Systemic therapies for metastatic renal cell carcinoma in older adults

Is It Time to Integrate Frailty Assessment in Onconephrology?

Simple Summary

There are an increasing number of older people living with kidney cancer and/or cancer and kidney disease worldwide, sparking a wider discussion on the impact of frailty and the clinical significance of conducting frailty assessments for this patient population. We provide an update on the current evidence related to frailty assessment in onconephrology and identify areas where further research efforts are anticipated to address knowledge gaps within this topic.

Abstract

Onconephrology has emerged as a novel sub-specialty of nephrology dedicated to the intersection between the kidney and cancer. This intersection is broad and includes a number of important areas of focus, including concurrent chronic kidney disease (CKD) and cancer, acute kidney complications of cancer, and cancer-treatment-induced nephrotoxicity. The importance of onconephrology is even more evident when considering the global growth in the population of older adults, many of whom are living with some degree of frailty. Furthermore, a considerable proportion of older adults have CKD (some of whom eventually progress to kidney failure) and are at high risk of developing solid tumour and hematologic malignancies. Specific to kidney disease, the association between frailty status and kidney disease has been explored in depth, and tools to capture frailty can be used to guide the management and prognostication of older adults living with kidney failure. Whilst there is emerging data regarding the assessment and impact of frailty in onconephrology, there remains a relative paucity of knowledge within this topic. In this article, we evaluate the definition and operationalization of frailty and discuss the significance of frailty within onconephrology. We review evidence on current approaches to assessing frailty in onconephrology and discuss potential developments and future directions regarding the utilization of frailty in this patient population. A greater awareness of the intersections and interactions between frailty and onconephrology and further efforts to integrate frailty assessment in onconephrology to optimize the delivery of realistic and goal-directed management strategies for patients is needed.

Real-World Outcomes Among US Veterans Health Administration Patients Newly Diagnosed with Metastatic Renal Cell Carcinoma and Treated with First-Line Monotherapy

INTRODUCTION

Substantial unmet needs exist among patients with metastatic renal cell carcinoma (mRCC). This retrospective study evaluated treatment patterns as well as clinical and economic outcomes associated with first-line monotherapy among patients with mRCC in the USA.

METHODS

Newly diagnosed patients with mRCC initiating at least one first-line therapy (1L) from 1 October 2013 to 31 March 2018 (index date = 1L start date) were identified from the US Veterans Health Administration database. Treatment patterns, clinical outcomes (time to next treatment [TNT] defined by earliest of switch to non-index therapy or re-initiation of index therapy after a more than 90-day gap, time to treatment discontinuation [TTD], overall survival [OS]), and costs were evaluated among patients treated with tyrosine kinase inhibitors (TKI), mammalian target of rapamycin inhibitors (mTOR), immune checkpoint inhibitors (ICI), and other monotherapies. Standard descriptive statistics were presented. The Kaplan-Meier method was used to evaluate clinical outcomes.

RESULTS

Of 759 patients (median age 68.0 years), 85.0%, 8.0%, 4.3%, and 2.6% were treated with TKI, mTOR, ICI, or other therapy in 1L, respectively. Advancement rates (to second-line [2L] therapy) ranged from 10.0 (ICI) to 45.1 per 100 person years (TKI). The 12-month OS rates ranged from 47.4% (TKI) to 67.7% (mTOR). The median TNT ranged from 3.8 (mTOR) to 9.6 months (ICI), and median TTD ranged from 2.3 (mTOR) to 4.7 months (TKI). Total all-cause mean costs per patient per month ranged from $12,466 (mTOR) to $19,812 (ICI).

CONCLUSION

These results indicate high unmet medical needs among patients with mRCC treated with 1L monotherapies. Novel combination therapies (e.g., ICI + ICI, ICI + TKI) may improve front-line outcomes for patients with poor prognoses.

Outcomes based on age in patients with metastatic renal cell carcinoma treated with first line targeted therapy or checkpoint immunotherapy: Older patients more prone to toxicity

OBJECTIVES

Older patients with metastatic renal cell carcinoma (mRCC) were underrepresented in pivotal trials.

MATERIALS AND METHODS

Consecutive patients with mRCC treated at Aarhus University Hospital with first line tyrosine kinase inhibitors (TKI), mTOR inhibitors, or checkpoint immunotherapy (CPI) were retrospectively analyzed in age-subgroups; ≥ 75, 65-74, and < 65 years, with overall survival (OS), time-to-treatment discontinuation (TTD), and progression-free survival (PFS) as endpoints. Hazards ratios were adjusted (aHR) for International Metastatic RCC Database Consortium (IMDC) risk factors, histology, and age.

RESULTS

Of 838 patients, 159 (19%) were ≥ 75 years, 324 (39%) 65-74 years, and 355 (42%) < 65 years. Treatments were TKI in 729 (87%) patients, mTOR in 43 (5%) and CPI in 67 (8%). Older patients ≥ 75 years compared with 65-74 years and < 65 years had lower toxicity-adjusted median doses of pazopanib, 300 mg vs. 400 mg vs. 600 mg, respectively, (p < 0.001), and sunitinib, 25 mg vs. 37.5 mg vs. 50 mg, respectively (p < 0.001); numerically fewer doses of CPI, median 2 vs. 5 vs. 5, respectively, (p = 0.2); a higher proportion had dose reduction/interruption, 76% vs. 55% vs. 41%, respectively, (p < 0.001); and shorter mean time to dose reduction/interruption, 0.5 months vs. 1.9 months vs. 3.4 months, respectively, (p < 0.001). After adjusting IMDC prognostic factors and histology in multivariate analyses, age did not impact OS (aHR 1.0; 95% CI 0.99-1.02, p = 0.2), TTD (aHR 1.0; 95% CI 0.99-1.01, p = 0.4) or PFS (aHR 1.0, 95% CI 0.99-1.01; p = 0.9).

CONCLUSION

Older patients with mRCC were more prone to toxicity; but age did not impact outcomes. Proactive dose modification/interruption and awareness may help to reduce toxicity while maintaining efficacy.

Improved prognosis for elderly patients with metastatic renal cell carcinoma in the era of targeted therapy

The present study investigated the outcomes of targeted therapy for elderly patients with metastatic renal cell carcinoma (mRCC). A total of 277 patients with mRCC who were treated with tyrosine kinase inhibitor as a first-line therapy from January 2008 to May 2018 were retrospectively investigated by reviewing clinicopathological data. Patients 75 years or older were classified into the older-aged group (n=55) while all others were classified into the younger-aged group (n=222). The preoperative clinicopathological characteristics and the overall survival (OS) rate for these two groups were subsequently compared. The median age in the older- and younger-aged groups was 78 and 63 years (P<0.0001), respectively. A total of 7, 42 and 6 cases in the older-aged group and 46, 118 and 58 cases in the younger-aged group were classified into favorable, intermediate, and poor risk groups, respectively. The rate of patients with cardiovascular diseases (29.1%) and malignant diseases other than RCC (20.0%) was significantly higher in the older-aged group compared with the younger-aged group (6.8%; P<0.0001 and 7.2%; P=0.0042, respectively). There was a significant improvement in the OS rate for patients beginning targeted therapy after 2011 compared with those starting therapy prior to 2010. The 50% OS rate in patients starting targeted therapy before 2010 and after 2011 was, respectively, 17.1 and 38.6 months for the older-aged group (P=0.0066), while there was no significant difference for the younger-aged group (P=0.1441; 50% OS; 35.9 vs. 30.5 months). The results of the present study indicated that the prognosis for older patients has improved since the introduction of targeted therapy.

Outcomes based on age in the phase III METEOR trial of cabozantinib versus everolimus in patients with advanced renal cell carcinoma

Background

Cabozantinib improved progression-free survival (PFS), overall survival (OS) and objective response rate (ORR) compared with everolimus in patients with advanced renal cell carcinoma (RCC) after prior antiangiogenic therapy in the phase III METEOR trial (NCT01865747). Limited data are available on the use of targeted therapies in older patients with advanced RCC.

Methods

Efficacy and safety in METEOR were retrospectively analysed for three age subgroups: <65 (n = 394), 65–74 (n = 201) and ≥75 years (n = 63).

Results

PFS, OS and ORR were improved with cabozantinib compared with everolimus in all age subgroups. The PFS hazard ratios (HRs) were 0.53 (95% confidence interval [CI]: 0.41–0.68), 0.53 (95% CI: 0.37–0.77) and 0.38 (95% CI: 0.18–0.79) for <65, 65–74 and ≥75 years, respectively, and the OS HRs were 0.72 (95% CI: 0.54–0.95), 0.66 (95% CI: 0.44–0.99) and 0.57 (95% CI: 0.28–1.14). The ORR for cabozantinib versus everolimus was 15% vs 5%, 21% vs 2% and 19% vs 0%, respectively. No significant differences were observed in PFS or OS with age as a categorical or continuous variable. Grade III/IV adverse events (AEs) were generally consistent across subgroups, although fatigue, hypertension and hyponatraemia occurred more frequently in older patients treated with cabozantinib. Dose reductions to manage AEs were more frequent in patients receiving cabozantinib than in those receiving everolimus. Dose reductions and treatment discontinuation due to AEs were more frequent in older patients in both treatment groups.

Conclusions

Cabozantinib improved PFS, OS and ORR compared with everolimus in previously treated patients with advanced RCC, irrespective of age group, supporting use in all age categories. Proactive dose modification and supportive care may help to mitigate AEs in older patients while maintaining efficacy.

Current systemic therapies for metastatic renal cell carcinoma in older adults: A comprehensive review

Physiological changes that occur during the aging process may impact drug metabolism and availability, consequently affecting treatment efficacy and tolerability. Despite being a disease of older adults, there is little data to guide treatment decisions for older patients with metastatic renal cell carcinoma (mRCC). The recent approval of many new agents for this disease poses a clinical challenge: how to best utilize these drugs in a population (older adults) who has been generally under-represented in clinical studies. Additionally, the presence of comorbid conditions, polypharmacy, frailty, and lack of social support place this group of patients in a very unique situation. In order to avoid under-treatment, international societies' guidelines recommend routine use of geriatric tools to assess patients' suitability for systemic treatments. Here we provide a thorough review of age-related metabolic differences, safety and efficacy data for each drug approved for mRCC, and cover specific considerations for the management of older adults with this disease.

Efficacy and safety of axitinib in elderly patients with metastatic renal cell carcinoma

The objective of this study was to analyze the impact of age on clinical outcomes of metastatic renal cell carcinoma (mRCC) patients receiving axitinib. This study included 144 consecutive mRCC patients who received axitinib for at least 12 weeks as second-line therapy in a routine clinical setting. The efficacy, safety and quality of life (QOL) were compared between patients aged <75 (n = 116) and ≥75 (n = 28) years. No significant differences in the clinicopathological characteristics were noted between younger and older patients. There was no significant difference in the response rate, clinical benefit rate or proportion of patients going on to receive third-line therapy between these two groups. In addition, the progression-free and overall survivals in older patients were similar to those in younger patients. There were no significant differences in the incidences of adverse events between these two groups, except for that of fatigue, which was significantly more frequent in older than younger patients. There was no significant difference in the incidence of the discontinuation of axitinib due to adverse events between the two groups. QOL assessment at 12 weeks after the introduction of axitinib using the Medical Outcomes Study 36-Item Short Form showed no significant differences in any of the eight scale scores between the two groups. Taken together, it might be possible to achieve clinical outcomes in older patients receiving axitinib comparable to those in younger patients, suggesting that advanced age should not be a contraindication to treatment with axitinib as a second-line setting in mRCC patients.

Weekly nab-Rapamycin in patients with advanced nonhematologic malignancies: final results of a phase I trial

PURPOSE

This dose-finding phase I study investigated the maximum-tolerated dose (MTD) and safety of weekly nanoparticle albumin-bound rapamycin (nab-rapamycin) in patients with untreatable advanced nonhematologic malignancies.

EXPERIMENTAL DESIGN

nab-Rapamycin was administered weekly for 3 weeks followed by 1 week of rest, with a starting dose of 45 mg/m(2). Additional doses were 56.25, 100, 150, and 125 mg/m(2).

RESULTS

Of 27 enrolled patients, 26 were treated. Two dose-limiting toxicities (DLT) occurred at 150 mg/m(2) [grade 3 aspartate aminotransferase (AST) elevation and grade 4 thrombocytopenia], and two DLTs occurred at 125 mg/m(2) (grade 3 suicidal ideation and grade 3 hypophosphatemia). Thus, the MTD was declared at 100 mg/m(2). Most treatment-related adverse events (TRAE) were grade 1/2, including thrombocytopenia (58%), hypokalemia (23%), mucositis (38%), fatigue (27%), rash (23%), diarrhea (23%), nausea (19%), anemia (19%), hypophosphatemia (19%), neutropenia (15%), and hypertriglyceridemia (15%). Only one grade 3 nonhematologic TRAE (dyspnea) and one grade 3 hematologic event (anemia) occurred at the MTD. One patient with kidney cancer had a partial response and 2 patients remained on study for 365 days (patient with mesothelioma) and 238 days (patient with neuroendocrine tumor). The peak concentration (Cmax) and area under the concentration-time curve (AUC) of rapamycin increased with dose between 45 and 150 mg/m(2), except for a relatively low AUC at 125 mg/m(2). nab-Rapamycin significantly inhibited mTOR targets S6K and 4EBP1.

CONCLUSIONS

The clinical dose of single-agent nab-rapamycin was established at 100 mg/m(2) weekly (3 of 4 weeks) given intravenously, which was well tolerated with preliminary evidence of response and stable disease, and produced a fairly dose-proportional pharmacokinetic profile in patients with unresectable advanced nonhematologic malignancies.

Efficacy and safety of sunitinib in elderly patients with metastatic renal cell carcinoma

Background:

We retrospectively analyzed sunitinib outcome as a function of age in metastatic renal cell carcinoma (mRCC) patients.

Methods:

Data were pooled from 1059 patients in six trials. Kaplan–Meier estimates of progression-free survival (PFS) and overall survival (OS) were compared by log-rank test between patients aged <70 (n=857; 81%) and ⩾70 (n=202; 19%) years.

Results:

In first-line patients, median PFS was comparable in younger and older patients, 9.9 vs 11.0 months, respectively (HR, 0.89; 95% CI: 0.73–1.09; P=0.2629), as was median OS, 23.6 vs 25.6 months (HR, 0.93; 95% CI: 0.74–1.18; P=0.5442). Similarly, in cytokine-refractory patients, median PFS was 8.1 vs 8.4 months (HR, 0.79; 95% CI: 0.49–1.28; P=0.3350), while median OS was 20.2 vs 15.8 months (HR, 1.14; 95% CI: 0.73–1.79; P=0.5657). Some treatment-emergent adverse events were significantly less common in younger vs older patients, including fatigue (60% vs 69%), cough (20% vs 29%), peripheral edema (17% vs 27%), anemia (18% vs 25%), decreased appetite (13% vs 29%), and thrombocytopenia (16% vs 25% all P<0.05). Hand–foot syndrome was more common in younger patients (32% vs 24%).

Conclusions:

Advanced age should not be a deterrent to sunitinib therapy and elderly patients may achieve additional clinical benefit.

Impact of age on treatment trends and clinical outcome in patients with metastatic renal cell carcinoma

OBJECTIVES

Clinical outcomes in older adults with metastatic renal cell carcinoma (mRCC) are poorly understood, particularly in the era of targeted therapies. We characterize survival and relevant treatment-related variables in a modern series.

MATERIALS AND METHODS

From an institutional database including 562 patients with RCC, a total of 219 patients with metastatic disease were identified for the current analysis. Survival was assessed in four age-based cohorts: (1) age<55, (2) age 55–64, (3) age 65–74, and(4) age≥75. The number of lines of therapy rendered was collected for each patient, and the reason for treatment discontinuation was characterized.

RESULTS

Of the 219 patients assessed, median age was 58 (range, 26–87), and most patients had clear cell histology (82%) and prior nephrectomy (70.9%). The majority of patients were characterized as intermediate-risk (53%) by MSKCC criteria. Median survival in patients age≥75 was 12.5 months, as compared to 26.4 months for patients age<75 (P=0.003). Patients age≥75 received fewer lines of systemic therapy as compared to other age-based subsets, and more frequently discontinued therapies due to toxicity.

CONCLUSIONS

Older adults represent a unique subpopulation of patients with mRCC, with distinct clinical outcomes. Further research is warranted to better understand the safety and tolerability of current therapies for mRCC in this group.