Quantitative assessment of skin disorders induced by panitumumab: a prospective observational study

PURPOSE

Acneiform rash is frequently observed in patients undergoing cancer treatment with anti-epidermal growth factor receptor (EGFR) antibody drugs and can often necessitate treatment discontinuation. However, the specific changes in skin parameters resulting from anti-EGFR antibody drug administration are poorly understood. Therefore, this study aimed to longitudinally and quantitatively evaluate the changes in skin parameters (transepidermal water loss [TEWL], hydration level, and sebum level) caused by anti-EGFR antibody drugs and investigate their potential as control markers for skin disorders.

METHODS

This prospective study included 12 patients with colorectal cancer who received anti-EGFR antibody drugs for the first time. The assessment items included the grade of acneiform rash and skin parameters (TEWL, hydration level, and sebum level), which were observed for up to 6 weeks after administration of the medication.

RESULTS

The enrolled patients were classified into two groups based on the grade of acneiform rash caused by anti-EGFR antibody drugs: "Grade 1 and lower," and "Grade 2 and higher." The skin parameters were compared between these groups. The results showed that in the "Grade 2 and higher" group, TEWL in the face (at week 2 of administration), chest (baseline, weeks 2 and 6 of administration), and back (at week 2 of administration) were significantly higher than those in the "Grade 1 and lower" group. However, the two groups showed no significant differences in hydration or sebum levels at any time point.

CONCLUSION

TEWL can serve as a marker for acneiform rashes induced by anti-EGFR antibody drugs during cancer treatment.

Risk Evaluation of Proton Pump Inhibitors for Panitumumab-Related Hypomagnesemia in Patients with Metastatic Colorectal Cancer

Hypomagnesemia commonly occurs as a side effect of panitumumab treatment. In severe cases, temporary discontinuation or dose reduction of panitumumab may be necessary. Proton pump inhibitors (PPIs) are reportedly potential risk factors for hypomagnesemia. We conducted a multicenter study to assess the impact of PPIs on the risk of grade 3-4 hypomagnesemia in patients with metastatic colorectal cancer (mCRC) receiving panitumumab. We adjusted for potential bias using a propensity score-matched analysis and retrospectively reviewed the medical records of patients. Hypomagnesemia severity was graded according to the Common Terminology Criteria for Adverse Events, version 5.0. A total of 165 patients were enrolled in this study. The incidence of grade 3-4 hypomagnesemia was significantly higher in the PPI group than in the non-PPI group, both before (20.0% [30/60] vs. 8.0% [8/105], p = 0.026) and after propensity score matching (16.2% [6/37] vs. 0% [0/37], p = 0.025). In the propensity score-matched cohort, the risk of grade 3-4 hypomagnesemia was significantly higher in the PPI group (odds ratio, 2.19; 95% confidence interval, 1.69-2.84; p = 0.025). These findings suggest that concomitant use of PPIs significantly increases the risk of grade 3-4 hypomagnesemia in patients with mCRC receiving panitumumab. Therefore, close monitoring of these patients is imperative.

Anti-epidermal growth factor receptor targeted therapy-associated ulcerations

The well-studied role of epidermal growth factor receptor (EGFR) in metastatic colorectal cancer (mCRC) and non-small cell lung cancer (NSCLC) has enabled the development of drugs that target this molecule, including panitumumab for the former and osimertinib for the latter. Oral adverse events due to those agents are rarely described in the literature and their exact characterization is hampered by inadequate reporting and/or incorrect terminology used. We report two cases of panitumumab- and osimertinib-associated oral ulcerations with emphasis on their possible pathogenesis and optimal management.

Phase Ib/II Study of the Efficacy and Safety of Binimetinib (MEK162) Plus Panitumumab for Mutant or Wild-Type RAS Metastatic Colorectal Cancer

INTRODUCTION

Activating RAS gene mutations occur in approximately 55% of patients with metastatic colorectal cancer (mCRC) and are associated with poorer clinical outcomes due to epidermal growth factor receptor (EGFR) blockade resistance. Combined EGFR and mitogen-activated protein kinase (MEK) inhibition may extend response to EGFR inhibition and overcome acquired resistance. This phase Ib/II dose escalation trial evaluated the safety and activity of dual inhibition with binimetinib (MEK1/2 inhibitor) and panitumumab (EGFR inhibitor [EGFRi]) in patients with RAS mutant or BRAF wild type (WT)/RAS WT mCRC.

METHODS

Phase Ib dose escalation started with binimetinib 45 mg twice daily plus panitumumab 6 mg/kg administered every 2 weeks. In the phase II study, patients with measurable mCRC were enrolled into 4 groups based on previous anti-EGFR monoclonal antibody therapy and RAS mutational status.

RESULTS

No patients in the phase Ib portion (n = 10) had a response; 70% of patients had stable disease. In the phase II portion (n = 43), overall response rate (ORR, confirmed) was 2.3% with one partial response in the RAS WT group, DCR was 30.2%, and median progression-free survival was 1.8 months (95%CI, 1.6-3.3). All patients experienced ≥1 adverse event, with the most common being diarrhea (71.7%), vomiting (52.8%), nausea (50.9%), fatigue (49.1%), dermatitis acneiform (43.4%), and rash (41.5%). Most patients required treatment interruption or dose reduction due to difficulties tolerating treatment.

CONCLUSIONS

The combination of binimetinib and panitumumab had substantial toxicity and limited clinical activity for patients with mutant or WT RAS mCRC, independent of EGFRi treatment history (Trial registration: NCT01927341).

Sotorasib plus Panitumumab in Refractory Colorectal Cancer with Mutated KRAS G12C

BACKGROUND

KRAS G12C is a mutation that occurs in approximately 3 to 4% of patients with metastatic colorectal cancer. Monotherapy with KRAS G12C inhibitors has yielded only modest efficacy. Combining the KRAS G12C inhibitor sotorasib with panitumumab, an epidermal growth factor receptor (EGFR) inhibitor, may be an effective strategy.

METHODS

In this phase 3, multicenter, open-label, randomized trial, we assigned patients with chemorefractory metastatic colorectal cancer with mutated KRAS G12C who had not received previous treatment with a KRAS G12C inhibitor to receive sotorasib at a dose of 960 mg once daily plus panitumumab (53 patients), sotorasib at a dose of 240 mg once daily plus panitumumab (53 patients), or the investigator's choice of trifluridine-tipiracil or regorafenib (standard care; 54 patients). The primary end point was progression-free survival as assessed by blinded independent central review according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Key secondary end points were overall survival and objective response.

RESULTS

After a median follow-up of 7.8 months (range, 0.1 to 13.9), the median progression-free survival was 5.6 months (95% confidence interval [CI], 4.2 to 6.3) and 3.9 months (95% CI, 3.7 to 5.8) in the 960-mg sotorasib-panitumumab and 240-mg sotorasib-panitumumab groups, respectively, as compared with 2.2 months (95% CI, 1.9 to 3.9) in the standard-care group. The hazard ratio for disease progression or death in the 960-mg sotorasib-panitumumab group as compared with the standard-care group was 0.49 (95% CI, 0.30 to 0.80; P = 0.006), and the hazard ratio in the 240-mg sotorasib-panitumumab group was 0.58 (95% CI, 0.36 to 0.93; P = 0.03). Overall survival data are maturing. The objective response was 26.4% (95% CI, 15.3 to 40.3), 5.7% (95% CI, 1.2 to 15.7), and 0% (95% CI, 0.0 to 6.6) in the 960-mg sotorasib-panitumumab, 240-mg sotorasib-panitumumab, and standard-care groups, respectively. Treatment-related adverse events of grade 3 or higher occurred in 35.8%, 30.2%, and 43.1% of patients, respectively. Skin-related toxic effects and hypomagnesemia were the most common adverse events observed with sotorasib-panitumumab.

CONCLUSIONS

In this phase 3 trial of a KRAS G12C inhibitor plus an EGFR inhibitor in patients with chemorefractory metastatic colorectal cancer, both doses of sotorasib in combination with panitumumab resulted in longer progression-free survival than standard treatment. Toxic effects were as expected for either agent alone and resulted in few discontinuations of treatment. (Funded by Amgen; CodeBreaK 300 ClinicalTrials.gov number, NCT05198934.).

Panitumumab in combination with chemoradiotherapy for the treatment of locally-advanced anal canal carcinoma: Results of the FFCD 0904 phase II trial

BACKGROUND AND PURPOSE

Standard treatment of squamous cell carcinoma of the anus (SCCA)is 5-fluorouracil (5FU) and mitomycin C (MMC) based chemoradiotherapy (CRT). This phase II study (EudraCT: 2011-005436-26) assessed the tolerance and complete response (CR) rate at 8 weeks of panitumumab (Pmab) combined with MMC-5FU-based CRT.

METHODS

Patients with locally advanced tumors without metastases (T2 > 3 cm, T3-T4, or N + whatever T stage) were treated with IMRT up to 65 Gy and concomitant CT according to the doses defined by a previous phase I study (MMC: 10 mg/m2; 5FU: 400 mg/m2; Pmab: 3 mg/kg). The expected CR rate was 80%.

RESULTS

Forty-five patients (male: 9, female: 36; median age: 60.1 [41.5-81]) were enrolled in 15 French centers. The most common related grade 3-4 toxicities observed were digestive (51.1%), hematologic (lymphopenia: 73.4%; neutropenia: 11.1%), radiation dermatitis (13.3%), and asthenia (11.1%) with RT interruption in 14 patients. One patient died because of mesenteric ischemia during the CRT, possibly related to treatment. In ITT analysis, the CR rate at 8 weeks after CRT was 66.7% [90%CI: 53.4-78.2]. Median follow-up was 43.6 months [IC 95%: 38.61-47.01]. Overall survival, recurrence-free and colostomy-free survival at 3 years were 80% [95%CI: 65.1-89], 62.2% [IC95%: 46.5-74.6] and 68.8 % [IC95%: 53.1-80.2] respectively.

CONCLUSION

Panitumumab in combination with CRT for locally advanced SCCA failed to meet the expected CR rate and exhibited a poor tolerance. Furthermore, late RFS, CFS, and OS did not suggest any outcome improvement to justify further clinical trials.

CLINICALTRIALS

gov identifier: NCT01581840.

Risk factor analysis for anti-epidermal growth factor receptor monoclonal antibody-induced skin toxicities in real-world metastatic colorectal cancer treatment

PURPOSE

Anti-epidermal growth factor receptor (anti-EGFR) monoclonal antibodies are effective in treating RAS wild-type metastatic colorectal cancer (mCRC). However, their administration induces skin toxicity, markedly reducing patients' quality of life. This study is aimed at identifying the risk factors associated with anti-EGFR monoclonal antibody-induced skin toxicities.

METHODS

Patients with mCRC (n = 116) who received anti-EGFR monoclonal antibody treatment were retrospectively evaluated. Primary endpoint was evaluation of the risk factors for grade ≥ 2 overall skin toxicities during all the treatment periods. Furthermore, factors associated with each grade ≥ 2 skin symptoms were assessed.

RESULTS

Incidence of total grade ≥ 2 skin toxicity symptoms was 61.2%, and those of grade ≥ 2 rash, dry skin, fissures, and paronychia were 34.5%, 25.9%, 20.7%, and 25.0%, respectively. Multivariate logistic regression analyses revealed that liver metastasis was an independent risk factor for overall grade ≥ 2 skin toxicities (adjusted odds ratio [OR], 2.88; 95% confidence interval [CI], 1.22-6.78; P = 0.02) and prophylactic administration of antibiotics as a preventive factor (OR 0.10; 95%CI 0.01-0.91; P = 0.04). For grade ≥ 2 rash, prophylactic use of systemic antibiotics and topical steroid ointment was a preventive factor (OR 0.37; 95%CI 0.16-0.89; P = 0.03). Moreover, liver metastasis (OR 8.37; 95%CI 1.98-35.47; P = 0.004) and prophylactic administration of antibiotics (OR 0.15; 95%CI 0.03-0.76; P = 0.02) were significantly associated with grade ≥ 2 paronychia.

CONCLUSION

Liver metastasis was suggested to be a risk factor for the incidence of overall grade ≥ 2 skin toxicities; moreover, preemptive systemic antibiotic administration drastically decreased this risk during all periods of anti-EGFR treatment for mCRC.

Panitumumab vs Bevacizumab Added to Standard First-line Chemotherapy and Overall Survival Among Patients With RAS Wild-type, Left-Sided Metastatic Colorectal Cancer: A Randomized Clinical Trial

Importance

For patients with RAS wild-type metastatic colorectal cancer, adding anti-epidermal growth factor receptor (anti-EGFR) or anti-vascular endothelial growth factor (anti-VEGF) monoclonal antibodies to first-line doublet chemotherapy is routine, but the optimal targeted therapy has not been defined.

Objective

To evaluate the effect of adding panitumumab (an anti-EGFR monoclonal antibody) vs bevacizumab (an anti-VEGF monoclonal antibody) to standard first-line chemotherapy for treatment of RAS wild-type, left-sided, metastatic colorectal cancer.

Design, Setting, and Participants

Randomized, open-label, phase 3 clinical trial at 197 sites in Japan in May 2015-January 2022 among 823 patients with chemotherapy-naive RAS wild-type, unresectable metastatic colorectal cancer (final follow-up, January 14, 2022).

Interventions

Panitumumab (n = 411) or bevacizumab (n = 412) plus modified fluorouracil, l-leucovorin, and oxaliplatin (mFOLFOX6) every 14 days.

Main Outcomes and Measures

The primary end point, overall survival, was tested first in participants with left-sided tumors, then in the overall population. Secondary end points were progression-free survival, response rate, duration of response, and curative (defined as R0 status) resection rate.

Results

In the as-treated population (n = 802; median age, 66 years; 282 [35.2%] women), 604 (75.3%) had left-sided tumors. Median follow-up was 61 months. Median overall survival was 37.9 months with panitumumab vs 34.3 months with bevacizumab in participants with left-sided tumors (hazard ratio [HR] for death, 0.82; 95.798% CI, 0.68-0.99; P = .03) and 36.2 vs 31.3 months, respectively, in the overall population (HR, 0.84; 95% CI, 0.72-0.98; P = .03). Median progression-free survival for panitumumab vs bevacizumab was 13.1 vs 11.9 months, respectively, for those with left-sided tumors (HR, 1.00; 95% CI, 0.83-1.20) and 12.2 vs 11.4 months overall (HR, 1.05; 95% CI, 0.90-1.24). Response rates with panitumumab vs bevacizumab were 80.2% vs 68.6%, respectively, for left-sided tumors (difference, 11.2%; 95% CI, 4.4%-17.9%) and 74.9% vs 67.3% overall (difference, 7.7%; 95% CI, 1.5%-13.8%). Median duration of response with panitumumab vs bevacizumab was 13.1 vs 11.2 months for left-sided tumors (HR, 0.86; 95% CI, 0.70-1.10) and 11.9 vs 10.7 months overall (HR, 0.89; 95% CI, 0.74-1.06). Curative resection rates with panitumumab vs bevacizumab were 18.3% vs 11.6% for left-sided tumors; (difference, 6.6%; 95% CI, 1.0%-12.3%) and 16.5% vs 10.9% overall (difference, 5.6%; 95% CI, 1.0%-10.3%). Common treatment-emergent adverse events were acneiform rash (panitumumab: 74.8%; bevacizumab: 3.2%), peripheral sensory neuropathy (panitumumab: 70.8%; bevacizumab: 73.7%), and stomatitis (panitumumab: 61.6%; bevacizumab: 40.5%).

Conclusions and Relevance

Among patients with RAS wild-type metastatic colorectal cancer, adding panitumumab, compared with bevacizumab, to standard first-line chemotherapy significantly improved overall survival in those with left-sided tumors and in the overall population.

Trial Registration

ClinicalTrials.gov Identifier: NCT02394795.

Multicentre single-arm phase II trial evaluating the safety and effiCacy of Panitumumab and iRinOtecan in NeoRAS Wild-type mEtaStatic colorectal cancer patientS (C-PROWESS trial): study protocol

INTRODUCTION

A new concept of 'NeoRAS wild-type (WT)', which means conversion of RAS status from RAS mutant to RAS WT after treatment, has been reported. Previous observational and proof-of-concept studies have demonstrated the efficacy of epidermal growth factor receptor inhibitors in patients with NeoRAS WT metastatic colorectal cancer (mCRC). Moreover, posthoc biomarker analyses of these studies have suggested that not only the RAS status in the circulating tumour DNA (ctDNA) but also other gene mutational status may be useful as biomarkers of epidermal growth factor receptor inhibitors for NeoRAS WT mCRC.

METHODS AND ANALYSIS

This trial is a multicentre, single-arm, phase II trial to assess the efficacy and safety of panitumumab plus irinotecan therapy for patients with NeoRAS mCRC. The key eligibility criteria include RAS mutant mCRC initially proven in tumour tissue refractory or intolerant to fluoropyrimidine, oxaliplatin and irinotecan; RAS WT in ctDNA (defined as plasma mutant allele frequencies of all RAS ≤0.1%) within 28 days before enrolment and Eastern Cooperative Oncology Group performance status ≤2. The primary endpoint is the response rate. The target sample size is 30 patients. Biomarker analyses are planned to be performed using next-generation sequencing-based ctDNA analysis.

ETHICS AND DISSEMINATION

This study was approved by the certified review board of National Cancer Center Hospital. The main results of the trial will be presented in international meetings and in medical journals.

TRIAL REGISTRATION NUMBER

s031210565.

Hematochezia Due to Panitumumab-induced Colitis with Vitamin K Deficiency

Panitumumab, a fully human anti-epidermal growth factor receptor (EGFR) monoclonal antibody, has been shown to be useful in treating either advanced or recurrent KRAS/NRAS/BRAF wild-type colorectal cancer. We herein report the case of a 60-year-old man with short bowel syndrome who developed hematochezia due to panitumumab-induced colitis with vitamin K deficiency during third-line chemotherapy. The cause of vitamin K deficiency was the lack of intravenous vitamin K supplementation following a change from central venous nutrition to peripheral venous nutrition. We advise clinicians to carefully check for colitis and manage the infusions of chemotherapy patients with short bowel syndrome.

[Challenge of Skin Treatment Led by Nurses and Pharmacists for Advanced Colorectal Cancer Patients Treated with Anti-EGFR Antibodies]

Preemptive skin treatment led by nurses and pharmacists was started for patients with metastatic colorectal cancer (mCRC)who received anti-EGFR antibody treatment. Incidence of skin-related toxicities, amount of topical moisturizers used, and administered cycles of anti-EGFR antibody were retrospectively compared between a preemptive skin treatment group and a control group. Thirty-four mCRC patients before the introduction of preemptive skin treatment led by nurses and 23 mCRC patients treated with preemptive skin treatment led by nurses were evaluated. The incidence of 6- and 12- week Grade 2 or higher skin-related toxicity was 23.5% in the control group and 8.7% in the preemptive group(p=0.18), and 67.7% in the control group and 30.4% in the preemptive group(p=0.0076), respectively. Mean amounts of moisturizer used were both lower in the control group than in the preemptive group at both 6 weeks and 7-12 weeks(6 weeks; 275 g vs 550 g, p=0.036, 7-12 weeks; 575 g vs 1,175 g, p=0.013). However, the amount of topical steroid used was similar in both groups. Preemptive moisturizer skin treatment led by nurses and pharmacists may decrease the incidence of skin- related toxicity.

Effect of proton pump inhibitors on the development of hypomagnesemia induced by panitumumab

Panitumumab, a therapeutic agent for unresectable advanced/recurrent colorectal cancer, is a human IgG2 monoclonal antibody that binds to and inhibits the activity of the epidermal growth factor receptor (EGFR). The onset of hypomagnesemia is a known side effect of anti-EGFR inhibitors, including panitumumab, and it is thought that inhibition of reabsorption of Mg in renal tubules is one of the causes. In addition, recent reports have shown that long-term administration of proton pump inhibitors (PPIs) reduces serum magnesium levels. Therefore, in this study, 102 patients who received oral PPIs treated with panitumumab were classified into a PPI combination group and a PPI non-combination group, and the effect of PPIs on the development of grade 2 or higher hypomagnesemia was investigated. The incidence of hypomagnesemia in the PPI combination group (46.9%, 15/32) was higher than that in the PPI non-combination group (25.7%, 18/70). A comparison of the backgrounds of the two groups of patients showed a significant difference in serum albumin levels. PPI administration was significantly associated with panitumumab-induced hypomagnesemia development when adjusted for known risk factors, serum albumin level, renal function, and oral magnesium oxide tablets in Cox proportional hazards regression analysis (hazard ratio 2.09; 95% confidence interval 1.03-4.22; P =0.040). These results indicate that detailed monitoring of serum magnesium levels is recommended for patients treated with panitumumab and co-administration of PPIs.

Reducing Skin Toxicities from EGFR Inhibitors with Topical BRAF Inhibitor Therapy

Treatment of cancer with EGFR inhibitors is limited by on-target skin toxicities induced by inhibition of the MAPK pathway. BRAF inhibitors are known to paradoxically activate the MAPK downstream of EGFR, which we confirmed using human skin keratinocytes. We then conducted a phase I clinical trial testing the hypothesis that topical therapy with the BRAF inhibitor LUT014 could improve skin toxicities induced by EGFR inhibitors. Ten patients with metastatic colorectal cancer who had developed acneiform rash while being treated with cetuximab or panitumumab were enrolled in three cohorts. LUT014 was well tolerated, and there were no dose-limiting toxicities. The acneiform rash improved in the 6 patients who started with grade 2 rash in the low and intermediate cohorts. We conclude that topical LUT014 is safe and efficacious in improving rash from EGFR inhibitors, consistent with the mechanism of action inducting paradoxical MAPK activation. SIGNIFICANCE: BRAF inhibitor topical therapy could avoid dose reductions of EGFR inhibitors, locally treating the main dose-limiting skin toxicity of this class of agents.This article is highlighted in the In This Issue feature, p. 2113.

REMARRY and PURSUIT trials: liquid biopsy-guided rechallenge with anti-epidermal growth factor receptor (EGFR) therapy with panitumumab plus irinotecan for patients with plasma RAS wild-type metastatic colorectal cancer

BACKGROUND

Previous clinical trials have demonstrated the potential efficacy of rechallenge with anti- epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) for patients with RAS/BRAF V600E wild-type metastatic colorectal cancer (mCRC). Moreover, post hoc biomarker analyses of clinical trials has suggested that RAS status in circulating tumor DNA (ctDNA) has a high probability to select patients who could benefit from anti-EGFR mAb rechallenge.

METHODS

This trial is composed of 2 phases: a monitoring phase (REMARRY) and a trial phase (PURSUIT). A monitoring phase, the REMARRY study, aims to evaluate the dynamics of plasma RAS status during the subsequent treatments after refractory to anti-EGFR therapy in patients with mCRC with RAS/BRAF V600E wild-type tumors who have progressed after a response to previous anti-EGFR therapy, using a highly sensitive digital polymerase chain reaction OncoBEAM RAS CRC kit in a central laboratory (Sysmex, Japan). A trial phase, the PURSUIT trial, is a multicenter, single-arm phase II trial to assess the efficacy and safety of rechallenge therapy with panitumumab plus irinotecan in patients without RAS mutations in ctDNA (plasma RAS negative) in the REMARRY study. Key eligibility criteria of the PURSUIT trial include RAS/BRAF V600E wild-type mCRC in tumor tissue refractory or intolerant to fluoropyrimidine, oxaliplatin, and irinotecan; progression after complete or partial response to previous anti-EGFR therapy; plasma RAS negative (defined as plasma mutant allele frequencies [MAF] of all RAS ≤ 0.1%) within 28 days prior to enrollment; 4 months or more between the last administration of previous anti-EGFR mAb and the start of protocol treatment; and Eastern Cooperative Oncology Group (ECOG) Performance Status (PS) ≤ 1. The primary endpoint is the confirmed objective response rate (ORR). The target sample size of the PURSUIT trial is 50 patients. Biomarker analyses will be performed in parallel using the OncoBEAM RAS CRC kit and a next-generation sequencing-based ctDNA analysis (Guardant360).

DISCUSSION

Our trial aims to confirm the clinical benefit of anti-EGFR mAb rechallenge therapy in patients with plasma RAS negative. Moreover, through biomarker analyses, our trial will shed light on which patients would benefit from rechallenge in addition to being plasma RAS negative.

TRIAL REGISTRATION

The REMARRY study: UMIN, UMIN000036424 . Registered date: April 5, 2019. The PURSUIT trial: jRCT, jRCTs031190096 . Registered date: October 1, 2019.

Meta-analysis on the risk of fatal adverse events by bevacizumab, cetuximab, and panitumumab in 31 randomized trials including 25,000 patients with colorectal carcinoma

BACKGROUND

Targeted drugs including bevacizumab, cetuximab, and panitumumab have been widely used during the management of patients diagnosed with colorectal carcinoma, especially as palliative treatment. The present meta-analysis was performed to evaluate the fatal adverse events (FAEs) of targeted drugs including bevacizumab, cetuximab, and panitumumab in patients with colorectal cancer.

PATIENTS AND METHODS

Studies of prospective, randomized, and controlled feature from EMBASE, Medline, and Cochrane Library, which reported FAEs potentially associated with bevacizumab, cetuximab, and panitumumab were adopted. Clinical characteristics and FAEs were collected from the enrolled literatures, with the quality of which been evaluated. Pooled analysis of FAEs, caused by each agent as first line, second/further line, and adjuvant treatment were performed with relative risks (RRs) and their corresponding 95% confidence intervals (CIs) in software RevMan 5.3.

RESULTS

Thirty-one studies including 25,939 patients were brought into the final analysis. The RR and its 95% CI of the FAEs among all the agents including bevacizumab, cetuximab, and panitumumab was 1.07 (95% CI, 0.89-1.29; P = .50). The RRs and their 95% CIs of the FAEs as first line, second or further line, and adjuvant treatment related to bevacizumab were 0.91 (95% CI, 0.62-1.32; P = .61), 1.14 (95% CI, 0.57-2.28; P = .71), and 1.10 (95% CI, 0.67-1.79; P = .72). The RRs and their 95% CIs of the FAEs as first line, second or further line, and adjuvant treatment related to cetuximab were 1.02 (95% CI, 0.60-1.76; P = .93), 2.51 (95% CI, 0.49-12.88; P = .27), and 2.40 (95% CI, 1.00-5.77; P = .05). The RRs and their 95% CIs of the FAEs as first line, second or further line treatment related to panitumumab were 1.40 (95% CI, 0.89-2.18; P = .14) and 0.68 (95% CI, 0.43-1.09; P = .11), respectively.

CONCLUSIONS

The present meta-analysis did not show any significantly increased RR of FAEs belonging to bevacizumab, cetuximab, or panitumumab, whether as first line, second/further line, or adjuvant treatment among patients with colorectal carcinoma comparing to placebo or blank treatment.

Randomized, Double-Blind, Placebo-Controlled Phase Ⅱ Study on the Efficacy and Safety of Vitamin K1 Ointment for Cetuximab or Panitumumab-Induced Acneiform Eruptions-VIKTORIA Study

PURPOSE

Skin toxicities associated with anti-epidermal growth factor receptor(EGFR)antibodies, have a profound effect on the continuation of treatment. We assessed the efficacy and safety of vitamin K1(VK1)ointment for acneiform eruptions induced by anti-EGFR antibody treatment.

METHODS

The VK1 ointment was applied to one-half of an affected area and placebo ointment was applied to the other half twice a day for 8 weeks, with photography and clinical evaluation being performed every 2 weeks. The primary endpoint was the change of the VK1/placebo ratio for the number of acneiform eruptions counted by an independent dermatologist between the onset and end of the treatment period.

RESULTS

A total of 30 patients were enrolled. The mean VK1/placebo ratio for the number of acneiform eruptions between the onset and end of the treatment period was -0.158±0.680 and 0.146±0.575, respectively, which was not statistically significant(p=0.069). The mean number of acneiform eruptions at each treatment period at the VK1 and placebo application sites was gradually decreased according to the treatment period.

CONCLUSION

VK1 ointment was not effective against acneiform eruptions induced by treatment with cetuximab or panitumumab. Reassessment of the VK1 concentration in the ointment and the endpoint of skin lesions is required before designing further studies.

Current Recommendations and Novel Strategies for the Management of Skin Toxicities Related to Anti-EGFR Therapies in Patients with Metastatic Colorectal Cancer

The use of targeted therapies, when added to conventional chemotherapy, has significantly improved clinical outcomes and survival of cancer patients. While targeted therapies do not have the systemic adverse reactions of chemotherapy, they are associated with toxicities that can be severe and impair patient quality of life and adherence to anti-cancer treatment. Panitumumab and cetuximab, two monoclonal antibodies against epidermal growth factor receptor (EGFR), are recommended for the treatment of metastatic colorectal cancer (mCRC). The majority of patients with mCRC who are treated with anti-EGFR therapy develop skin toxicities, including papulopustular rash (the most common), xerosis, painful cracks and fissures on the palms and soles of the feet, paronychia, pruritus, and abnormal hair and eyelash growth; they are also more prone to skin infections. Given the involvement of EGFR in normal epidermis physiology, development and function, skin toxicities caused by anti-EGFR therapy are not unexpected. In recent years, recommendations have been formulated for the prevention and treatment of anti-EGFR therapy-related skin toxicities. Indeed, proper and timely management of these toxicities is important for ensuring uninterrupted anti-cancer treatment and optimal outcomes. Here, we review the current knowledge of anti-EGFR therapy-related skin toxicities and the latest recommendations for their management. We also present a treatment approach for papulopustular rash based on the combination of fusidic acid plus betamethasone in a lipid-enriched topical formulation. The effectiveness of this approach is documented by the presentation of five cases successfully treated in clinical practice for anti-EGFR therapy-related rash.

The role of miRNA -31-3p and miR-31-5p in the anti-EGFR treatment efficacy of wild-type K-RAS metastatic colorectal cancer. Is it really the next best thing in miRNAs?

Colorectal cancer (CRC) is one of the most common cancers worldwide with a high incidence and mortality. Although many treatment options are available in stage IV disease, the clinical outcome is still minimal. The primary treatment problem in metastatic colorectal cancer (mCRC) is early liver metastases that occur in more than 50% of patients. First-line treatment in metastatic colorectal cancer (mCRC) is a combination of chemotherapy plus targeted therapies like Cetuximab or Bevacizumab depending on K-RAS status. The decision of which regimen to choose is difficult because almost half of the patients don't receive second-line treatment due to complications or death. To avoid exposing non-responding patients to inefficient and harmful therapies new robust biomarkers are needed. Ongoing studies have demonstrated constantly that microRNAs (miRNAs) could become suitable biomarkers for screening and treatment response. In CRC, miR-31-3p and miR-31-5p dysregulation seems to have a particular role in evaluating treatment response from anti-EGFR therapy. In this review, we will present up to date information on the role of miRNA-31-3p and miR-31-5p in CRC with a particular focus in treatment response of metastatic K-RAS wild-type CRC treated with anti-EGFR molecules.

Impact of neutrophil-lymphocyte and platelet-lymphocyte ratio on antiEGFR and bevacizumab efficacy in metastatic colorectal cancer

PURPOSE

The purpose of this study was to determine the influence of the neutrophil-lymphocyte ratio (NLR) and the platelet-lymphocyte ratio (PLR) on antiEGFR and bevacizumab efficacy in metastatic colorectal cancer patients.

METHODS

All metastatic colorectal cancer patients who had received chemotherapy and biological agents as first-line treatment at Erciyes University Hospital were retrospectively reviewed. NLR and PLR were each divided into two groups, as high and low. The NLR high group was compared with the low group and the PLR high group was compared with the low group in patients in terms of progression-free survival (PFS) and overall survival (OS), separately. Cox regression and the Kaplan Meier method were used.

RESULTS

One hundred and thirty (58%) of the patients had received bevacizumab and 94 (42%) had received antiEGFR therapy (cetuximab or panitumumab). In the bevacizumab group, PFS was 9 months in the NLR high group and 11 months in the NLR low group (p=0.013). OS was 23 months in the NLR high group and 27 months in the NLR low group (p=0.734). There was no statistically significant OS difference in patients who had received antiEGFR therapy according to NLR. There was no statistically significant PFS difference in patients who received bevacizumab according to PLR. In the antiEGFR group, PFS was 9 months (95% CI, 8.07-13.55) in the PLR high group and 18 months (95% CI, 12.02-18.68) in the PLR low group, with statistically significant difference (p=0.040). There was no statistically significant OS difference in patients who had received antiEGFR therapy according to PLR.

CONCLUSIONS

NLR and PLR are important inflammatory markers. In patients who had received bevacizumab, PFS was longer in the NLR low group than in the high group. In patients who had received antiEGFR, PFS was longer in the PLR low group than in the high group.

Management of skin toxicities during panitumumab treatment in metastatic colorectal cancer

BACKGROUND

Anti-epidermal growth factor receptor therapy is associated with skin adverse events not previously reported with conventional chemotherapy. Prophylactic actions are recommended, but routine clinical management of these toxicities and their impact on quality of life remain unknown.

AIM

To assess the dermatological toxicities reported after panitumumab initiation, their impact on the quality of life and the clinical practices for their management.

METHODS

Patients included in this prospective multicenter observational study were over 18 years of age and began treatment with panitumumab for wild-type KRAS metastatic colorectal cancer. The incidence of dermatological toxicities, clinical practices for their management and impact on quality of life were recorded during a 6-mo follow-up.

RESULTS

Overall, 229 patients (males, 57.6%; mean age, 66.2 years) were included. At day 15, 59.3% of patients had dermatological toxicity; the rate peaked at month 2 (74.7%) and decreased at month 6 (46.5%). The most frequent dermatological toxicities were rash/acneiform rash, xerosis and skin cracks. At least one preventive treatment was administered to 65.9% of patients (oral antibiotics, 84.1%; emollients, 75.5%; both, 62.9%). The rates of patients who received at least one curative treatment peaked at month 2 (63.4%) and decreased at month 6 (44.8%). The impact of the dermatological toxicities on quality of life was limited as assessed with Dermatology Life Quality Index scores and inconvenience visual analogic scale score. The rates of topical corticosteroids administration and visits to specialists were low.

CONCLUSION

The rates of the different skin toxicities peaked at various times and were improved at the end of follow-up. Nevertheless, their clinical management could be optimized with a better adherence to current recommendations. The impact of skin toxicities on patient’s quality of life appeared to be limited.

FOLFOX alone or combined with rilotumumab or panitumumab as first-line treatment for patients with advanced gastroesophageal adenocarcinoma (PRODIGE 17-ACCORD 20-MEGA): a randomised, open-label, three-arm phase II trial

BACKGROUND

Epidermal growth factor receptor (EGFR) and hepatocyte growth factor (HGF)/mesenchymal-epithelial transition (MET) pathways, which promote tumour growth and proliferation, are often deregulated in advanced gastroesophageal adenocarcinomas. We assessed whether adding panitumumab (an EGFR inhibitor) or rilotumumab (a HGF inhibitor) to first-line fluoropyrimidine-based and platinum-based chemotherapy (modified oxaliplatin, leucovorin and fluorouracil [mFOLFOX6]) benefits to patients with advanced gastroesophageal adenocarcinoma.

PATIENTS AND METHODS

This phase II, open-label, randomised, three-arm study enrolled patients ≥18 years, with advanced gastroesophageal adenocarcinoma, Eastern Cooperative Oncology Group performance status 0-1 and no known HER2 overexpression. Patients were randomly assigned (1:1:1) mFOLFOX6 (oxaliplatin 85 mg/m², leucovorin 400 mg/m², 5-fluorouracil 400 mg/m² bolus then 2400 mg/m² over 46 h) alone or combined with panitumumab (6 mg/kg) or rilotumumab (10 mg/kg) every 2 weeks until limiting toxicity, patient's refusal or disease progression. The primary end-point was the 4-month progression-free survival (PFS) rate. Secondary end-points included overall survival (OS) and tolerance.

RESULTS

The study enrolled 162 patients in 29 French centres. The median follow-up was 23.6 months (interquartile range = 16.4-29.0). The 4-month PFS rate was 71% (95% confidence interval [CI] = 57-82) with chemotherapy alone, 57% (95% CI = 42-71) combined with panitumumab and 61% (95% CI = 47-74) combined with rilotumumab. Median OS was 13.1 months (95% CI = 8.7-16.9) with chemotherapy alone, 8.3 months (95% CI = 6.2-13.2) combined with panitumumab and 11.5 months (95% CI = 7.9-17.1) combined with rilotumumab. Adverse events grade ≥III occurred less frequently with chemotherapy alone (62%) than with panitumumab (83%) and rilotumumab (89%).

CONCLUSIONS

We found no benefit in adding panitumumab or rilotumumab to mFOLFOX6 first-line chemotherapy to treat advanced gastroesophageal adenocarcinoma patients.

TRIAL REGISTRATION

European Clinical Trials Database, number 2009-012797-12.

Prospective Observational Cohort Study to Describe the Use of Panitumumab in Combination with Chemotherapy in Real-World Clinical Practice for Patients with Wild-Type RAS mCRC

INTRODUCTION

This study aimed to better understand panitumumab use in real-life clinical practice in first- and second-line treatment of metastatic colorectal cancer in five European countries.

METHODS

This is a combined analysis of two observational, non-interventional prospective cohort studies, one of which was conducted in Germany and France, the other in Bulgaria, Czech Republic, and Hungary. The studies observed patients with wild-type [Kirsten] rat sarcoma viral oncogene homolog ([K]RAS/RAS) metastatic colorectal cancer (mCRC), who had been treated with panitumumab in combination with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) in the first line or with panitumumab combined with fluorouracil, leucovorin, and irinotecan (FOLFIRI) in the second line following fluoropyrimidine-based chemotherapy. The planned duration of observation was 12 months from the first dose of panitumumab.

RESULTS

A total of 332 patients treated with panitumumab + FOLFOX in the first line and 94 patients treated with panitumumab + FOLFIRI in the second line were analyzed. The median number of panitumumab infusions was 10.0 in first-line FOLFOX patients and 11.5 in second-line FOLFIRI patients; the median duration of panitumumab exposure was 5.7 and 6.9 months, respectively. The unadjusted overall response rate (complete or partial response) in patients with available post-baseline response assessment (n = 290) was 51.7% in first-line FOLFOX and 44.9% in second-line FOLFIRI patients. In the first-line setting, resectability was achieved in 9.3%. Reported hospitalizations were mostly cancer-related visits such as scheduled anticancer treatment administrations, tumor assessment visits, or interventions. The majority of adverse drug reactions were skin disorders, with 75.3% in first-line FOLFOX patients and 72.3% in second-line FOLFIRI patients.

CONCLUSION

Overall, the study results show that treatment patterns, clinical efficacy, and the safety profile of panitumumab in routine clinical practice were comparable to those in randomized controlled trials. The relatively low skin toxicity rate could be attributed to increasing experience in managing panitumumab-associated rash and some degree of underreporting.

FUNDING

Amgen.

Topical doxycycline foam 4% for prophylactic management of epidermal growth factor receptor inhibitor skin toxicity: an exploratory phase 2, randomized, double-blind clinical study

PURPOSE

Acneiform rash, a common toxicity of epidermal growth factor receptor inhibitors (EGFRIs), can cause patient discomfort, warranting changes in treatment. This study investigated the safety, tolerability, and efficacy of a novel doxycycline foam, FDX104 4%, for managing EGFRI-related skin toxicity.

METHODS

This was an exploratory phase 2, randomized, double-blind, placebo-controlled study. Subjects had metastatic colorectal cancer and were being treated with either cetuximab or panitumumab plus chemotherapy. Treatment (twice-daily topical FDX104 4% on one side of the face and vehicle foam on the other for 5 weeks) was initiated 7 ± 3 days prior to EGFRI therapy. Rash severity, safety, and tolerability were evaluated at 2 and 4 weeks after EGFRI start.

RESULTS

The mean maximal rash grade was lower with FDX104 4% vs vehicle, and fewer subjects developed moderate-to-severe (grades 2-3) rash. On the Global Severity Score scale, a statistically significant difference favored FDX104 4% over vehicle (P = .047). Adverse events (AEs) (n = 68) occurred in 20 subjects; most were mild or moderate. The most common AEs were oral mucositis, nausea, and vomiting, common to chemotherapy and EGFRI treatment. Study-drug-related AEs were experienced by five subjects and consisted of mild, local skin reactions. No study-drug-related systemic side effects were reported.

CONCLUSION

Twice-daily, topical administration of FDX104 4% as an adjunct to either cetuximab or panitumumab was safe and well tolerated, and appeared to prevent the onset of rash, especially severe rash. CLINICALTRIALS.

GOV IDENTIFIER

Trial Registration NCT02239731.

[Retrospective Investigation of the Risk Factors for Severity in Panitumumab-Induced Hypomagnesemia]

Hypomagnesemia caused by panitumumab can often lead to severe adverse effects, such as arrhythmia. However, the risk factors are still controversial. To clarify the risk factors and time to onset of panitumumab-induced hypomagnesemia, we retrospectively investigated the records of 30 patients who had received panitumumab. They were divided into Grade B2 hypomagnesemia and non-Grade B2 hypomagnesemia groups, according to their serum magnesium levels, and we compared patients' backgrounds, laboratory values, and concomitant drugs between the 2 groups. Univariate analysis revealed that hypocalcemia and non-administration of an oral magnesium preparation were significantly associated with Grade B2 hypomagnesemia induced by panitumumab. Incipient grade 1 hypocalcemia was observed after incipient Grade 1 hypomagnesemia in both groups. The occurrence of these complications was significant in the Grade B2 hypomagnesemia group. Thereafter, in all patients of the Grade B2 hypomagnesemia group that exhibited both complications, hypomagnesemia developed to Grade 2 or higher. The development of Grade 3 and Grade 4 hypomagnesemia without the development of Grade 2 hypomagnesemia was observed in 2 patients each. Thus, aggravation of hypomagnesemia can be expected upon the administration of panitumumab, and therefore, not only serum magnesium levels, but also serum calcium levels need to be monitored.

Phase II Study of Panitumumab in RAS Wild-Type Metastatic Adenocarcinoma of Small Bowel or Ampulla of Vater

Lessons Learned.

Panitumumab has no clinical activity in metastatic RAS wild‐type small bowel adenocarcinoma (SBA) and ampullary adenocarcinoma (AAC), possibly due to the foregut and midgut derivation of small bowel and ampulla.

These results, along with findings from genomic characterization of SBA, suggest that SBA represents a unique intestinal malignancy and treatments should not be habitually extrapolated from colorectal cancer.

Further studies evaluating the benefit of targeted therapies exclusively in SBA and AAC are warranted.

Background.

Given the benefit of epidermal growth factor receptor (EGFR) monoclonal antibodies in colorectal cancer (CRC), we sought to evaluate the efficacy of panitumumab in metastatic RAS wild‐type small bowel adenocarcinoma (SBA) and ampullary adenocarcinoma (AAC).

Methods.

We conducted a single‐center, open‐label, single‐arm, Bayesian phase II trial. The primary objective was response rate (RR). Panitumumab was administered at a dose of 6 mg/kg intravenously (IV) every 14 days.

Results.

Nine patients (male/female 7:2, median age: 61 years [range: 40–74], Eastern Cooperative Oncology Group [ECOG] performance status 0/1: 2/7) were enrolled from September 2013 to October 2015. One patient had AAC (pancreaticobiliary subtype) and eight patients had SBA (three duodenal, five jejunal/ileal). Acneiform rash was the most common toxicity. The study was stopped early due to futility with no responses, stable disease (SD) in two patients, and progression of disease (PD) in seven patients. Median progression‐free survival (PFS) and overall survival (OS) were 2.4 and 5.7 months, respectively. No patients had extended RAS mutations (exons 2/3/4), but two patients had BRAF G469A and one patient had PIK3CA H1074R mutations.

Conclusion.

Panitumumab had no clinically meaningful activity in patients with metastatic RAS wild‐type SBA and AAC. Our findings may relate to the primarily midgut and foregut derivation of the small bowel and ampulla.