Phase II Study of Two Weeks on, One Week off Sunitinib Scheduling in Patients With Metastatic Renal Cell Carcinoma

Purpose Standard frontline treatment of patients with metastatic renal cell carcinoma currently includes sunitinib. A barrier to long-term treatment with sunitinib includes the development of significant adverse effects, including diarrhea, hand-foot syndrome (HFS), and fatigue. This trial assessed the effect of an alternate 2 weeks on, 1 week off (2/1) schedule of sunitinib on toxicity and efficacy in previously untreated patients with metastatic renal cell carcinoma. Methods Patients started with oral administration of 50 mg sunitinib on a 2/1 schedule and underwent schedule and dose alterations if toxicity developed. The primary end point was < 15% grade ≥ 3 fatigue, diarrhea, or HFS. With 60 patients, the upper bound of the CI would fall below the published 4/2 schedule grade ≥ 3 toxicity rate of 25% to 30%. Results Fifty-nine patients were treated between August 2014 and March 2016. Seventy-seven percent were intermediate or poor risk per Memorial Sloan Kettering Cancer Center criteria. With a median follow-up of 17 months, 25% of patients experienced grade 3 fatigue, HFS, or diarrhea; 37% required a dose reduction, and 10% discontinued because of toxicity. The overall response rate was 57%, median progression-free survival was 13.7 months, and median overall survival was not reached. At 12 weeks, Functional Assessment of Cancer Therapy-General scores dropped between 0% and 10% from baseline, with less reduction in patients who continued treatment longer. Conclusion The primary end point of decreased grade 3 toxicity was not met; however, treatment with a 2/1 sunitinib schedule is associated with a lack of grade 4 toxicity, a low patient discontinuation rate, and high efficacy.

Phase II study of alternate sunitinib schedule in patients with metastatic renal cell carinoma

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Background: Sunitinib is an antiangiogenic agent indicated for the treatment of metastatic renal cell carcinoma (mRCC). Sunitinib is given in a 4 week on, 2 week off (4/2) schedule. Significant toxicities are observed in patients in the 3rd and 4th weeks of therapy. We hypothesized that a 2 week on, 1 week off (2/1) schedule would provide improved toxicity without compromising efficacy. Methods: A multicenter, single arm study was performed, with patients initiating sunitinib 50mg on a 2/1 schedule. Schedule and dose alterations were performed if grade > 3 toxicities were observed. The primary objective was to determine the percentage of patients who experienced grade > 3 fatigue, diarrhea, or HFS. The sample size of 60 patients was selected to ensure the upper bound of a 95% confidence would fall below standard schedule rate of 25%-30% if sample rate was 10%-15%, respectively. Secondary outcomes included response rate (RR), progression free survival (PFS) and dose reductions. Results: Between August 2014 and April 2016, 60 patients were enrolled, and 59 treated. Patients had a median age of 65.5 years (ranging from 45-92). 24% of patients (14/59) had grade 3 or higher fatigue, diarrhea, or HFS (95% CI: 13.6%, 36.6%). This is similar to the average of the 4 week on, 2 week off schedule of 25%-30%, and the lower bound of the confidence interval is in the center of our target rate of 10%-15%. Among events at least possibly related to study drug, patients were most likely to experience the expected events of diarrhea (75% with 5 grade 3 events), fatigue (71% with 6 grade 3 events), and HFS (54% with 3 grade 3 events). 22 (37%) patients responded (25.0%, 50.9%). Among patients with secondary endpoint data available, median PFS was 19.3 months (95% CI: 8.2, NR) and 33/56 (59%) of patients underwent dose reduction. Conclusions: Sunitinib administered in a 2/1 schedule in this study did not result in a lower rate of grade 3 or higher fatigue, diarrhea or HFS when compared to historical data from trials employing a 4/2 schedule. However, efficacy data showed robust response rate and a prolonged PFS, suggestive of long-term tolerability in patients receiving sunitinib on a 2/1 schedule. Evaluation of toxicity kinetics and patient quality of life is ongoing. Clinical trial information: NCT02060370.

A randomized phase 2 study of MK-2206 versus everolimus in refractory renal cell carcinoma

Background

Activation of the phosphoinisitide-3 kinase (PI3K) pathway through mutation and constitutive upregulation has been described in renal cell carcinoma (RCC), making it an attractive target for therapeutic intervention. We performed a randomized phase II study in vascular endothelial growth factor (VEGF) therapy refractory patients to determine whether MK-2206, an allosteric inhibitor of AKT, was more efficacious than the mammalian target of rapamycin inhibitor everolimus.

Patients and methods

A total of 43 patients were randomized in a 2:1 distribution, with 29 patients assigned to the MK-2206 arm and 14 to the everolimus arm. Progression-free survival (PFS) was the primary endpoint.

Results

The trial was closed at the first futility analysis with an observed PFS of 3.68 months in the MK-2206 arm and 5.98 months in the everolimus arm. Dichotomous response rate profiles were seen in the MK-2206 arm with one complete response and three partial responses in the MK-2206 arm versus none in the everolimus arm. On the other hand, progressive disease was best response in 44.8% of MK2206 versus 14.3% of everolimus-treated patients. MK-2206 induced significantly more rash and pruritis than everolimus, and dose reduction occurred in 37.9% of MK-2206 versus 21.4% of everolimus-treated patients. Genomic analysis revealed that 57.1% of the patients in the PD group had either deleterious TP53 mutations or ATM mutations or deletions. In contrast, none of the patients in the non-PD group had TP53 or ATM defects. No predictive marker for response was observed in this small dataset.

Conclusions

Dichotomous outcomes are observed when VEGF therapy refractory patients are treated with MK-2206, and MK-2206 does not demonstrate superiority to everolimus. Additionally, mutations in DNA repair genes are associated with early disease progression, indicating that dysregulation of DNA repair is associated with a more aggressive tumor phenotype in RCC.

A phase II study of alternative sunitinib scheduling in patients with metastatic renal cell carcinoma

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Background: Sunitinib is an oral antiangiogenic agent indicated for the treatment of metastatic renal cell carcinoma (mRCC). Sunitinib is given in a 4 week on, 2 week off (4/2) schedule. Significant toxicities are observed in patients in the 3rd and 4thweeks of therapy. We hypothesized that a 2 week on, 1 week off (2/1) schedule would provide improved toxicity without compromising efficacy. Methods: A multicenter, single arm study was performed, with all patients initiating sunitinib 50mg on a 2/1 schedule. Schedule and dose alterations were performed if grade > 3 toxicities were observed. The primary objective was to determine the percentage of patients who experienced grade > 3 fatigue, diarrhea, or HFS. The sample size of 60 patients was selected to ensure that the upper bound of a 95% confidence would fall below the standard schedule rate of 25%-30% if the sample rate was 10%-15%, respectively. Secondary outcomes included response rate (RR), progression free survival (PFS), and dose reductions. Results: Between August 2014 and April 2016, a total of 60 patients were enrolled, and 59 were treated. Patients had a median age of 65.5 years (ranging from 45-92). 24% of patients (14/59) had grade 3 or higher fatigue, diarrhea, or HFS (95% CI: 13.6%, 36.6%). This is similar to the average of the 4 week on, 2 week off schedule of 25%-30%, and the lower bound of the confidence interval is in the center of our target rate of 10%-15%. Among events that are at least possibly related to study drug, patients were most likely to experience the expected events of diarrhea (75% with 5 grade 3 events), fatigue (71% with 6 grade 3 events), and HFS (54% with 3 grade 3 events). 22 (37%) patients responded (25.0%, 50.9%). Among patients with secondary endpoint data available, median PFS was 19.3 months (95% CI: 8.2, NR) and 33/56 (59%) of patients underwent dose reduction. Conclusions: Sunitinib administered in a 2/1 schedule in this study did not result in a lower rate of grade 3 or higher fatigue, diarrhea, or HFS when compared to historical data from trials employing a 4/2 schedule. Efficacy data were comparable to studies employing a 4/2 schedule. Clinical trial information: NCT02060370.