 patients treated with first-line EGFRi and second-line bevacizumab and 309 patients treated with first-line bevacizumab and second-line EGFRi). Median overall survival (OS) from the initiation on first-line therapy was similar for patients treated with either sequence, reaching 31.8 (95% CI 27.5-36.1) vs 31.4 months (95% CI 27.8-35.0) for EGFRi → bevacizumab vs bevacizumab → EGFRi cohort, respectively. Time from first-line initiation to progression on the second-line therapy [progression-free survival (PFS)] was 21.1 (95% CI 19.3-23.0) vs 19.3 months (95% CI 17.3-21.3) for bevacizumab → EGFRi vs EGFRi → bevacizumab cohort, respectively (P=0.016).

Conclusion

This retrospective analysis of real-world data of patients with wild-type KRAS exon 2 mCRC showed no differences in OS between cohorts treated with bevacizumab → EGFRi vs the reverse sequence while combined PFS favored the bevacizumab → EGFRi sequence.

Cetuximab retreatment in patients with metastatic colorectal cancer who exhibited a clinical benefit in response to prior cetuximab: A retrospective study

Clinical benefits of cetuximab retreatment in patients with metastatic colorectal (mCRC) have been reported. In the present study, the effect of cetuximab retreatment on predictive markers was investigated by evaluating the clinical benefit of initial cetuximab treatment prior to cetuximab retreatment. Between November 2012 and March 2017, 14 patients with KRAS proto-oncogene GTPase exon 2 wild-type mCRC who exhibited a clinical benefit (confirmed stable disease for at least 6 months or a clinical response) to an initial cetuximab-based regimen, who received multiple lines of chemotherapy following disease progression and ultimately received a second cetuximab and irinotecan regimen, were retrospectively analyzed. For retreatment, patients received bi-weekly irinotecan (120-150 mg/m²) combined with cetuximab (400 mg/m² as an initial dose, followed by 250 mg/m², weekly). The median age of the 14 patients (11 males, 3 females) was 68 years (32-77). The median progression-free survival (PFS) following prior cetuximab-based therapy was 6.6 months (range, 4.1-18.4). Initial cetuximab treatment was administered as a first-line treatment in 11 patients, a second-line treatment in 1 patient and a third-line treatment in 2 patients. The median interval time between the last cycle of initial cetuximab-based therapy and the first cycle of cetuximab retreatment was 13.1 months (range, 6.0-37.1). The objective response rate of cetuximab retreatment was 21.4% and the median PFS was 4.4 months (95% confidence interval, 1.4-5.6). The Spearman's correlation coefficient for the PFS following retreatment and duration of initial cetuximab-based regimens demonstrated a more marked correlation compared with that between the PFS following retreatment and the interval time between the two regimens (r=0.45, P=0.11 vs. r=0.08, P=0.79). Cetuximab retreatment may provide clinical benefit to patients with mCRC who were good responders with longer periods of initial cetuximab-based therapy.

Phase III study with FOLFIRI + cetuximab versus FOLFIRI + cetuximab followed by cetuximab alone in RAS and BRAF WT mCRC

The optimal duration and intensity of first-line therapy in metastatic colorectal cancer patients once they have achieved an objective response is controversial. In a molecularly selected RAS and BRAF wild-type (wt) population, this concern is amplified. Once disease control has been achieved with a combination therapy including an anti-EGFR antibody, further exposure both to cytotoxic drugs and targeted therapy might result only in increased toxicity. In unresectable metastatic RAS and BRAF wt colorectal cancer patients, a deintensified therapy could represent a valuable option that might preserve quality of life. We designed a study to compare FOLFIRI/cetuximab to FOLFIRI/cetuximab for eight cycles followed by cetuximab alone in first-line treatment of RAS and BRAF (wt) metastatic colorectal cancer patients.

Panitumumab in the treatment of metastatic colorectal cancer, including wild-type RAS, KRAS and NRAS mCRC

The humanized monoclonal antibody panitumumab, targeted against EGFR, plays an important role in patients with metastatic colorectal cancer. This article reviews the body of evidence for panitumumab which demonstrates significant benefits across multiple lines of therapy in those without an extended RAS mutation. The use of panitumumab with RAS mutations is not beneficial and possibly harmful. Panitumumab is well tolerated with manageable toxicities. The role of panitumumab continues to evolve as understanding of sequencing of therapies grows. There is evidence for use as maintenance therapy and conversion therapy for unresectable liver metastases. Future research is likely to focus on biomarkers for improved patient selection and the development of novel therapeutic strategies to overcome resistance.

Final Analysis of Outcomes and RAS/BRAF Status in a Randomized Phase 3 Study of Panitumumab and Best Supportive Care in Chemorefractory Wild Type KRAS Metastatic Colorectal Cancer

INTRODUCTION

Tumor rat sarcoma gene (RAS) status is a negative predictive biomarker for anti-epidermal growth factor receptor (EGFR) therapy in metastatic colorectal cancer (mCRC). We analyzed outcomes according to RAS and v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutational status, and evaluated early tumor shrinkage (ETS) and depth of response (DpR) for patients with wild type RAS.

PATIENTS AND METHODS

Patients with confirmed metastatic colon or rectum adenocarcinoma, wild type Kristen rat sarcoma gene tumor exon 2 status, clinical/radiologic disease progression or toxicity during irinotecan or oxaliplatin treatment, and no previous anti-EGFR therapy were randomized 1:1 to receive best supportive care (BSC) with or without panitumumab (6.0 mg/kg, intravenously, on day 1 of each 14-day cycle) in this open-label, multicenter, phase III study (20100007). RAS and BRAF mutation status were determined using Sanger sequencing. ETS was evaluated as maximum percentage change from baseline to week 8; DpR was calculated as the percentage change for tumor shrinkage at nadir versus baseline.

RESULTS

Overall, 270 patients had RAS wild type mCRC (panitumumab with BSC, n = 142; BSC, n = 128). For patients with wild type RAS tumors, median overall survival (OS; hazard ratio [HR], 0.72; P = .015) and progression-free survival (PFS; HR, 0.45; P < .0001) were improved with panitumumab with BSC versus BSC. Similar improvements were seen for patients with wild type RAS, and wild type BRAF tumors (OS: HR, 0.75; P = .04; PFS: HR, 0.45; P < .0001). Median DpR was 16.9% for the evaluable panitumumab with BSC wild type RAS population. Overall, 69.5% experienced any type of tumor shrinkage at week 8; 38.2% experienced ≥ 20% shrinkage. Similar improvements in OS and PFS were seen with stratification according to ETS.

CONCLUSION

This analysis showed that panitumumab improved outcomes in wild type RAS mCRC and indicated that ETS and DpR could be used as additional efficacy markers.

Targeting the PI3K Signalling as a Therapeutic Strategy in Colorectal Cancer

Colorectal cancer (CRC) remains one of the leading causes of cancer mortality worldwide. Regarded as a heterogeneous disease, a number of biomarkers have been proposed to help in the stratification of CRC patients and to enable the selection of the best therapy for each patient towards personalized therapy. However, although the molecular mechanisms underlying the development of CRC have been elucidated, the therapeutic strategies available for these patients are still quite limited. Thus, over the last few years, a multitude of novel targets and therapeutic strategies have emerged focusing on deregulated molecules and pathways that are implicated in cell growth and survival. Particularly relevant in CRC are the activating mutations in the oncogene PIK3CA that frequently occur in concomitancy with KRAS and BRAF mutations and that lead to deregulation of the major signalling pathways PI3K and MAPK, downstream of EGFR. This review focus on the importance of the PI3K signalling in CRC development, on the current knowledge of PI3K inhibition as a therapeutic approach in CRC and on the implications PI3K signalling molecules may have as potential biomarkers and as new targets for directed therapies in CRC patients.

Protein biomarkers predictive for response to anti-EGFR treatment in RAS wild-type metastatic colorectal carcinoma

BACKGROUND

Metastatic colorectal cancer (mCRC) patients with mutant KRAS or NRAS are ineligible for anti-epidermal growth factor receptor (anti-EGFR) therapy, as RAS mutations activate downstream pathways independently of EGFR and induce primary resistance. However, even among RAS wild-type (WT) patients, only a fraction responds to anti-EGFR therapy, suggesting that other mechanisms of resistance exist. We hypothesise that different (epi)genetic alterations can lead to primary anti-EGFR resistance and that the crucial end point is the activation of protein signalling pathways.

METHODS

We analysed the expression and activation of proteins involved in cell signalling, using reverse phase protein arrays, on a multicentre French cohort of RAS WT mCRC treated with anti-EGFR treatment.

RESULTS

We identify activated EGFR and HER3 as protein biomarkers predictive for better overall survival. Active EGFR signalling and downstream PI3K, but not MAPK, pathway activation are associated with response to anti-EGFR treatment. Left-sided mCRC displays active ErbB2/3 and Wnt pathways and a better response to anti-EGFR therapy compared to right-sided mCRC.

CONCLUSIONS

We identify active EGFR and PI3K signalling as a key factor for response to anti-EGFR treatment in mCRC and highlight the importance of developing these biomarkers in clinical practice for the selection of RAS WT mCRC patients that would benefit from anti-EGFR treatment.

Long-term safety and survival outcomes from the Scandinavian Breast Group 2004-1 randomized phase II trial of tailored dose-dense adjuvant chemotherapy for early breast cancer

PURPOSE

Although adjuvant polychemotherapy improves outcomes for early breast cancer, the significant variability in terms of pharmacokinetics results in differences in efficacy and both short and long-term toxicities. Retrospective studies support the use of dose tailoring according to the hematologic nadirs.

METHODS

The SBG 2004-1 trial was a randomized feasibility phase II study which assessed tailored dose-dense epirubicin and cyclophosphamide (EC) followed by docetaxel (T) (group A), the same regimen with fixed doses (group B) and the TAC regimen (group C). Women aged 18-65 years, ECOG PS 0-1 with at least one positive axillary lymph node were randomized 1:1:1. The primary endpoint of the study was the safety and feasibility of the treatment. Toxicity was graded according to CTC-AE version 3.0. The design and short-term toxicity have been previously published. Here, we report safety and efficacy data after 10 years of follow-up.

RESULTS

A total of 124 patients were included in the study. After a median follow-up of 10.3 years, the probability for 10-year survival was 78.5, 75.1, and 63.4% and for relapse free survival 64.1, 71.0, and 59.5% for groups A, B, and C, respectively. There were no cases of clinically diagnosed cardiotoxicity or hematologic malignancies. No patient was lost to follow-up.

CONCLUSIONS

In this randomized phase II trial, tailored dose adjuvant chemotherapy was feasible, without an increased risk for long-term adverse events after a median follow-up of 10 years.

The current status of treatment for colorectal cancer in China: A systematic review

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers all over the world, but its epidemiology is obviously different in various regions.

METHODS

The treatment of CRC also has varying characteristics due to differences in economy, geography, disease onset, chemotherapy, and other factors, although international guidelines are used to guide the treatment of CRC in China.

RESULTS

This paper summarizes the current status of CRC treatment, including surgical therapy, neoadjuvant radiotherapy and chemotherapy, postoperative chemotherapy, targeted therapy, maintenance therapy, and immunotherapy, according to the clinical situation in China, so as to provide better therapy and improve clinical practice for patients with CRC.

CONCLUSION

This research shows that the treatment of colorectal cancer continues to progress, and the patient's efficacy and quality of life have improved.

RAS and BRAF in metastatic colorectal cancer management

The treatment of metastatic colorectal cancer (mCRC) has been further refined with the development of monoclonal antibodies, cetuximab and panitumumab, towards the epidermal growth factor receptor (EGFR). Anti-EGFR therapy has afforded improved survival in those with wild-type RAS mCRC but provides no benefit and even harm in those with RAS-mutant tumors. BRAF mutations have also been shown to predict lack of clinically meaningful benefit to anti-EGFR therapy in mCRC. Mechanisms of resistance to EGFR blockade in wild-type RAS or BRAF metastatic colorectal tumors appear to converge on the mitogen-activated protein kinase (MAPK) signaling pathway. Clinical trials involving combined BRAF, EGFR, and/or MAPK kinase (MEK) inhibition have shown promising activity in BRAF-mutant mCRC. Here, we review pivotal clinical trials that have redefined our treatment approach in mCRC with respect to anti-EGFR therapy based on RAS and BRAF mutation status. Future studies will likely focus on improving efficacy of anti-EGFR-based therapy in mCRC through sustained MAPK pathway inhibition.