•Everolimus plus exemestane is an established treatment for NSAI-resistant MBC.•New everolimus-based combinations under investigation will expand treatment options.•Everolimus remains an important ...treatment in a changing MBC landscape.
Metastatic breast cancer (MBC) is the leading cause of cancer-related morbidity and mortality among women worldwide. Endocrine therapy is the standard of care for the most common subtype of MBC, hormone-receptor positive (HR+), human epidermal growth factor receptor 2-negative (HER2−) disease. Advances in treating this type of MBC have focused on improving the efficacy of endocrine therapy by adding agents that target specific molecular pathways of breast cancer cell growth and survival. The combination of the aromatase inhibitor exemestane and the mammalian target of rapamycin inhibitor, everolimus, more than doubled median progression-free survival compared with exemestane alone (7.8 vs 3.2 months, respectively; hazard ratio 0.45 95% confidence interval 0.38–0.54; log rank P < 0.0001) in the BOLERO-2 study in postmenopausal women with HR+, HER2− locally advanced or metastatic breast cancer that had recurred or progressed on prior non-steroidal aromatase inhibitor therapy. In addition, everolimus plus exemestane was associated with a manageable safety profile. The results of BOLERO-2 led to regulatory approval of everolimus plus exemestane. Additional everolimus-based combinations have been or are under investigation in the HR+, HER2− MBC setting, including combinations with letrozole, fulvestrant, ribociclib, tamoxifen, and chemotherapy. This review summarizes key data on everolimus-based combinations focusing on efficacy, safety, biomarkers, quality of life, and health economic outcomes. These data are discussed in the context of the changing MBC treatment algorithm to provide insights into the clinical relevance of everolimus-based combinations.
An earlier report documented significant improvement in progression-free survival among patients with metastatic breast cancer treated with fulvestrant and a cyclin-dependent kinase inhibitor, ...ribociclib. With longer follow-up, it is clear that fulvestrant and ribociclib also prolong overall survival.
Resistance to hormone therapy through activation of cellular pathways involving mTOR can develop in postmenopausal hormone-receptor–positive breast cancer. Adding an mTOR inhibitor to an aromatase ...inhibitor improved outcomes in patients who had disease progression during hormone therapy.
Endocrine therapy is the cornerstone of treatment for patients with hormone-receptor (HR)–positive advanced breast cancer. In postmenopausal patients, aromatase inhibitors (e.g., letrozole and anastrozole) have become the treatment of choice in first-line therapy.
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Unfortunately, not all patients have a response to first-line endocrine therapy (primary or de novo resistance), and even patients who have a response will eventually relapse (acquired resistance). On disease progression, second-line treatment options include other classes of aromatase inhibitors (steroidal or nonsteroidal) and the estrogen-receptor (ER) antagonists fulvestrant and tamoxifen.
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The study of resistance to endocrine therapies in HR-positive breast cancer has aimed at . . .
Purpose This phase III study evaluated ribociclib plus fulvestrant in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer who were ...treatment naïve or had received up to one line of prior endocrine therapy in the advanced setting. Patients and Methods Patients were randomly assigned at a two-to-one ratio to ribociclib plus fulvestrant or placebo plus fulvestrant. The primary end point was locally assessed progression-free survival. Secondary end points included overall survival, overall response rate, and safety. Results A total of 484 postmenopausal women were randomly assigned to ribociclib plus fulvestrant, and 242 were assigned to placebo plus fulvestrant. Median progression-free survival was significantly improved with ribociclib plus fulvestrant versus placebo plus fulvestrant: 20.5 months (95% CI, 18.5 to 23.5 months) versus 12.8 months (95% CI, 10.9 to 16.3 months), respectively (hazard ratio, 0.593; 95% CI, 0.480 to 0.732; P < .001). Consistent treatment effects were observed in patients who were treatment naïve in the advanced setting (hazard ratio, 0.577; 95% CI, 0.415 to 0.802), as well as in patients who had received up to one line of prior endocrine therapy for advanced disease (hazard ratio, 0.565; 95% CI, 0.428 to 0.744). Among patients with measurable disease, the overall response rate was 40.9% for the ribociclib plus fulvestrant arm and 28.7% for placebo plus fulvestrant. Grade 3 adverse events reported in ≥ 10% of patients in either arm (ribociclib plus fulvestrant v placebo plus fulvestrant) were neutropenia (46.6% v 0%) and leukopenia (13.5% v 0%); the only grade 4 event reported in ≥ 5% of patients was neutropenia (6.8% v 0%). Conclusion Ribociclib plus fulvestrant might represent a new first- or second-line treatment option in hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer.
Summary Background Stomatitis is a class effect associated with the inhibition of mTOR and is associated with everolimus therapy for breast cancer. Topical steroids might reduce stomatitis incidence ...and severity, and the need for dose reductions and interruptions of everolimus. Anecdotal use of topical steroid oral prophylaxis has been reported in patients with breast cancer. We aimed to assess dexamethasone-based mouthwash for prevention of stomatitis in patients with breast cancer. Methods This US-based, multicentre, single-arm, phase 2 prevention study enrolled women aged 18 years and older with postmenopausal status who had histologically or cytologically confirmed metastatic hormone receptor-positive, HER2-negative breast cancer. Beginning on day 1 of cycle 1, patients received everolimus 10 mg plus exemestane 25 mg daily, with 10 mL of alcohol-free dexamethasone 0·5 mg per 5 mL oral solution (swish for 2 min and spit, four times daily for 8 weeks). After 8 weeks, dexamethasone mouthwash could be continued for up to eight additional weeks at the discretion of the clinician and patient. The primary endpoint was incidence of grade 2 or worse stomatitis by 8 weeks assessed in the full analysis set (patients who received at least one dose of everolimus and exemestane and at least one confirmed dose of dexamethasone mouthwash) versus historical controls from the BOLERO-2 trial (everolimus and exemestane treatment in patients with hormone receptor-positive advanced breast cancer who were not given dexamethasone mouthwash for prevention of stomatitis). This trial is registered at ClinicalTrials.gov , number NCT02069093. Findings Between May 28, 2014, and Oct 8, 2015, we enrolled 92 women; 85 were evaluable for efficacy. By 8 weeks, the incidence of grade 2 or worse stomatitis was two (2%) of 85 patients (95% CI 0·29–8·24), versus 159 (33%) of 482 patients (95% CI 28·8–37·4) for the duration of the BOLERO-2 study. Overall, 83 (90%) of 92 patients had at least one adverse event. The most frequently reported grade 3 and 4 adverse events in the safety set were hyperglycaemia (seven 8% of 92 patients), rash (four 4%), and dyspnoea (three 3%). Serious adverse events were reported in 20 (22%) patients; six (7%) were deemed treatment related, with dyspnoea (three 3%) and pneumonia (two 2%) reported most frequently. 12 (13%) of 92 patients had adverse events suspected to be related to treatment that led to discontinuation of everolimus and exemestane (the most common were rash, hyperglycaemia, and stomatitis, which each affected two 2% patients). Interpretation Prophylactic use of dexamethasone oral solution substantially reduced the incidence and severity of stomatitis in patients receiving everolimus and exemestane and could be a new standard of oral care for patients receiving everolimus and exemestane therapy. Funding Novartis Pharmaceuticals Corporation.
Summary Background Patients with melanoma harbouring Val600 BRAF mutations benefit from treatment with BRAF inhibitors. However, no targeted treatments exist for patients with BRAF wild-type tumours, ...including those with NRAS mutations. We aimed to assess the use of MEK162, a small-molecule MEK1/2 inhibitor, in patients with NRAS -mutated or Val600 BRAF -mutated advanced melanoma. Methods In our open-label, non-randomised, phase 2 study, we assigned patients with NRAS -mutated or BRAF -mutated advanced melanoma to one of three treatment arms on the basis of mutation status. Patients were enrolled at university hospitals or private cancer centres in Europe and the USA. The three arms were: twice-daily MEK162 45 mg for NRAS -mutated melanoma, twice-daily MEK162 45 mg for BRAF -mutated melanoma, and twice-daily MEK162 60 mg for BRAF -mutated melanoma. Previous treatment with BRAF inhibitors was permitted, but previous MEK inhibitor therapy was not allowed. The primary endpoint was the proportion of patients who had an objective response (ie, a complete response or confirmed partial response). We report data for the 45 mg groups. We assessed clinical activity in all patients who received at least one dose of MEK162 and in patients assessable for response (with two available CT scans). This study is registered with ClinicalTrials.gov , number NCT01320085 , and is currently recruiting additional patients with NRAS mutations (based on a protocol amendment). Findings Between March 31, 2011, and Jan 17, 2012, we enrolled 71 patients who received at least one dose of MEK162 45 mg. By Feb 29, 2012 (data cutoff), median follow-up was 3·3 months (range 0·6–8·7; IQR 2·2–5·0). No patients had a complete response. Six (20%) of 30 patients with NRAS -mutated melanoma had a partial response (three confirmed) as did eight (20%) of 41 patients with BRAF -mutated melanoma (two confirmed). The most frequent adverse events were acneiform dermatitis (18 60% patients with NRAS -mutated melanoma and 15 37% patients with the BRAF -mutated melanoma), rash (six 20% and 16 39%), peripheral oedema (ten 33% and 14 34%), facial oedema (nine 30% and seven 17%), diarrhoea (eight 27% and 15 37%), and creatine phosphokinase increases (11 37% and nine 22%). Increased creatine phosphokinase was the most common grade 3–4 adverse event (seven 23% and seven 17%). Four patients had serious adverse events (two per arm), which included diarrhoea, dehydration, acneiform dermatitis, general physical deterioration, irregular heart rate, malaise, and small intestinal perforation. No deaths occurred from treatment-related causes. Interpretation To our knowledge, MEK162 is the first targeted therapy to show activity in patients with NRAS -mutated melanoma and might offer a new option for a cancer with few effective treatments. Funding Novartis Pharmaceuticals.
A multicenter, randomized phase II trial, RECORD-3, was conducted to compare first-line everolimus followed by sunitinib at progression with the standard sequence of first-line sunitinib followed by ...everolimus in patients with metastatic renal cell carcinoma.
RECORD-3 used a crossover treatment design. The primary objective was to assess progression-free survival (PFS) noninferiority of first-line everolimus compared with first-line sunitinib. Secondary end points included combined PFS for each sequence, overall survival (OS), and safety.
Of 471 enrolled patients, 238 were randomly assigned to first-line everolimus followed by sunitinib, and 233 were randomly assigned to first-line sunitinib followed by everolimus. The primary end point was not met; the median PFS was 7.9 months for first-line everolimus and 10.7 months for first-line sunitinib (hazard ratio HR, 1.4; 95% CI, 1.2 to 1.8). Among patients who discontinued first-line, 108 (45%) crossed over from everolimus to second-line sunitinib, and 99 (43%) crossed over from sunitinib to second-line everolimus. The median combined PFS was 21.1 months for sequential everolimus then sunitinib and was 25.8 months for sequential sunitinib then everolimus (HR, 1.3; 95% CI, 0.9 to 1.7). The median OS was 22.4 months for sequential everolimus and then sunitinib and 32.0 months for sequential sunitinib and then everolimus (HR, 1.2; 95% CI, 0.9 to 1.6). Common treatment-emergent adverse events during first-line everolimus or sunitinib were stomatitis (53% and 57%, respectively), fatigue (45% and 51%, respectively), and diarrhea (38% and 57%, respectively).
Everolimus did not demonstrate noninferiority compared with sunitinib as a first-line therapy. The trial results support the standard treatment paradigm of first-line sunitinib followed by everolimus at progression.
Postmenopausal breast cancer (BC) patients receiving adjuvant aromatase inhibitor therapy are at risk of progressive bone loss and fractures. Zoledronic acid inhibits osteoclastic bone resorption, is ...effective in maintaining bone health, and may therefore be beneficial in this setting.
Overall, 602 postmenopausal women with early, hormone receptor-positive BC receiving adjuvant letrozole were randomized (301 each group) to receive upfront or delayed-start zoledronic acid (4 mg intravenously every 6 months) for 5 years. The primary endpoint was the change in lumbar spine (LS) bone mineral density (BMD) at month 12. Secondary endpoints included changes in LS BMD, total hip BMD, and bone turnover markers at 2, 3, and 5 years; fracture incidence at 3 years; and time to disease recurrence.
At month 61, the adjusted mean difference in LS and total hip BMDs between the upfront and delayed groups was 8.9% and 6.7%, respectively (P < .0001, for both). Approximately 25% of delayed patients received zoledronic acid by month 61. Only 1 patient experienced grade 4 renal dysfunction; no confirmed cases of osteonecrosis of the jaw were reported. Fracture rates (upfront, 28 9.3%; delayed, 33 11%; P = .3803) and Kaplan-Meier disease recurrence rates (upfront, 9.8 95% confidence interval (CI), 6.0-10.3; delayed, 10.5 95% CI, 6.6-14.4; P = .6283) were similar at month 61.
Upfront zoledronic acid seems to be the preferred treatment strategy versus delayed administration, as it significantly and progressively increases BMD in postmenopausal women with early BC receiving letrozole for 5 years, and long-term coadministration of letrozole and zoledronic acid is well tolerated.
This phase II study determined the efficacy of lacnotuzumab added to gemcitabine plus carboplatin (gem-carbo) in patients with advanced triple-negative breast cancer (TNBC).
Female patients with ...advanced TNBC, with high levels of tumor-associated macrophages not amenable to curative treatment by surgery or radiotherapy were enrolled. Lacnotuzumab was dosed at 10 mg/kg every 3 weeks, ± a dose on cycle 1, day 8. Gemcitabine (1,000 mg/m
) and carboplatin (dose in mg calculated by area under the curve mg/mL/min × (glomerular filtration rate mL/min + 25 mL/min) were dosed every 3 weeks. Treatment continued until unacceptable toxicity, disease progression, or discontinuation by physician/patient.
Patients received lacnotuzumab + gem-carbo (
= 34) or gem-carbo (
= 15). Enrollment was halted due to recruitment challenges owing to rapid evolution of the therapeutic landscape; formal hypothesis testing of the primary endpoint was therefore not performed. Median progression-free survival was 5.6 months 90% confidence interval (CI), 4.47-8.64 in the lacnotuzumab + gem-carbo arm and 5.5 months (90% CI, 3.45-7.46) in the gem-carbo arm. Hematologic adverse events were common in both treatment arms; however, patients treated with lacnotuzumab experienced more frequent aspartate aminotransferase, alanine aminotransferase, and creatine kinase elevations. Pharmacokinetic results showed that free lacnotuzumab at 10 mg/kg exhibited a typical IgG pharmacokinetic profile and target engagement of circulating colony-stimulating factor 1 ligand.
Despite successful target engagement and anticipated pharmacokinetic profile, lacnotuzumab + gem-carbo showed comparable antitumor activity to gem-carbo alone, with slightly poorer tolerability. However, the data presented in this article would be informative for future studies testing agents targeting the CSF1-CSF1 receptor pathway in TNBC.
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