Efficacy of Metformin in Patients With Breast Cancer Receiving Chemotherapy or Endocrine Therapy: Systematic Review and Meta-analysis.

BACKGROUND: Previous studies have suggested that metformin might improve survival outcomes in patients with breast cancer. However, findings on the efficacy of metformin with chemotherapy or endocrine therapy are inconsistent. OBJECTIVE: To clarify the efficacy of metformin with chemotherapy or endocrine therapy in breast cancer patients according to the treatment setting, including neoadjuvant, adjuvant, and metastasis/recurrence. METHODS: We systematically searched for randomized controlled trials (RCTs) in MEDLINE, CENTRAL, and EMBASE from inception through July 2020. Overall survival (OS), progression-free survival (PFS), and hypoglycemia rate were the primary outcomes. Secondary outcomes included severe adverse events (SAEs) and relapse-free survival. We used the Grading of Recommendations Assessment, Development, and Evaluation approach and performed a meta-analysis to evaluate the efficacy and safety of metformin with chemotherapy and endocrine therapy in patients with breast cancer. RESULTS: Our systematic review included 412 participants from 5 trials. Metformin showed little to no difference in OS (hazard ratio [HR] = 1.13; 95% CI = 0.71-1.81; certainty of evidence [COE], moderate) and PFS (HR = 1.14; 95% CI = 0.86-1.50; COE, moderate) in patients with metastasis/recurrence. The evidence was very uncertain about the effect of metformin on survival outcomes in patients who received metformin with neoadjuvant or adjuvant treatment. Metformin showed little to no difference in hypoglycemia and SAEs. CONCLUSION AND RELEVANCE: Metformin should be discouraged routinely in nondiabetic patients with metastatic/recurrent breast cancer. Further RCTs are needed to verify whether metformin with chemotherapy or endocrine therapy results in significant clinical benefits in the neoadjuvant or adjuvant setting.

Quality of clinical practice guidelines in Japan remains low: A cross-sectional meta-epidemiological study.

OBJECTIVES: We aimed to evaluate the characteristics, quality, and related factors of the Japanese Clinical Practice Guidelines (CPGs) published in recent years. STUDY DESIGN AND SETTING: In this cross-sectional, meta-epidemiological study, we conducted a Google search for CPGs published by 30 Japanese medical societies that are the basis for training specialties between 2018 and 2019. We used the Appraisal of Guidelines for Research & Evaluation II (AGREE II) tool and the Reporting Items for practice Guidelines in HealThcare (RIGHT) statement to evaluate the quality. RESULTS: We included 53 systematic review-based CPGs. The median score was 0.54 (IQR, 0.38-0.62) for Stakeholder involvement, 0.57 (IQR, 0.51-0.66) in Rigor of development, 0.33 (IQR 0.21-0.46) in Applicability, and 0.63 (IQR 0.46-0.73) in Editorial independence. The number of guideline developers/clinical question ratio (odds ratio [OR]: 4.14, 95% confidence interval [CI]: 1.97, 8.70) and the adopted guideline development methods (OR: 3.69, 95% CI: 1.14, 12.0) were significantly related to the Rigor of development. CONCLUSION: The quality of Japanese CPGs published in recent years remains low. Our study suggests that increasing contributors and adopting the latest guideline development methods at the beginning of the project may improve the quality of the Japanese CPGs.

Meta-analysis of the efficacies of amiodarone and nifekalant in shock-resistant ventricular fibrillation and pulseless ventricular tachycardia.

Amiodarone (AMD) and nifekalant (NIF) are used in the treatment of ventricular fibrillation or tachycardia; however, only few studies have been conducted on their efficacies. Therefore, a meta-analysis was conducted. Relevant sources were identified from PubMed, Cochrane Central Register of Controlled Trials, and Igaku Chuo Zasshi. The outcomes were short-term and long-term survival in patients with shock-resistant ventricular fibrillation /pulseless ventricular tachycardia. Thirty-three studies were analysed. The results showed that, compared to the control treatment, AMD did not improve short-term survival (odds ratio (OR): 1.25, 95% confidence interval (CI): 0.91-1.71) or long-term survival (OR: 1.00, 95% CI: 0.63-1.57). However, compared to the control treatment, NIF significantly improved short-term survival (OR: 3.23, 95% CI: 2.21-4.72) and long-term survival (OR: 1.88, 95% CI: 1.36-2.59). No significant difference was observed in short-term survival (OR: 0.85, 95% CI: 0.63-1.15) or long-term survival (OR: 1.25, 95% CI: 0.67-2.31) between AMD- and NIF-treated patients. The results suggest that NIF is beneficial for short-term and long-term survival in shock-resistant ventricular fibrillation/pulseless ventricular tachycardia; however, the efficacy of AMD in either outcome is not clear.

Triplet therapy with afatinib, cetuximab, and bevacizumab induces deep remission in lung cancer cells harboring EGFR T790M in vivo.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have changed the treatment strategy for EGFR-mutant lung cancers; however, resistance usually occurs due to a secondary mutation, T790M, in EGFR. Combination therapy using afatinib and cetuximab has had good results in lung tumors harboring EGFRT790M mutations in clinical trials. The effect of bevacizumab, an antivascular endothelial growth factor (VEGF) antibody, combined with EGFR-TKIs has also been investigated. We hypothesized that the dose of afatinib and cetuximab could be reduced by combination with bevacizumab and that the triplet therapy may result in better tumor inhibition with tolerable toxicity. Using a xenograft mouse model with H1975-harboring EGFRL858R+T790M and RPC-9-harboring EGFR19DEL+T790M , we tested the efficacy of the triplet therapy with a modified dose of afatinib, cetuximab, and bevacizumab, and compared this therapy to single and double therapies. Triplet therapy with afatinib, cetuximab, and bevacizumab induced pathological complete remission in xenograft tumors with H1975 and RPC-9 cells versus tumors treated with single or double therapies. We saw no body weight loss in the mice. The triple therapy induced a significant reduction in CD31-positive vascular endothelial cells and increased cleaved caspase-3-positive cells in the tumors. This suggests that one mechanism underlying the deep remission could be suppression of neovascularization and induction of apoptosis by intensive inhibition of driver oncoproteins and VEGF. These results highlight the potential of afatinib, cetuximab, and bevacizumab to induce deep remission in tumors harboring EGFRT790M mutations. Therefore, clinical trials of this combination therapy are warranted.

Ganglioside inserted into PEGylated liposome attenuates anti-PEG immunity.

Despite the clinical introduction of a vast number of polyethylene glycol (PEG)-conjugated therapeutics, conjugated PEG is also known for an unfortunate inclination toward immunogenicity. Immunogenicity of PEG, manifested by the robust production of anti-PEG IgM, is known to compromise the therapeutic efficacy and/or reduce the tolerance of PEGylated therapeutics. In the present study, we inserted ganglioside into the membrane of PEGylated liposome (PL) to prepare ganglioside-modified PEGylated liposomes (G-PL), and investigated its efficacy in attenuating the anti-PEG IgM response against PL. A single intravenous injection of G-PL significantly attenuated the anti-PEG IgM production, compared with that of naïve PL. In addition, pretreatment with G-PL substantially alleviated the anti-PEG IgM response elicited by a subsequent dose of PL, presumably via inducing B cell tolerance, and as a consequence, this modification abrogated/attenuated the incidence of the rapid clearance of subsequently administrated PL. These results indicate that incorporating gangliosides in PEGylated liposome membrane not only prevents the immunogenicity of PEG but also induces the tolerance of B cells to subsequent doses of the immunogenic PL. Consequently, liposomal membrane modification with ganglioside might represent a promising approach to attenuating the immunogenicity of PEGylated liposomes while preserving their therapeutic efficacy, particularly upon repeated administration.

Alternate-day Treatment with Crizotinib for Drug-induced Esophagitis and Liver Damage in a Patient with EML4-ALK Fusion Gene-positive Lung Adenocarcinoma.

A 44-year-old woman who was diagnosed with anaplastic lymphoma kinase-positive lung adenocarcinoma developed brain metastases, multiple spinal metastases and meningeal dissemination. Crizotinib was administered after the failure of first-line chemotherapy. Esophagitis and liver damage were induced by the twice-daily administration of crizotinib at 250 mg and 200 mg, respectively. The alternate-day administration of crizotinib (250 mg, twice daily) was able to control disease progression without any adverse effects for several months. We evaluated the relationship between the serum concentration of crizotinib and the development of esophagitis and liver damage. The alternate-day administration of crizotinib is one of the strategies for managing the severe toxicity of crizotinib.

Correlation of plasma crizotinib trough concentration with adverse events in patients with anaplastic lymphoma kinase positive non-small-cell lung cancer.

BACKGROUND: Crizotinib, an ATP-competitive receptor tyrosine kinase inhibitor of both anaplastic lymphoma kinase (ALK) and the hepatocyte growth factor receptor, commonly causes several adverse events (AEs). The clinical utility of measuring the plasma concentration of crizotinib in patients with non-small-cell lung cancer (NSCLC) has not been fully elucidated. The aim of this study was to evaluate the variability in the crizotinib trough concentration and its relationship with the occurrence of AEs in NSCLC patients. FINDINGS: Plasma samples were collected from 9 ALK fusion gene-positive NSCLC Japanese patients at day 14 after the first administration of crizotinib. We assessed crizotinib-induced AEs on days 7, 14, 21, and 28. The crizotinib trough concentration on day 14 ranged from 243.5 to 847.8 ng/mL, and all of the patients achieved stable disease based on assessment of the tumor response on day 28. The cumulative number of AEs on day 28 in the higher trough concentration group was approximately 3-fold greater than that in the lower trough concentration group. AEs of grade 3 or 4 were observed only in patients in the higher trough concentration group. CONCLUSIONS: The occurrence of several AEs may correlate with the increase in the crizotinib trough concentration. Monitoring of the crizotinib trough concentration could predict the risk of development of several AEs and provide guidance for determining the optimal dose of crizotinib.