In this single-group, phase 2 study, the use of trastuzumab deruxtecan resulted in a response in 60% of women with HER2-positive advanced breast cancer who had received a median of six previous lines ...of therapy. The drug was associated with myelosuppression and gastrointestinal toxicity; interstitial lung disease was reported in 13.6% of the patients.
Therapies targeted to human epidermal growth factor receptor 2 (HER2) have proven effective against tumors positive for HER2 amplification, but there is an unmet clinical need for the treatment of ...tumors that express HER2 protein in the absence of HER2 amplification. fam‐ trastuzumab deruxtecan (DS‐8201a) is a novel antibody–drug conjugate composed of the anti‐HER2 antibody and the topoisomerase I inhibitor, an exatecan derivative. It has shown efficacy against tumors that express HER2 and is currently under evaluation in clinical trials. We here show that the antitumor activity of fam‐ trastuzumab deruxtecan is dependent on the expression level of HER2 protein in colorectal cancer (CRC) cell lines negative for HER2 amplification. We established isogenic CRC cell lines that express various levels of HER2 protein in the absence of HER2 amplification, and we found that cells that express HER2 at a high level were sensitive to fam‐ trastuzumab deruxtecan but not to conventional HER2‐targeted therapies. Furthermore, fam‐ trastuzumab deruxtecan manifested a bystander killing effect both in vitro and in vivo, with cells essentially negative for HER2 expression also being killed in the presence of HER2‐expressing cells, an effect that has the potential to overcome heterogeneity of HER2 expression in CRC tumors. Our results thus suggest that fam‐ trastuzumab deruxtecan warrants further study as a potential treatment for CRC tumors that express HER2 protein in the absence of HER2 amplification.
What's new?
HER2‐targeted therapies have proven effective against tumors positive for HER2 amplification, but there is an unmet clinical need for tumors that express HER2 in the absence of HER2 amplification. fam‐ trastuzumab deruxtecan (DS‐8201a) is a novel antibody‐drug conjugate composed of the anti‐HER2 antibody and the topoisomerase I inhibitor. Here, DS‐8201a showed efficacy on colorectal cancer (CRC) cell lines that express HER2 in the absence of HER2 amplification. Furthermore, fam‐ trastuzumab deruxtecan exhibited a bystander killing effect in co‐culture models of HER2‐expressing cells and HER2‐negative cells. The results may offer a new treatment option against CRC according to HER2 expression levels.
The efficacy of programmed cell death–1 (PD‐1) blockade in patients with non–small cell lung cancer (NSCLC) positive for epidermal growth factor receptor (EGFR) gene mutations has been found to be ...limited, but the underlying mechanisms for this poor response have remained obscure. Given that the recognition by T cells of tumor antigens presented by major histocompatibility complex class I (MHC‐I) molecules is essential for an antitumor immune response, we examined the effects of EGFR tyrosine kinase inhibitors (TKIs) on MHC‐I expression in NSCLC cell lines. Appropriate EGFR‐TKIs increased MHC‐I expression at the mRNA and cell surface protein levels in NSCLC cells positive for EGFR mutations including those with the T790M secondary mutation. Trametinib, an inhibitor of the extracellular signal–regulated kinase (ERK) kinase MEK, also increased MHC‐I expression, whereas the phosphatidylinositol 3‐kinase (PI3K) inhibitor buparlisib did not, suggesting that the MEK‐ERK pathway mediates the down‐regulation of MHC‐I expression in response to EGFR activation. Immunohistochemical analysis of EGFR‐mutated NSCLC specimens obtained before and after EGFR‐TKI treatment also revealed down‐regulation of phosphorylated forms of EGFR and ERK in association with up‐regulation of MHC‐I, an increased number of infiltrating CD8+ T cells, and increased PD‐1 ligand 1 expression after such treatment. Our results thus suggest that mutational activation of EGFR inhibits MHC‐I expression through the MEK‐ERK pathway in NSCLC and thereby contributes to the poor response of such tumors to immunotherapy. Further studies are warranted to evaluate the relation between EGFR‐MEK‐ERK signaling in and the immune response to EGFR‐mutated NSCLC.
Mutational activation of EGFR inhibits MHC‐I expression through the MEK‐ERK pathway in NSCLC and thereby may contribute to the poor response of such tumors to immunotherapy.
Summary Background Patients with non-small-cell lung cancer harbouring mutations in the epidermal growth factor receptor ( EGFR ) gene respond well to the EGFR-specific tyrosine kinase inhibitor ...gefitinib. However, whether gefitinib is better than standard platinum doublet chemotherapy in patients selected by EGFR mutation is uncertain. Methods We did an open label, phase 3 study (WJTOG3405) with recruitment between March 31, 2006, and June 22, 2009, at 36 centres in Japan. 177 chemotherapy-naive patients aged 75 years or younger and diagnosed with stage IIIB/IV non-small-cell lung cancer or postoperative recurrence harbouring EGFR mutations (either the exon 19 deletion or L858R point mutation) were randomly assigned, using a minimisation technique, to receive either gefitinib (250 mg/day orally; n=88) or cisplatin (80 mg/m2 , intravenously) plus docetaxel (60 mg/m2 , intravenously; n=89), administered every 21 days for three to six cycles. The primary endpoint was progression-free survival. Survival analysis was done with the modified intention-to-treat population. This study is registered with UMIN (University Hospital Medical Information Network in Japan) , number 000000539. Findings Five patients were excluded (two patients were found to have thyroid and colon cancer after randomisation, one patient had an exon 18 mutation, one patient had insufficient consent, and one patient showed acute allergic reaction to docetaxel). Thus, 172 patients (86 in each group) were included in the survival analyses. The gefitinib group had significantly longer progression-free survival compared with the cisplatin plus docetaxel goup, with a median progression-free survival time of 9·2 months (95% CI 8·0–13·9) versus 6·3 months (5·8–7·8; HR 0·489, 95% CI 0·336–0·710, log-rank p<0·0001). Myelosuppression, alopecia, and fatigue were more frequent in the cisplatin plus docetaxel group, but skin toxicity, liver dysfunction, and diarrhoea were more frequent in the gefitinib group. Two patients in the gefitinib group developed interstitial lung disease (incidence 2·3%), one of whom died. Interpretation Patients with lung cancer who are selected by EGFR mutations have longer progression-free survival if they are treated with gefitinib than if they are treated with cisplatin plus docetaxel. Funding West Japan Oncology Group (WJOG): a non-profit organisation supported by unrestricted donations from several pharmaceutical companies.
Purpose
We present the English version of The Japanese Breast Cancer Society (JBCS) Clinical Practice Guidelines for systemic treatment of breast cancer, 2018 edition.
Methods
The JBCS formed a task ...force to update the JBCS Clinical Practice Guidelines, 2015 edition, according to Minds Handbook for Clinical Practice Guideline Development 2014. First, we set multiple outcomes for each clinical question (CQ). Next, quantitative or qualitative systematic review was conducted for each of the multiple outcomes, and the strength of recommendation for the CQ was taken into consideration during meetings, with the aim of finding a balance between benefit and harm. Finalized recommendations from each session were confirmed through discussion and voting at the recommendation decision meeting.
Results
The recommendations, the strength of recommendation and the strength of evidence were determined based on systemic literature reviews and the meta-analyses for each CQ.
Conclusion
The JBCS updated the Clinical Practice Guidelines for systemic treatment of breast cancer.
BACKGROUND
Fosnetupitant (FosNTP), an intravenous neurokinin 1 receptor antagonist, demonstrated a favorable safety profile with a potentially low risk of injection site reactions (ISRs) and ...promising antiemetic efficacy in patients receiving cisplatin‐based highly emetogenic chemotherapy in a previous phase 2 study. We conducted a randomized, double‐blind safety study to evaluate the safety profile of FosNTP, including ISRs, in patients receiving doxorubicin‐cyclophosphamide or epirubicin‐cyclophosphamide (AC/EC) chemotherapy.
METHODS
Patients scheduled to receive AC/EC were randomized 1:1 to receive 235 mg of FosNTP or 150 mg of fosaprepitant (FosAPR), both in combination with 0.75 mg of intravenous palonosetron and 9.9 mg of dexamethasone on day 1. The stratification factors were age category (<55 vs ≥55 years) and study site. The primary end point was the incidence of treatment‐related adverse events (TRAEs) with FosNTP.
RESULTS
Overall, 102 patients were randomized to FosNTP (n = 52) or FosAPR (n = 50), and all were treated with the study drug and evaluated for safety. The primary end point, the incidence of TRAEs, was similar with FosNTP (21.2%; 95% confidence interval CI, 11.1%‐34.7%) and FosAPR (22.0%; 95% CI, 11.5%‐36.0%), with any‐cause ISRs observed in 5.8% and 26.0% of patients, respectively, and treatment‐related ISRs observed in 0% and 10.0%, respectively. The overall (0‐120 hour) complete response (defined as no emetic event and no rescue medication) rate, standardized by age category in the full analysis set, was 45.9% (23 of 51 patients) with FosNTP and 51.3% (25 of 49 patients) with FosAPR.
CONCLUSIONS
FosNTP demonstrated a favorable safety profile with a very low risk of ISRs in the AC/EC setting.
Fosnetupitant shows a favorable safety profile in patients receiving doxorubicin‐cyclophosphamide or epirubicin‐cyclophosphamide chemotherapy. As an intravenous neurokinin 1 receptor antagonist with a low risk of causing injection site reactions, fosnetupitant may be used for protecting patients with cancer from experiencing chemotherapy‐induced nausea and vomiting.
The critical T790M mutation in
, which mediates resistance to first- and second-generation EGFR tyrosine kinase inhibitors (TKI; gefitinib, erlotinib, and afatinib), has facilitated the development ...of third-generation mutation-selective EGFR TKIs (rociletinib and osimertinib). We previously reported heterogeneous afatinib-resistant mechanisms, including emergence of T790M-
, and responses to third-generation EGFR TKIs. Here, we used afatinib-resistant lung adenocarcinoma cells AfaR (formerly AFR3) cells, carrying exon 19 deletion/T790M in
To identify the novel resistance mechanisms in post-afatinib treatment, RocR1/RocR2 and OsiR1/OsiR2 cells were established using increasing concentrations of rociletinib and osimertinib, respectively. Attenuation of exon 19 deletion and T790M was confirmed in both rociletinib-resistant cells; in addition,
and
amplification was observed in RocR1 and RocR2, respectively. Significant
amplification was observed in the osimertinib-resistant cell lines, indicating a linear and reversible increase with increased osimertinib concentrations in OsiR1 and OsiR2 cells. OsiR1 cells maintained osimertinib resistance with
amplification after osimertinib withdrawal for 2 months. OsiR2 cells exhibited KRAS attenuation, and osimertinib sensitivity was entirely recovered. Phospho-EGFR (Y1068) and growth factor receptor-bound protein 2 (GRB2)/son of sevenless homolog 1 (SOS1) complex was found to mediate osimertinib resistance in OsiR1 cells with sustained KRAS activation. After 2 months of osimertinib withdrawal, this complex was dissociated, and the EGFR signal, but not the GRB2/SOS1 signal, was activated. Concomitant inhibition of MAPK kinase and EGFR could overcome osimertinib resistance. Thus, we identified a heterogeneous acquired resistance mechanism for third-generation EGFR TKIs, providing insights into the development of novel treatment strategies.
Preclinical models revealed potential synergistic effects of programmed cell death-1 inhibitors and anti-vascular endothelial growth factor (VEGF) antibodies. Therefore, we investigated the use of ...nivolumab, bevacizumab, and paclitaxel triple therapy for metastatic breast cancer.
This phase 2, multicentre, single-arm study (NEWBEAT) investigated the safety and efficacy of first-line nivolumab, paclitaxel, and bevacizumab in patients with human epidermal growth factor receptor 2-negative metastatic breast cancer, regardless of programmed cell death-ligand 1 expression. The primary end-point was objective response rate. Key secondary end-points included progression-free survival, overall survival, and toxicities. A biomarker study evaluated tumour programmed cell death-ligand 1 expression and serum VEGF-A levels.
Between February 2018 and October 2018, 57 patients were enrolled. An objective response rate was seen in 39/56 patients (70%, 95% confidence interval CI: 55.9–81.2%), meeting the primary end-point. The objective response rate was 74% in patients with hormone receptor-positive breast cancer versus 59% in patients with triple-negative breast cancer. The median progression-free survival and overall survival were 14.0 (95% CI 11.0–16.3) and 32.5 (95% CI 26.0–not evaluable) months, respectively (median follow-up: 29.5 months). Grade 3/4 adverse drug reactions occurred in 33 of 57 patients (58%). There were no grade 5 adverse events. Immune-related adverse events occurred in 43 of 57 patients (75%), with grade 3/4 events in eight patients (14%). Biomarker analysis showed that tumour programmed cell death-ligand 1 expression was not correlated with the efficacy of triple therapy. Efficacy outcomes were similar between the serum VEGF-high and VEGF-low groups.
First-line nivolumab, bevacizumab, and paclitaxel therapy showed promising efficacy and manageable toxicity in patients with human epidermal growth factor receptor 2-negative metastatic breast cancer.
•First clinical trial to report efficacy of nivolumab, bevacizumab, and paclitaxel.•Objective response rates were promising (74% in HR+HER2− and 59% in patients with triple-negative breast cancer).•The median progression-free survival and overall survival were 14.0 months and 32.5 months, respectively.•Tumour programmed cell death-ligand 1 expression was not correlated with the efficacy of triple therapy.•Efficacy and prognosis were similar between serum vascular endothelial growth factor-high and vascular endothelial growth factor-low groups.
Background
Trastuzumab emtansine (T-DM1) is approved for the treatment of patients with human epidermal growth factor receptor 2 (HER2)-positive advanced breast cancer (ABC), and has high efficacy. ...However, some patients exhibit primary resistance to T-DM1, and thus methods that can predict resistance in clinical practice are needed. Genomic analysis of circulating tumor DNA (ctDNA) in plasma is a non-invasive and reproducible method. This study aimed to predict primary resistance to T-DM1 by combining genomic analysis of ctDNA and other clinicopathological features of patients with HER2-positive ABC.
Methods
The study population comprised 34 patients with HER2-positive ABC who had been treated with T-DM1. Correlations between clinicopathological characteristics of patients and primary resistance to T-DM1 were examined, and
HER2
gene copy number and
PIK3CA
gene mutations were analyzed using plasma ctDNA samples obtained from 16 patients before T-DM1 administration.
Results
Among the 34 patients, nine (26.5%) had progressive disease at the first efficacy analysis; these patients were considered to have primary resistance to T-DM1. No significant difference was found in the rate of primary resistance to T-DM1 between groups. Among 16 patients whose ctDNA was analyzed, four showed primary resistance to T-DM1. These four patients showed negative HER2 gene amplification in ctDNA and were ER-positive and/or PR-positive by immunohistochemistry.
Conclusions
HER2 gene amplification in ctDNA and ER and PR status may predict primary resistance to T-DM1. A liquid biopsy before the initiation of T-DM1 treatment could be a non-invasive way to predict whether a patient would exhibit primary resistance to T-DM1.