Overall Survival with Pembrolizumab in Early-Stage Triple-Negative Breast Cancer.

BACKGROUND: In patients with early-stage triple-negative breast cancer, the phase 3 KEYNOTE-522 trial showed significant improvements in pathological complete response and event-free survival with the addition of pembrolizumab to platinum-containing chemotherapy. Here we report the final results for overall survival. METHODS: We randomly assigned, in a 2:1 ratio, patients with previously untreated stage II or III triple-negative breast cancer to receive neoadjuvant therapy with four cycles of pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks plus paclitaxel and carboplatin, followed by four cycles of pembrolizumab or placebo plus doxorubicin-cyclophosphamide or epirubicin-cyclophosphamide. After definitive surgery, patients received adjuvant pembrolizumab (pembrolizumab-chemotherapy group) or placebo (placebo-chemotherapy group) every 3 weeks for up to nine cycles. The primary end points were pathological complete response and event-free survival. Overall survival was a secondary end point. RESULTS: Of the 1174 patients who underwent randomization, 784 were assigned to the pembrolizumab-chemotherapy group and 390 to the placebo-chemotherapy group. At the data-cutoff date (March 22, 2024), the median follow-up was 75.1 months (range, 65.9 to 84.0). The estimated overall survival at 60 months was 86.6% (95% confidence interval [CI], 84.0 to 88.8) in the pembrolizumab-chemotherapy group, as compared with 81.7% (95% CI, 77.5 to 85.2) in the placebo-chemotherapy group (P = 0.002). Adverse events were consistent with the established safety profiles of pembrolizumab and chemotherapy. CONCLUSIONS: Neoadjuvant pembrolizumab plus chemotherapy followed by adjuvant pembrolizumab resulted in a significant improvement, as compared with neoadjuvant chemotherapy alone, in overall survival among patients with early-stage triple-negative breast cancer. (Funded by Merck Sharp and Dohme, a subsidiary of Merck [Rahway, NJ]; KEYNOTE-522 ClinicalTrials.gov number, NCT03036488.).

Event-free Survival with Pembrolizumab in Early Triple-Negative Breast Cancer.

BACKGROUND: The addition of pembrolizumab to neoadjuvant chemotherapy led to a significantly higher percentage of patients with early triple-negative breast cancer having a pathological complete response (defined as no invasive cancer in the breast and negative nodes) at definitive surgery in an earlier analysis of this phase 3 trial of neoadjuvant and adjuvant therapy. The primary results regarding event-free survival in this trial have not been reported. METHODS: We randomly assigned, in a 2:1 ratio, patients with previously untreated stage II or III triple-negative breast cancer to receive neoadjuvant therapy with four cycles of pembrolizumab (at a dose of 200 mg) or placebo every 3 weeks plus paclitaxel and carboplatin, followed by four cycles of pembrolizumab or placebo plus doxorubicin-cyclophosphamide or epirubicin-cyclophosphamide. After definitive surgery, patients received adjuvant pembrolizumab (pembrolizumab-chemotherapy group) or placebo (placebo-chemotherapy group) every 3 weeks for up to nine cycles. The primary end points were pathological complete response (the results for which have been reported previously) and event-free survival, defined as the time from randomization to the date of disease progression that precluded definitive surgery, local or distant recurrence, occurrence of a second primary cancer, or death from any cause. Safety was also assessed. RESULTS: Of the 1174 patients who underwent randomization, 784 were assigned to the pembrolizumab-chemotherapy group and 390 to the placebo-chemotherapy group. The median follow-up at this fourth planned interim analysis (data cutoff, March 23, 2021) was 39.1 months. The estimated event-free survival at 36 months was 84.5% (95% confidence interval [CI], 81.7 to 86.9) in the pembrolizumab-chemotherapy group, as compared with 76.8% (95% CI, 72.2 to 80.7) in the placebo-chemotherapy group (hazard ratio for event or death, 0.63; 95% CI, 0.48 to 0.82; P<0.001). Adverse events occurred predominantly during the neoadjuvant phase and were consistent with the established safety profiles of pembrolizumab and chemotherapy. CONCLUSIONS: In patients with early triple-negative breast cancer, neoadjuvant pembrolizumab plus chemotherapy, followed by adjuvant pembrolizumab after surgery, resulted in significantly longer event-free survival than neoadjuvant chemotherapy alone. (Funded by Merck Sharp and Dohme, a subsidiary of Merck; KEYNOTE-522 ClinicalTrials.gov number, NCT03036488.).

Pembrolizumab for Early Triple-Negative Breast Cancer.

BACKGROUND: Previous trials showed promising antitumor activity and an acceptable safety profile associated with pembrolizumab in patients with early triple-negative breast cancer. Whether the addition of pembrolizumab to neoadjuvant chemotherapy would significantly increase the percentage of patients with early triple-negative breast cancer who have a pathological complete response (defined as no invasive cancer in the breast and negative nodes) at definitive surgery is unclear. METHODS: In this phase 3 trial, we randomly assigned (in a 2:1 ratio) patients with previously untreated stage II or stage III triple-negative breast cancer to receive neoadjuvant therapy with four cycles of pembrolizumab (at a dose of 200 mg) every 3 weeks plus paclitaxel and carboplatin (784 patients; the pembrolizumab-chemotherapy group) or placebo every 3 weeks plus paclitaxel and carboplatin (390 patients; the placebo-chemotherapy group); the two groups then received an additional four cycles of pembrolizumab or placebo, and both groups received doxorubicin-cyclophosphamide or epirubicin-cyclophosphamide. After definitive surgery, the patients received adjuvant pembrolizumab or placebo every 3 weeks for up to nine cycles. The primary end points were a pathological complete response at the time of definitive surgery and event-free survival in the intention-to-treat population. RESULTS: At the first interim analysis, among the first 602 patients who underwent randomization, the percentage of patients with a pathological complete response was 64.8% (95% confidence interval [CI], 59.9 to 69.5) in the pembrolizumab-chemotherapy group and 51.2% (95% CI, 44.1 to 58.3) in the placebo-chemotherapy group (estimated treatment difference, 13.6 percentage points; 95% CI, 5.4 to 21.8; P<0.001). After a median follow-up of 15.5 months (range, 2.7 to 25.0), 58 of 784 patients (7.4%) in the pembrolizumab-chemotherapy group and 46 of 390 patients (11.8%) in the placebo-chemotherapy group had disease progression that precluded definitive surgery, had local or distant recurrence or a second primary tumor, or died from any cause (hazard ratio, 0.63; 95% CI, 0.43 to 0.93). Across all treatment phases, the incidence of treatment-related adverse events of grade 3 or higher was 78.0% in the pembrolizumab-chemotherapy group and 73.0% in the placebo-chemotherapy group, including death in 0.4% (3 patients) and 0.3% (1 patient), respectively. CONCLUSIONS: Among patients with early triple-negative breast cancer, the percentage with a pathological complete response was significantly higher among those who received pembrolizumab plus neoadjuvant chemotherapy than among those who received placebo plus neoadjuvant chemotherapy. (Funded by Merck Sharp & Dohme [a subsidiary of Merck]; KEYNOTE-522 ClinicalTrials.gov number, NCT03036488.).

Pembrolizumab plus chemotherapy versus placebo plus chemotherapy for previously untreated locally recurrent inoperable or metastatic triple-negative breast cancer (KEYNOTE-355): a randomised, placebo-controlled, double-blind, phase 3 clinical trial.

BACKGROUND: Pembrolizumab monotherapy showed durable antitumour activity and manageable safety in patients with metastatic triple-negative breast cancer. We aimed to examine whether the addition of pembrolizumab would enhance the antitumour activity of chemotherapy in patients with metastatic triple-negative breast cancer. METHODS: In this randomised, placebo-controlled, double-blind, phase 3 trial, done in 209 sites in 29 countries, we randomly assigned patients 2:1 with untreated locally recurrent inoperable or metastatic triple-negative breast cancer using a block method (block size of six) and an interactive voice-response system with integrated web-response to pembrolizumab (200 mg) every 3 weeks plus chemotherapy (nab-paclitaxel; paclitaxel; or gemcitabine plus carboplatin) or placebo plus chemotherapy. Randomisation was stratified by type of on-study chemotherapy (taxane or gemcitabine-carboplatin), PD-L1 expression at baseline (combined positive score [CPS] ≥1 or <1), and previous treatment with the same class of chemotherapy in the neoadjuvant or adjuvant setting (yes or no). Eligibility criteria included age at least 18 years, centrally confirmed triple-negative breast cancer; at least one measurable lesion; provision of a newly obtained tumour sample for determination of triple-negative breast cancer status and PD-L1 status by immunohistochemistry at a central laboratory; an Eastern Cooperative Oncology Group performance status score 0 or 1; and adequate organ function. The sponsor, investigators, other study site staff (except for the unmasked pharmacist), and patients were masked to pembrolizumab versus saline placebo administration. In addition, the sponsor, the investigators, other study site staff, and patients were masked to patient-level tumour PD-L1 biomarker results. Dual primary efficacy endpoints were progression-free survival and overall survival assessed in the PD-L1 CPS of 10 or more, CPS of 1 or more, and intention-to-treat populations. The definitive assessment of progression-free survival was done at this interim analysis; follow-up to assess overall survival is continuing. For progression-free survival, a hierarchical testing strategy was used, such that testing was done first in patients with CPS of 10 or more (prespecified statistical criterion was α=0·00411 at this interim analysis), then in patients with CPS of 1 or more (α=0·00111 at this interim analysis, with partial alpha from progression-free survival in patients with CPS of 10 or more passed over), and finally in the intention-to-treat population (α=0·00111 at this interim analysis). This study is registered with ClinicalTrials.gov, NCT02819518, and is ongoing. FINDINGS: Between Jan 9, 2017, and June 12, 2018, of 1372 patients screened, 847 were randomly assigned to treatment, with 566 patients in the pembrolizumab-chemotherapy group and 281 patients in the placebo-chemotherapy group. At the second interim analysis (data cutoff, Dec 11, 2019), median follow-up was 25·9 months (IQR 22·8-29·9) in the pembrolizumab-chemotherapy group and 26·3 months (22·7-29·7) in the placebo-chemotherapy group. Among patients with CPS of 10 or more, median progression-free survival was 9·7 months with pembrolizumab-chemotherapy and 5·6 months with placebo-chemotherapy (hazard ratio [HR] for progression or death, 0·65, 95% CI 0·49-0·86; one-sided p=0·0012 [primary objective met]). Median progression-free survival was 7·6 and 5·6 months (HR, 0·74, 0·61-0·90; one-sided p=0·0014 [not significant]) among patients with CPS of 1 or more and 7·5 and 5·6 months (HR, 0·82, 0·69-0·97 [not tested]) among the intention-to-treat population. The pembrolizumab treatment effect increased with PD-L1 enrichment. Grade 3-5 treatment-related adverse event rates were 68% in the pembrolizumab-chemotherapy group and 67% in the placebo-chemotherapy group, including death in <1% in the pembrolizumab-chemotherapy group and 0% in the placebo-chemotherapy group. INTERPRETATION: Pembrolizumab-chemotherapy showed a significant and clinically meaningful improvement in progression-free survival versus placebo-chemotherapy among patients with metastatic triple-negative breast cancer with CPS of 10 or more. These findings suggest a role for the addition of pembrolizumab to standard chemotherapy for the first-line treatment of metastatic triple-negative breast cancer. FUNDING: Merck Sharp & Dohme Corp, a subsidiary of Merck & Co, Inc.

Prevalence, treatment patterns, and prognosis of low estrogen receptor-positive (1% to 10%) breast cancer: a single institution's experience in Korea.

PURPOSE: To determine prevalence, clinicopathological characteristics, initial treatments, and outcomes associated with low estrogen receptor (ER)-expressing invasive breast cancer. METHODS: This retrospective, non-interventional database study included patients undergoing surgery with curative intent for invasive ductal or lobular breast cancer. Patients were treated between January 2003-December 2012. Demographics, clinicopathological characteristics, initial treatments, and outcomes were abstracted from patient records. Patients were categorized using immunohistochemistry to determine ER, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) levels. ER-positive patients were subclassified as ER-low (1% to 10%) and ER-high (> 10%) according to the Allred Proportion Score. Disease-free survival (DFS) and overall survival (OS) were estimated by the Kaplan-Meier method and compared among groups by log-rank test. RESULTS: 5930 patients were included (median follow-up, 80.9 months). Of all patients included, 117 (2.0%) had ER-low tumors: 63 (53.8%) of whom had HER2- tumors and 54 (46.2%) HER2+ tumors. Five-year DFS and OS were highest in the ER-high/HER2- cohort (94.0% and 98.6%, respectively) and lowest in the triple-negative breast cancer (TNBC; 81.3% and 90.1%) and ER-low/HER2- (85.7% and 92.1%) cohorts. Menopausal status, elevated Ki-67, higher nuclear grade, higher tumor stage, presence of lymphovascular invasion, greater regional lymph node involvement, and larger tumor size were all potential prognostic factors for shorter DFS and OS. CONCLUSION: Patients with ER-low/HER2- breast cancer had similar clinicopathological characteristics, treatments, and outcomes as patients with TNBC irrespective of disease setting. Further research is needed to understand predictive and prognostic factors associated with ER-low/HER2- disease.

Evaluation of Pathologic Complete Response as a Surrogate for Long-Term Survival Outcomes in Triple-Negative Breast Cancer.

BACKGROUND: Pathologic complete response (pCR) is a common efficacy endpoint in neoadjuvant therapy trials for triple-negative breast cancer (TNBC). Previous studies have shown that pCR is strongly associated with improved long-term survival outcomes, including event-free survival (EFS) and overall survival (OS). However, the trial-level associations between treatment effect on pCR and long-term survival outcomes are not well established. This study sought to evaluate these associations by incorporating more recent clinical trials in TNBC. METHODS: A literature review identified published randomized controlled trials (RCTs) of neoadjuvant therapy for TNBC that reported results for both pCR and EFS/OS. Meta-regression models were performed to evaluate the association of treatment effect on pCR and EFS/OS. Sensitivity analyses were conducted to assess the impact of divergent study designs. RESULTS: Ten comparisons from 8 RCTs (N=2,478 patients) were identified from the literature review. The log (odds ratio) of pCR was a significant predictor of the log (hazard ratio) of EFS (P=.003), with a coefficient of determination of 0.68 (95% CI, 0.41-0.95). There was a weaker association between pCR and OS (P=.18), with a coefficient of determination of 0.24 (95% CI, 0.01-0.77). Consistent results were found in the exploratory analysis and sensitivity analyses. CONCLUSIONS: This is the first study that has shown a trial-level association between pCR and survival outcomes in TNBC. By incorporating the most up-to-date RCTs, this study showed a significant trial-level association between pCR and EFS. A positive association between pCR and OS was also recorded.

Current treatment landscape for patients with locally recurrent inoperable or metastatic triple-negative breast cancer: a systematic literature review.

BACKGROUND: Metastatic triple-negative breast cancer (mTNBC), an aggressive histological subtype, has poor prognosis. Chemotherapy remains standard of care for mTNBC, although no agent has been specifically approved for this breast cancer subtype. Instead, chemotherapies approved for metastatic breast cancer (MBC) are used for mTNBC (National Comprehensive Cancer Network Guidelines [NCCN] v1.2019). Atezolizumab in combination with nab-paclitaxel was recently approved for programmed death-ligand 1 (PD-L1)-positive locally advanced or metastatic TNBC. Published historical data were reviewed to characterize the efficacy of NCCN-recommended (v1.2016) agents as first-line (1L) and second-line or later (2L+) treatment for patients with locally recurrent inoperable or metastatic TNBC (collectively termed mTNBC herein). METHODS: A systematic literature review was performed, examining clinical efficacy of therapies for mTNBC based on NCCN v1.2016 guideline recommendations. Data from 13 studies, either published retrospective mTNBC subgroup analyses based on phase III trials in MBC or phase II trials in mTNBC, were included. RESULTS: A meta-analysis of mTNBC subgroups from three phase III trials in 1L MBC reported pooled objective response rate (ORR) of 23%, median overall survival (OS) of 17.5 months, and median progression-free survival (PFS) of 5.4 months with single-agent chemotherapy. In two subgroup analyses from a phase III study and a phase II trial (n = 40 each), median duration of response (DOR) to 1L chemotherapy for mTNBC was 4.4-6.6 months; therefore, responses were not durable. A meta-analysis of seven cohorts showed the pooled ORR for 2L+ chemotherapy was 11% (95% CI, 9-14%). Median DOR to 2L+ chemotherapy in mTNBC was also limited (4.2-5.9 months) per two subgroup analyses from a phase III study. No combination chemotherapy regimens recommended by NCCN v1.2016 for treatment of MBC showed superior OS to single agents. CONCLUSIONS: Chemotherapies have limited effectiveness and are associated with unfavorable toxicity profiles, highlighting a considerable unmet medical need for improved therapeutic options in mTNBC. In addition to the recently approved combination of atezolizumab and nab-paclitaxel for PD-L1-positive mTNBC, new treatments resulting in durable clinical responses, prolonged survival, and manageable safety profile would greatly benefit patients with mTNBC.

Adjuvant lapatinib for women with early-stage HER2-positive breast cancer: a randomised, controlled, phase 3 trial.

BACKGROUND: Worldwide, many patients with HER2-positive early stage breast cancer do not receive trastuzumab-the standard adjuvant treatment. We investigated the efficacy and safety of adjuvant lapatinib for patients with trastuzumab-naive HER2-positive early-stage breast cancer, started at any time after diagnosis. METHODS: This study was a placebo-controlled, multicentre, randomised phase 3 trial. Women outpatients from 405 [corrected] centres in 33 countries [corrected] with HER2-positive early-breast cancer who had previously received adjuvant chemotherapy but not trastuzumab were randomly assigned (1:1) to receive daily lapatinib (1500 mg) or daily placebo for 12 months. Randomisation was done with a computer-generated sequence, stratified by time since diagnosis, lymph node involvement at diagnosis, and tumour hormone-receptor status. Investigators, site staff, and patients were masked to treatment assignment. The primary endpoint was disease-free survival in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00374322. FINDINGS: Between August, 2006, and May, 2008, 3161 women were enrolled and 3147 were assigned to lapatinib (n=1571) or placebo (n=1576). After a median follow-up of 47·4 months (range 0·4-60·0) in the lapatinib group and 48·3 (0·7-61·3) in the placebo group, 210 (13%) disease-free survival events had occurred in the lapatinib group versus 264 (17%) in the placebo group (hazard ratio [HR] 0·83, 95% CI 0·70-1·00; p=0·053). Central review of HER2 status showed that only 2490 (79%) of the randomised women were HER2-positive. 157 (13%) of 1230 confirmed HER2-positive patients in the lapatinib group and in 208 (17%) of 1260 in the placebo group had a disease-free survival event (HR 0·82, 95% 0·67-1·00; p=0·04). Serious adverse events occurred in 99 (6%) of 1573 patients taking lapatinib and 77 (5%) of 1574 patients taking placebo, with higher incidences of grade 3-4 diarrhoea (97 [6%] vs nine [<1%]), rash (72 [5%] vs three [<1%]), and hepatobiliary disorders (36 [2%] vs one [<1%]). INTERPRETATION: Our data show that there was no significant difference in disease-free survival between groups when analysed in the intention-to-treat population. However, exploratory analyses restricted to patients who had HER2-positive disease confirmed by central fluorescence in-situ hybridisation review suggested marginal benefit with lapatinib in terms of disease-free survival. Thus lapatinib might be an option for women with HER2-positive breast cancer who do not or cannot receive adjuvant trastuzumab. FUNDING: GlaxoSmithKline.

A Narrative Review of the Clinical, Humanistic, and Economic Value of Pembrolizumab-Based Immunotherapy for the Treatment of Breast and Gynecologic Cancers.

Breast and gynecologic cancers are common across the world and are associated with substantial societal and economic burden. Pembrolizumab was among the first immune checkpoint inhibitors targeting programmed cell death protein 1 to be approved for the treatment of patients with triple-negative breast cancer, cervical cancer, and endometrial cancer. Recent clinical trials have established pembrolizumab regimens as a standard of care treatment for these tumor types. Clinical data are further supported by patient-reported outcome, cost-effectiveness, and real-world evidence. Pembrolizumab monotherapy and combination regimens do not negatively influence health-related quality of life and are cost-effective relative to comparators. Ongoing phase 3 studies with pembrolizumab will expand the current understanding of its use in breast and gynecologic cancers. Several of these studies are in patients with early-stage disease with the hope of curing patients. The main objective of this review is to summarize the clinical, humanistic, and economic value of pembrolizumab in these settings and to describe the future challenges for patients, caregivers, clinicians, and payers.

Pembrolizumab or Placebo Plus Adjuvant Chemotherapy With or Without Radiotherapy For Newly Diagnosed, High-Risk Endometrial Cancer: Results in Mismatch Repair-Deficient Tumors.

Mismatch repair-deficient (dMMR) endometrial cancer is an inflamed phenotype with poor outcomes when meeting high-risk criteria and limited treatment options in the adjuvant setting. We report protocol-prespecified subgroup analysis of patients with dMMR tumors from the phase 3 ENGOT-en11/GOG-3053/KEYNOTE-B21 study (NCT04634877) in newly-diagnosed, high-risk endometrial cancer after surgery with curative intent. Patients were randomized to pembrolizumab 200mg or placebo (6 cycles) plus carboplatin-paclitaxel (4-6 cycles) Q3W, then pembrolizumab 400mg or placebo Q6W (6 cycles), respectively. MMR status was a stratification factor. Patients received radiotherapy at investigator discretion. Investigator-assessed disease-free survival (DFS) was a primary endpoint. No formal hypothesis testing was performed for subgroup analysis. In the intention-to-treat population, 141 patients in the pembrolizumab arm and 140 in the placebo arm had dMMR tumors. At this interim analysis, hazard ratio for DFS favored pembrolizumab (0.31; 95%CI, 0.14-0.69); median DFS was not reached in either group. Two-year DFS rates were 92.4% (95%CI, 84.4%-96.4%) and 80.2% (95%CI, 70.8%-86.9%), respectively. No new safety signals occurred. Longer-term follow-up of outcomes will be evaluated at final analysis. Preplanned subgroup analysis based on the study's stratification factors suggests that pembrolizumab plus chemotherapy improves DFS and is clinically relevant for patients with dMMR tumors in the curative-intent setting.

Lapatinib with trastuzumab for HER2-positive early breast cancer (NeoALTTO): a randomised, open-label, multicentre, phase 3 trial.

BACKGROUND: The anti-HER2 monoclonal antibody trastuzumab and the tyrosine kinase inhibitor lapatinib have complementary mechanisms of action and synergistic antitumour activity in models of HER2-overexpressing breast cancer. We argue that the two anti-HER2 agents given together would be better than single-agent therapy. METHODS: In this parallel groups, randomised, open-label, phase 3 study undertaken between Jan 5, 2008, and May 27, 2010, women from 23 countries with HER2-positive primary breast cancer with tumours greater than 2 cm in diameter were randomly assigned to oral lapatinib (1500 mg), intravenous trastuzumab (loading dose 4 mg/kg [DOSAGE ERROR CORRECTED], subsequent doses 2 mg/kg), or lapatinib (1000 mg) plus trastuzumab. Treatment allocation was by stratified, permuted blocks randomisation, with four stratification factors. Anti-HER2 therapy alone was given for the first 6 weeks; weekly paclitaxel (80 mg/m(2)) was then added to the regimen for a further 12 weeks, before definitive surgery was undertaken. After surgery, patients received adjuvant chemotherapy followed by the same targeted therapy as in the neoadjuvant phase to 52 weeks. The primary endpoint was the rate of pathological complete response (pCR), analysed by intention to treat. This trial is registered with ClinicalTrials.gov, NCT00553358. FINDINGS: 154 patients received lapatinib, 149 trastuzumab, and 152 the combination. pCR rate was significantly higher in the group given lapatinib and trastuzumab (78 of 152 patients [51·3%; 95% CI 43·1-59·5]) than in the group given trastuzumab alone (44 of 149 patients [29·5%; 22·4-37·5]; difference 21·1%, 9·1-34·2, p=0·0001). We recorded no significant difference in pCR between the lapatinib (38 of 154 patients [24·7%, 18·1-32·3]) and the trastuzumab (difference -4·8%, -17·6 to 8·2, p=0·34) groups. No major cardiac dysfunctions occurred. Frequency of grade 3 diarrhoea was higher with lapatinib (36 patients [23·4%]) and lapatinib plus trastuzumab (32 [21·1%]) than with trastuzumab (three [2·0%]). Similarly, grade 3 liver-enzyme alterations were more frequent with lapatinib (27 [17·5%]) and lapatinib plus trastuzumab (15 [9·9%]) than with trastuzumab (11 [7·4%]). INTERPRETATION: Dual inhibition of HER2 might be a valid approach to treatment of HER2-positive breast cancer in the neoadjuvant setting. FUNDING: GlaxoSmithKline.

Analysis of regional timelines to set up a global phase III clinical trial in breast cancer: the adjuvant lapatinib and/or trastuzumab treatment optimization experience.

PURPOSE: This study measured the time taken for setting up the different facets of adjuvant lapatinib and/or trastuzumab treatment optimization (ALTTO), an nternational phase III study being conducted in 44 participating countries. METHODS: Time to regulatory authority (RA) approval, time to ethics committee/institutional review board (EC/IRB) approval, time from study approval by EC/IRB to first randomized patient, and time from first to last randomized patient were prospectively collected in the ALTTO study. Analyses were conducted by grouping countries into either geographic regions or economic classes as per the World Bank's criteria. RESULTS: South America had a significantly longer time to RA approval (median: 236 days, range: 21-257 days) than Europe (median: 52 days, range: 0-151 days), North America (median: 26 days, range: 22-30 days), and Asia-Pacific (median: 62 days, range: 37-75 days). Upper-middle economies had longer times to RA approval (median: 123 days, range: 21-257 days) than high-income (median: 47 days, range: 0-112 days) and lower-middle income economies (median: 57 days, range: 37-62 days). No significant difference was observed for time to EC/IRB approval across the studied regions (median: 59 days, range 0-174 days). Overall, the median time from EC/IRB approval to first recruited patient was 169 days (range: 26-412 days). CONCLUSION: This study highlights the long time intervals required to activate a global phase III trial. Collaborative research groups, pharmaceutical industry sponsors, and regulatory authorities should analyze the current system and enter into dialogue for optimizing local policies. This would enable faster access of patients to innovative therapies and enhance the efficiency of clinical research.

Eribulin Plus Pembrolizumab in Patients with Metastatic Triple-Negative Breast Cancer (ENHANCE 1): A Phase Ib/II Study.

PURPOSE: As monotherapies, eribulin (chemotherapy) and pembrolizumab (immunotherapy) have shown promise for patients with metastatic triple-negative breast cancer (mTNBC). This phase Ib/II study examined eribulin plus pembrolizumab as a potential mTNBC treatment in first-line and later-line settings. PATIENTS AND METHODS: In this open-label, single-arm, phase Ib/II study, eligible patients had mTNBC, measurable disease, and ≤2 prior systemic anticancer therapies in the metastatic setting. Patients were enrolled by number of prior systemic anticancer therapies (stratum 1: 0 vs stratum 2: 1-2) in the metastatic setting and further analyzed by tumor programmed death-ligand 1 (PD-L1) expression status. All patients received intravenous eribulin 1.4 mg/m2 on day 1 and day 8, plus intravenous pembrolizumab 200 mg on day 1, of 21-day cycles. The primary objectives were the safety, tolerability, and objective response rate (ORR) of this combination. RESULTS: The study included 167 patients (phase Ib, n = 7; phase II, n = 160). The most common treatment-emergent adverse events were fatigue (66%), nausea (58%), peripheral sensory neuropathy (41%), alopecia (40%), and constipation (37%). ORRs were 25.8% [95% confidence interval (CI): 15.8-38.0] for stratum 1 (n = 66) and 21.8% (95% CI: 14.2-31.1) for stratum 2 (n = 101). Patients with PD-L1-positive tumors (combined positive score ≥1) had numerically higher ORR than those with PD-L1-negative tumors, particularly in stratum 1 [stratum 1: 34.5% (95% CI: 17.9-54.3) vs 16.1% (95% CI: 5.5-33.7); stratum 2, 24.4% (95% CI: 12.9-39.5) vs 18.2% (95% CI: 8.2-32.7)]. CONCLUSIONS: Eribulin plus pembrolizumab was generally well tolerated and showed promising antitumor activity in mTNBC. Efficacy outcomes appeared influenced by line of therapy and PD-L1 status.

Association of Pathologic Complete Response with Long-Term Survival Outcomes in Triple-Negative Breast Cancer: A Meta-Analysis.

Pathologic complete response (pCR) following neoadjuvant therapy has been associated with improved event-free survival (EFS) and overall survival (OS) in early-stage breast cancer. The magnitude of this association varies by breast cancer subtype, yet further research focusing on subtype-specific populations is limited. Here we provide an updated and comprehensive evaluation of the association between pCR and survival outcomes in triple-negative breast cancer (TNBC). A literature review identified neoadjuvant studies, including clinical trials, real-world cohort studies, and studies that pooled multiple trials or cohorts, which reported EFS/OS results by pCR in patients with early-stage TNBC. Meta-analyses were performed to evaluate the association between pCR and EFS/OS and to predict long-term survival outcomes based on pCR status. Sensitivity analyses were conducted to assess the impact of cross-study variations. Twenty-five studies with over 4,000 patients with TNBC were identified. A synthesis of evidence from these studies suggested substantial improvement in EFS and OS for pCR versus non-pCR [EFS HR (95% confidence interval): 0.24 (0.20-0.29); OS: 0.19 (0.15-0.24)]; consistent results were reported in sensitivity analyses. Collectively, our findings suggest that adjuvant therapy is associated with improved EFS/OS in patients with TNBC who received neoadjuvant therapy, regardless of pCR status.

Pembrolizumab in Patients With Advanced Triple-Negative Breast Cancer: Phase Ib KEYNOTE-012 Study.

PURPOSE: Immune checkpoint inhibition has been demonstrated to be an effective anticancer strategy. Several lines of evidence support the study of immunotherapy in triple-negative breast cancer (TNBC). We assessed the safety and antitumor activity of the programmed cell death protein 1 (PD-1) inhibitor pembrolizumab in patients with advanced TNBC. METHODS: KEYNOTE-012 (ClinicalTrials.gov identifier: NCT01848834) was a multicenter, nonrandomized phase Ib trial of single-agent pembrolizumab given intravenously at 10 mg/kg every 2 weeks to patients with advanced PD-L1-positive (expression in stroma or ≥ 1% of tumor cells by immunohistochemistry) TNBC, gastric cancer, urothelial cancer, and head and neck cancer. This report focuses on the TNBC cohort. RESULTS: Among 111 patients with TNBC whose tumor samples were screened for PD-L1 expression, 58.6% had PD-L1-positive tumors. Thirty-two women (median age, 50.5 years; range, 29 to 72 years) were enrolled and assessed for safety and antitumor activity. The median number of doses administered was five (range, 1 to 36 doses). Common toxicities were mild and similar to those observed in other tumor cohorts (eg, arthralgia, fatigue, myalgia, and nausea), and included five (15.6%) patients with grade ≥ 3 toxicity and one treatment-related death. Among the 27 patients who were evaluable for antitumor activity, the overall response rate was 18.5%, the median time to response was 17.9 weeks (range, 7.3 to 32.4 weeks), and the median duration of response was not yet reached (range, 15.0 to ≥ 47.3 weeks). CONCLUSION: This phase Ib study describes preliminary evidence of clinical activity and a potentially acceptable safety profile of pembrolizumab given every 2 weeks to patients with heavily pretreated, advanced TNBC. A single-agent phase II study examining a 200-mg dose given once every 3 weeks (ClinicalTrials.gov identifier: NCT02447003) is ongoing.

Phase I study of the MEK inhibitor trametinib in combination with the AKT inhibitor afuresertib in patients with solid tumors and multiple myeloma.

PURPOSE: To identify the maximum tolerated dose (MTD) and recommended Phase II dose of MEK/AKT inhibitor combination of trametinib and afuresertib. PATIENTS AND METHODS: Eligibility criteria were advanced solid tumors, 18 years or older, Eastern Cooperative Oncology Group performance status 0 or 1, and adequate organ function. Exclusion criteria included Type 1 diabetes, active GI disease, leptomeningeal disease, or current evidence/risk of retinal venous occlusion/central serous retinopathy. Clinical safety parameters and response were evaluated and analyzed. RESULTS: Twenty patients were enrolled. Dose-limiting toxicities (Grade 2 esophagitis; Grade 3 aspartate aminotransferase increased, mucosal inflammation and hypokalemia) were reported at starting dose (1.5 mg trametinib/50 mg afuresertib once daily continuously), exceeding the MTD. Subsequent de-escalation cohorts (1.5 mg/25 mg or 1.0 mg/50 mg trametinib/afuresertib) were defined as MTDs for continuous dosing. Intermittent dosing schedule [1.5 mg trametinib (continuous)/50 mg afuresertib (Days 1-10 every 28 days)] was evaluated and considered tolerable. No patients were enrolled in Phase II. The most common adverse events reported (≥10 % of all patients) included: diarrhea (60 %), dermatitis acneiform (55 %), maculo-papular rash (45 %), fatigue (30 %), dry skin (25 %), nausea (25 %), dyspnea (20 %), and vomiting (20 %). One partial response (BRAF wild-type melanoma) was reported; four patients had stable disease as best response. CONCLUSION: Continuous daily dosing of trametinib/afuresertib combination was poorly tolerated. Evaluation of intermittent dose schedule showed greater tolerability. Given the interest in combination treatment regimens of MAPK and PI3K/AKT pathway inhibitors, further study of intermittent dose schedule or combination of trametinib with more selective inhibitors may be warranted.

Assessment of the drug interaction potential and single- and repeat-dose pharmacokinetics of the BRAF inhibitor dabrafenib.

The induction of CYP2C9 by dabrafenib using S-warfarin as a probe and the effects of a CYP3A inhibitor (ketoconazole) and a CYP2C8 inhibitor (gemfibrozil) on dabrafenib pharmacokinetics were evaluated in patients with BRAF V600 mutation-positive tumors. Dabrafenib single- and repeat-dose pharmacokinetics were also evaluated. S-warfarin AUC(0- ∞) decreased 37% and Cmax increased 18% with dabrafenib. Dabrafenib AUC(0- τ) and C(max) increased 71% and 33%, respectively, with ketoconazole. Hydroxy- and desmethyl-dabrafenib AUC(0-τ) increased 82% and 68%, respectively, and AUC for carboxy-dabrafenib decreased 16%. Dabrafenib AUC(0-τ) increased 47%, with no change in C(max), after gemfibrozil co-administration. Gemfibrozil did not affect systemic exposure to dabrafenib metabolites. Single- and repeat-dose dabrafenib pharmacokinetics were consistent with previous reports. All cohorts used the commercial capsules. More-frequent monitoring of international normalized ratios is recommended in patients receiving warfarin during initiation or discontinuation of dabrafenib. Substitution of strong inhibitors or strong inducers of CYP3A or CYP2C8 is recommended during treatment with dabrafenib.

Health-related quality of life impact in a randomised phase III study of the combination of dabrafenib and trametinib versus dabrafenib monotherapy in patients with BRAF V600 metastatic melanoma.

AIM: To present the impact of treatments on health-related quality of life (HRQoL) from the double-blind, randomised phase III COMBI-d study that investigated the combination of dabrafenib and trametinib versus dabrafenib monotherapy in patients with BRAF V600E/K-mutant metastatic melanoma. COMBI-d showed significantly prolonged progression-free survival for the combination. METHODS: HRQoL was evaluated using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-C30, a generic cancer questionnaire (completed at baseline, during study treatment, at progression and post progression) assessing various dimensions (global health/QoL, functional status, and symptom impact). A mixed-model, repeated-measures analyses of covariance evaluated differences between arms. RESULTS: Questionnaire completion rates were >95% at baseline, >85% to week 40 and >70% at disease progression. Baseline scores across both arms were comparable for all dimensions. Global health dimension scores were significantly better at weeks 8, 16 and 24 for patients receiving the combination during treatment and at progression. The majority of functional dimension scores (physical, social, role, emotional and cognitive functioning) trended in favour of the combination. Pain scores were significantly improved and clinically meaningful (6-13 point difference) for patients receiving the combination for all follow-up assessments versus those receiving dabrafenib monotherapy. For other symptom dimensions (nausea and vomiting, diarrhoea, dyspnoea, and constipation), scores trended in favour of dabrafenib monotherapy. CONCLUSION: This analysis demonstrates that the combination of dabrafenib and trametinib provides better preservation of HRQoL and pain improvements versus dabrafenib monotherapy while also delaying progression. (Clinicaltrials.gov registration number: NCT01584648).

18F-FDG PET/CT for early prediction of response to neoadjuvant lapatinib, trastuzumab, and their combination in HER2-positive breast cancer: results from Neo-ALTTO.

UNLABELLED: Molecular imaging receives increased attention for selecting patients who will benefit from targeted anticancer therapies. Neo-ALTTO (Neoadjuvant Lapatinib and/or Trastuzumab Treatment Optimisation) enrolled 455 women with invasive human epidermal growth factor receptor 2 (HER2)-positive breast cancer and compared rates of pathologic complete response (pCR) to neoadjuvant lapatinib, trastuzumab, and their combination. Each anti-HER2 therapy was given alone for 6 wk, followed by 12 wk of the same therapy plus weekly paclitaxel. The early metabolic effects of the anti-HER2 therapies on the primary tumors and their predictive values for pCR were assessed in a subset of patients. METHODS: Eighty-six patients underwent (18)F-FDG PET/CT at baseline and weeks 2 and 6 of anti-HER2 treatment. An imaging core laboratory provided central validation, and 2 independent reviewers, masked to assigned treatment arm and clinical outcomes, performed consensus (18)F-FDG PET/CT readings. Maximum standardized uptake value (SUVmax) reductions from baseline were used to measure metabolic response. RESULTS: Seventy-seven of the 86 enrolled patients presented an evaluable baseline (18)F-FDG PET/CT scan; of these, 68 and 66 were evaluable at weeks 2 and 6, respectively. Metabolic responses in the primary tumors were evident after 2 wk of targeted therapy and correlated highly with metabolic responses at week 6 (R(2) = 0.81). pCRs were associated with greater SUVmax reductions at both time points. Mean SUVmax reductions for pCR and non-pCR, respectively, were 54.3% versus 32.8% at week 2 (P = 0.02) and 61.5% versus 34.1% at week 6 (P = 0.02). (18)F-FDG PET/CT metabolic response rates at weeks 2 and 6 were 71.6% and 60%, respectively using European Organization for Research and Treatment of Cancer criteria; pCR rates were twice as high for (18)F-FDG PET/CT responders than nonresponders (week 2: 42% vs. 21%, P = 0.12; week 6: 44% vs. 19%, P = 0.05). CONCLUSION: Early metabolic assessment using (18)F-FDG PET/CT can identify patients with an increased likelihood of pCR after neoadjuvant trastuzumab, lapatinib, or their combination when given with chemotherapy.

Overall survival benefit with lapatinib in combination with trastuzumab for patients with human epidermal growth factor receptor 2-positive metastatic breast cancer: final results from the EGF104900 Study.

PURPOSE: Phase III EGF104900 data demonstrated that lapatinib plus trastuzumab significantly improved progression-free survival (PFS) and clinical benefit rate versus lapatinib monotherapy, offering a chemotherapy-free option for patients with heavily pretreated human epidermal growth factor receptor 2 (HER2) -positive metastatic breast cancer (MBC). Final planned overall survival (OS) analysis from EGF104900 is reported here. PATIENTS AND METHODS: Patients with HER2-positive MBC whose disease progressed during prior trastuzumab-based therapies were randomly assigned to receive lapatinib monotherapy or lapatinib in combination with trastuzumab. OS and updated PFS data are presented using Kaplan-Meier curves and log-rank tests stratified for hormone receptor and visceral disease status. Subgroup analyses were conducted to identify characteristics of patients deriving the greatest clinical benefit. RESULTS: In this updated final analysis of all patients randomly assigned with strata (n = 291), lapatinib plus trastuzumab continued to show superiority to lapatinib monotherapy in PFS (hazard ratio [HR], 0.74; 95% CI, 0.58 to 0.94; P = .011) and offered significant OS benefit (HR, 0.74; 95% CI, 0.57 to 0.97; P = .026). Improvements in absolute OS rates were 10% at 6 months and 15% at 12 months in the combination arm compared with the monotherapy arm. Multiple baseline factors, including Eastern Cooperative Oncology Group performance status of 0, nonvisceral disease, < three metastatic sites, and less time from initial diagnosis until random assignment, were associated with improved OS. Incidence of adverse events was consistent with previously reported rates. CONCLUSION: These data demonstrated a significant 4.5-month median OS advantage with the lapatinib and trastuzumab combination and support dual HER2 blockade in patients with heavily pretreated HER2-positive MBC.