Adverse event management in patients with advanced cancer receiving oral everolimus: focus on breast cancer

Combination of everolimus with trastuzumab plus paclitaxel as first-line treatment for patients with HER2-positive advanced breast cancer (BOLERO-1): a phase 3, randomised, double-blind, multicentre trial

BACKGROUND

mTOR inhibition reverses trastuzumab resistance via the hyperactivated PIK/AKT/mTOR pathway due to PTEN loss, by sensitising PTEN-deficient tumours to trastuzumab. The BOLERO-1 study assessed the efficacy and safety of adding everolimus to trastuzumab and paclitaxel as first-line treatment for patients with HER2-positive advanced breast cancer.

METHODS

In this phase 3, randomised, double-blind trial, patients were enrolled across 141 sites in 28 countries. Eligible patients were aged 18 years or older, with locally assessed HER2-positive advanced breast cancer, with Eastern Cooperative Oncology Group (ECOG) performance status of 0-1, who had not received previous trastuzumab or chemotherapy for advanced breast cancer within 12 months of randomisation, had measurable disease as per Response Evaluation Criteria in Solid Tumors (RECIST) or bone lesions in the absence of measurable disease, without previous systemic treatment for advanced disease except endocrine therapy. Patients were randomly assigned (2:1) with an interactive voice and web response system to receive either 10 mg everolimus once a day orally or placebo plus weekly trastuzumab intravenously at 4 mg/kg loading dose on day 1 with subsequent weekly doses of 2 mg/kg of each 4 week cycle plus paclitaxel intravenously at a dose of 80 mg/m(2) on days 1, 8, and 15 of each 4 week cycle. Randomisation was stratified according to previous use of trastuzumab and visceral metastasis. Patients and investigators were masked to the assigned treatments. Identity of experimental treatments was concealed by use of everolimus and placebo that were identical in packaging, labelling, appearance, and administration schedule. The two primary objectives were investigator-assessed progression-free survival in the full study population and in the subset of patients with hormone receptor-negative breast cancer at baseline; the latter was added during the course of the study, before unmasking based on new clinical and biological findings from other studies. All efficacy analyses were based on the intention-to-treat population. Enrolment for this trial is closed and results of the final progression-free survival analyses are presented here. This trial is registered with ClinicalTrials.gov, number NCT00876395.

FINDINGS

Between Sept 10, 2009, and Dec 16, 2012, 719 patients were randomly assigned to receive everolimus (n=480) or placebo (n=239). Median follow-up was 41·3 months (IQR 35·4-46·6). In the full population, median progression-free survival was 14·95 months (95% CI 14·55-17·91) with everolimus versus 14·49 months (12·29-17·08) with placebo (hazard ratio 0·89, 95% CI 0·73-1·08; p=0·1166). In the HR-negative subpopulation (n=311), median progression-free survival with everolimus was 20·27 months (95% CI 14·95-24·08) versus 13·08 months (10·05-16·56) with placebo (hazard ratio 0·66, 95% CI 0·48-0·91; p=0·0049); however, the protocol-specified significance threshold (p=0·0044) was not crossed. The most common adverse events with everolimus were stomatitis (314 [67%] of 472 patients in the everolimus group vs 77 [32%] of 238 patients in the placebo group), diarrhoea (267 [57%] vs 111 [47%] patients), and alopecia (221 [47%] vs 125 [53%]). The most frequently reported grade 3 or 4 adverse events in the everolimus group versus the placebo group were neutropenia (117 [25%] vs 35 [15%]), stomatitis (59 [13%] vs three [1%]), anaemia (46 [10%] vs six [3%]) and diarrhoea (43 [9%] vs 10 [4%]) On-treatment adverse event-related deaths were reported in 17 (4%) patients in the everolimus group and none in the placebo group.

INTERPRETATION

Although progression-free survival was not significantly different between groups in the full analysis population, the 7·2 months prolongation we noted with the addition of everolimus in the HR-negative, HER2-positive population warrants further investigation, even if it did not meet prespecified criteria for significance. The safety profile was generally consistent with what was previously reported in BOLERO-3. Proactive monitoring and early management of adverse events in patients given everolimus and chemotherapy is crucial.

FUNDING

Novartis Pharmaceuticals.

Renal effects of targeted anticancer therapies

The use of novel targeted anticancer agents has led to overall improvement in the prognosis of many patients affected by various malignancies, but has also been associated with an increased risk of poorly characterized toxic effects to different organs, including the kidneys. The high prevalence of kidney impairment in the general population complicates the issue further. Nephrologists most frequently work with patients with cancer when they are asked to investigate kidney function to assess the need for dose adjustments in anticancer therapy. A thorough knowledge of the renal safety profile of novel life-prolonging anticancer therapies, specific features of their metabolism, and pharmacokinetic and pharmacodynamic properties (under normal circumstances as well as in the setting of renal replacement therapy) is, therefore, necessary to preserve kidney function as far as possible and to ensure optimum treatment. In this Review we summarize the present knowledge of renal toxic effects from novel targeted anticancer agents and discuss whether the management of patients' treatment needs to be modified. We also advocate the development of a new onconephrology subspeciality.

Systemic treatment approaches in her2-negative advanced breast cancer-guidance on the guidelines

Despite advancements in the treatment of early-stage breast cancer, many patients still develop disease recurrence; others present with de novo metastatic disease. For most patients with advanced breast cancer, the primary treatment intent is noncurative-that is, palliative-in nature. The goals of treatment should therefore focus on maximizing symptom control and extending survival. Treatments should be evaluated on an individualized basis in terms of evidence, but also with full respect for the wishes of the patient in terms of acceptable toxicity. Given the availability of extensive reviews on the roles of endocrine therapy and her2 (human epidermal growth factor receptor 2)-targeted therapies for advanced disease, we focus here mainly on treatment guidelines for the non-endocrine management of her2-negative advanced breast cancer in a Canadian health care context.

Novel agents and associated toxicities of inhibitors of the pi3k/Akt/mtor pathway for the treatment of breast cancer

The pi3k/Akt/mtor (phosphatidylinositol 3 kinase/ Akt/mammalian target of rapamycin) signalling pathway is an established driver of oncogenic activity in human malignancies. Therapeutic targeting of this pathway holds significant promise as a treatment strategy. Everolimus, an mtor inhibitor, is the first of this class of agents approved for the treatment of hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer. Everolimus has been associated with significant improvements in progression-free survival; however, it is also associated with increased toxicity related to its specific mechanism of action.

METHODS

A comprehensive review of the literature conducted using a focused medline search was combined with a search of current trials at http://ClinicalTrials.gov/. Summary tables of the toxicities of the various classes of pi3k/Akt/mtor inhibitors were created. A broad group of Canadian health care professionals was assembled to review the data and to produce expert opinion and summary recommendations for possible best practices in managing the adverse events associated with these pathway inhibitors.

RESULTS

Differing toxicities are associated with the various classes of pi3k/Akt/mtor pathway inhibitors. The most common unique adverse events observed in everolimus clinical trials in breast cancer include stomatitis (all grades: approximately 60%), noninfectious pneumonitis (15%), rash (40%), hyperglycemia (15%), and immunosuppression (40%). To minimize grades 3 and 4 toxicities and to attempt to attain optimal outcomes, effective management of those adverse events is critical. Management should be interdisciplinary and should use approaches that include education, early recognition, active intervention, and potentially prophylactic strategies.

DISCUSSION

Everolimus likely represents the first of many complex oral targeted therapies for the treatment of breast cancer. Using this agent as a template, it is essential to establish best practices involving and integrating multiple disciplines for the management of future pi3k/Akt/mtor signalling pathway inhibitors.

Cost of adverse events during treatment with everolimus plus exemestane or single-agent chemotherapy in patients with advanced breast cancer in Western Europe

OBJECTIVE

Treatment options for recurrent or progressive hormone receptor-positive (HR+) advanced breast cancer include chemotherapy and everolimus plus exemestane (EVE + EXE). This study estimates the costs of managing adverse events (AEs) during EVE + EXE therapy and single-agent chemotherapy in Western Europe.

METHODS

An economic model was developed to estimate the per patient cost of managing grade 3/4 AEs for patients who were treated with EVE + EXE or chemotherapies. AE rates for patients receiving EVE + EXE were collected from the phase III BOLERO-2 trial. AE rates for single-agent chemotherapy, capecitabine, docetaxel, or doxorubicin were collected from published clinical trial data. AEs with at least 2% prevalence for any of the treatments were included in the model. A literature search was conducted to obtain costs of managing each AE, which were then averaged across Western European countries (when available). Per patient costs for managing AEs among patients receiving different therapies were reported in 2012 euros (€).

RESULTS

The EVE + EXE combination had the lowest average per patient cost of managing AEs (€730) compared to all chemotherapies during the first year of treatment (doxorubicin: €1230; capecitabine: €1721; docetaxel: €2390). The most costly adverse event among all patients treated with EVE + EXE was anemia (on average €152 per patient). The most costly adverse event among all patients treated with capecitabine, docetaxel, or doxorubicin was lymphocytopenia (€861 per patient), neutropenia (€821 per patient), and leukopenia (€382 per patient), respectively.

CONCLUSIONS

The current model estimates that AE management during the treatment of HR+ advanced breast cancer will cost one-half to one-third less for EVE + EXE patients than for chemotherapy patients. The consideration of AE costs could have important implications in the context of healthcare spending for advanced breast cancer treatment.

Adverse event management of oral mucositis in patients with breast cancer

Oral mucositis (OM) is a clinically important and frequent adverse event (AE) associated with cancer treatment with conventional chemotherapy as well as new targeted agents. Incidence and severity of OM vary from treatment to treatment and from patient to patient. The pathogenesis of chemotherapy-induced OM can be divided into 5 phases. OM induced by targeted therapies differs among other things in appearance, course, concomitant AEs and toxicity, and thus could be perceived as an entity distinct from chemotherapy-induced OM with an innate pathogenic mechanism. OM has a severe impact on a patient's quality of life (QoL) by causing complications such as pain and discomfort. Even more important are associated restrictions in nutrition and hydration. Thus, the efficacy of cancer therapy might be impaired due to the necessity of dose delays and dose reductions. Numerous preventive and therapeutic approaches have been evaluated, but currently no single agent has changed the standard of care in preventing and treating OM. Thus, the current management has evolved from clinical experience rather than clinical evidence. This article will review the AE 'OM' induced by breast cancer treatment with chemotherapy and targeted agents in order to provide practical guidance for management and prevention.

Development of protocol for the management of cervical cancer symptoms in resource-constrained developing countries

Cervical cancer is the commonest malignancy of women in economically emerging countries. Patients have distressing symptoms from presentation through follow-up or end of life. Cervical cancer imposes significant burden on health care system due to distressing symptoms and associated loss of quality-adjusted life years (QALY). Multitude of drugs and surgical measures in various combinations can relieve these distressing symptoms and various clinical conditions. The protocols and guidelines for alleviation or relief of symptoms by general pharmacological and surgical measures form an important policy subject in planning cervical cancer management program. These protocol and guidelines are based on the mechanism of action of drugs, extrapolation from management of similar symptoms, and clinical situations arising out of other non-cancerous conditions and experience of health care professionals. Therefore, rigorous evaluation of effectiveness of supportive health care services in developing countries is the need of hour. However, evaluation of such protocol and guidelines are not feasible in emerging economies due to resource constraint. Industrialized affluent nations are also not able to implement and further support care guidelines despite its recognition as an integral part of multidisciplinary management of cancer. Aforementioned factors have created blind spot zone of management purview of cervical cancer. Hence, we attempt to develop protocol for management of adverse events of cervical cancer. Symptoms' and medical conditions' management guidelines evolved on the basis of empirical clinical practice in community and premier oncology centers in resource-constrained developing countries has been presented in this short report. This report should not be an end in itself but has to attract attention of policy-makers, academicians, researchers, and practitioners toward advancing supportive care needs of cancer patients in low- and middle-income countries (LMIC).

mTOR inhibitor-associated stomatitis (mIAS) in three patients with cancer treated with everolimus

Mammalian targets of rapamycin inhibitors (mTOR inhibitors, mTORI) are indicated for the management of several cancer types, including hormone receptor--positive or HER2-negative breast cancer, advanced renal cell carcinoma, advanced neuroendocrine tumors of pancreatic origin, and tuberous sclerosis complex-related tumors. Among the most common adverse events of mTORI medication are discrete, large, solitary or multiple, superficial ulcers, almost exclusively situated on nonkeratinized oral mucosa, described as mTORI-associated stomatitis (mIAS). We describe the clinical presentation, course, and management of mIAS in three patients receiving the mTORI everolimus (Afinitor, Novartis, East Hanover, NJ). In two patients, mIAS manifested 9 and 30 days after first using everolimus, respectively, whereas in the third patient, it recurred 3 months after re-introduction of everolimus. Oral rinses with a "magic mouthwash" solution (dexamethasone oral drops solution 2 mg/mL × 10 mL, lidocaine gel 2% × 30 g, doxycycline suspension 50 mg/5 mL × 60 mL, and sucralfate oral suspension 1000 mg/5 mL × 150 mL, dissolved in sodium chloride 0.9% × 2000 mL) four times daily proved helpful in alleviating the symptoms, and the ulcers healed in 4 to 15 days. No side effects were recorded, and dose reduction or discontinuation of everolimus was not necessitated in two cases.