Efficacy and safety of palbociclib in combination with letrozole as first-line treatment of ER-positive, HER2-negative, advanced breast cancer: expanded analyses of subgroups from the randomized pivotal trial PALOMA-1/TRIO-18.

BACKGROUND: Palbociclib is an oral small-molecule inhibitor of cyclin-dependent kinases 4 and 6. In the randomized, open-label, phase II PALOMA-1/TRIO-18 trial, palbociclib in combination with letrozole improved progression-free survival (PFS) compared with letrozole alone as first-line treatment of estrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, advanced breast cancer (20.2 months versus 10.2 months; hazard ratio (HR) = 0.488, 95 % confidence interval (CI) 0.319-0.748; one-sided p = 0.0004). Grade 3-4 neutropenia was the most common adverse event (AE) in the palbociclib + letrozole arm. We now present efficacy and safety analyses based on several specific patient and tumor characteristics, and present in detail the clinical patterns of neutropenia observed in the palbociclib + letrozole arm of the overall safety population. METHODS: Postmenopausal women (n = 165) with ER+, HER2-negative, advanced breast cancer who had not received any systemic treatment for their advanced disease were randomized 1:1 to receive either palbociclib in combination with letrozole or letrozole alone. Treatment continued until disease progression, unacceptable toxicity, consent withdrawal, or death. The primary endpoint was PFS. We now analyze the difference in PFS for the treatment populations by subgroups, including age, histological type, history of prior neoadjuvant/adjuvant systemic treatment, and sites of distant metastasis, using the Kaplan-Meier method. HR and 95 % CI are derived from a Cox proportional hazards regression model. RESULTS: A clinically meaningful improvement in median PFS and clinical benefit response (CBR) rate was seen with palbociclib + letrozole in every subgroup evaluated. Grade 3-4 neutropenia was the most common AE with palbociclib + letrozole in all subgroups. Analysis of the frequency of neutropenia by grade during the first six cycles of treatment showed that there was a downward trend in Grade 3-4 neutropenia over time. Among those who experienced Grade 3-4 neutropenia, 71.7 % had no overlapping infections of any grade and none had overlapping Grade 3-4 infections. CONCLUSION: The magnitude of clinical benefit seen with the addition of palbociclib to letrozole in improving both median PFS and CBR rate is consistent in nearly all subgroups analyzed, and consistent with that seen in the overall study population. The safety profile of the combination treatment in all subgroups was also comparable to that in the overall safety population of the study.

The cyclin-dependent kinase 4/6 inhibitor palbociclib in combination with letrozole versus letrozole alone as first-line treatment of oestrogen receptor-positive, HER2-negative, advanced breast cancer (PALOMA-1/TRIO-18): a randomised phase 2 study.

BACKGROUND: Palbociclib (PD-0332991) is an oral, small-molecule inhibitor of cyclin-dependent kinases (CDKs) 4 and 6 with preclinical evidence of growth-inhibitory activity in oestrogen receptor-positive breast cancer cells and synergy with anti-oestrogens. We aimed to assess the safety and efficacy of palbociclib in combination with letrozole as first-line treatment of patients with advanced, oestrogen receptor-positive, HER2-negative breast cancer. METHODS: In this open-label, randomised phase 2 study, postmenopausal women with advanced oestrogen receptor-positive and HER2-negative breast cancer who had not received any systemic treatment for their advanced disease were eligible to participate. Patients were enrolled in two separate cohorts that accrued sequentially: in cohort 1, patients were enrolled on the basis of their oestrogen receptor-positive and HER2-negative biomarker status alone, whereas in cohort 2 they were also required to have cancers with amplification of cyclin D1 (CCND1), loss of p16 (INK4A or CDKN2A), or both. In both cohorts, patients were randomly assigned 1:1 via an interactive web-based randomisation system, stratified by disease site and disease-free interval, to receive continuous oral letrozole 2.5 mg daily or continuous oral letrozole 2.5 mg daily plus oral palbociclib 125 mg, given once daily for 3 weeks followed by 1 week off over 28-day cycles. The primary endpoint was investigator-assessed progression-free survival in the intention-to-treat population. Accrual to cohort 2 was stopped after an unplanned interim analysis of cohort 1 and the statistical analysis plan for the primary endpoint was amended to a combined analysis of cohorts 1 and 2 (instead of cohort 2 alone). The study is ongoing but closed to accrual; these are the results of the final analysis of progression-free survival. The study is registered with the ClinicalTrials.gov, number NCT00721409. FINDINGS: Between Dec 22, 2009, and May 12, 2012, we randomly assigned 165 patients, 84 to palbociclib plus letrozole and 81 to letrozole alone. At the time of the final analysis for progression-free survival (median follow-up 29.6 months [95% CI 27.9-36.0] for the palbociclib plus letrozole group and 27.9 months [25.5-31.1] for the letrozole group), 41 progression-free survival events had occurred in the palbociclib plus letrozole group and 59 in the letrozole group. Median progression-free survival was 10.2 months (95% CI 5.7-12.6) for the letrozole group and 20.2 months (13.8-27.5) for the palbociclib plus letrozole group (HR 0.488, 95% CI 0.319-0.748; one-sided p=0.0004). In cohort 1 (n=66), median progression-free survival was 5.7 months (2.6-10.5) for the letrozole group and 26.1 months (11.2-not estimable) for the palbociclib plus letrozole group (HR 0.299, 0.156-0.572; one-sided p<0.0001); in cohort 2 (n=99), median progression-free survival was 11.1 months (7.1-16.4) for the letrozole group and 18.1 months (13.1-27.5) for the palbociclib plus letrozole group (HR 0.508, 0.303-0.853; one-sided p=0.0046). Grade 3-4 neutropenia was reported in 45 (54%) of 83 patients in the palbociclib plus letrozole group versus one (1%) of 77 patients in the letrozole group, leucopenia in 16 (19%) versus none, and fatigue in four (4%) versus one (1%). Serious adverse events that occurred in more than one patient in the palbociclib plus letrozole group were pulmonary embolism (three [4%] patients), back pain (two [2%]), and diarrhoea (two [2%]). No cases of febrile neutropenia or neutropenia-related infections were reported during the study. 11 (13%) patients in the palbociclib plus letrozole group and two (2%) in the letrozole group discontinued the study because of adverse events. INTERPRETATION: The addition of palbociclib to letrozole in this phase 2 study significantly improved progression-free survival in women with advanced oestrogen receptor-positive and HER2-negative breast cancer. A phase 3 trial is currently underway. FUNDING: Pfizer.

Overall Survival and Updated Results for Sunitinib Compared With Interferon Alfa in Patients With Metastatic Renal Cell Carcinoma.

PURPOSE: A randomized, phase III trial demonstrated superiority of sunitinib over interferon alfa (IFN-α) in progression-free survival (primary end point) as first-line treatment for metastatic renal cell carcinoma (RCC). Final survival analyses and updated results are reported. PATIENTS AND METHODS: Seven hundred fifty treatment-naïve patients with metastatic clear cell RCC were randomly assigned to sunitinib 50 mg orally once daily on a 4 weeks on, 2 weeks off dosing schedule or to IFN-α 9 MU subcutaneously thrice weekly. Overall survival was compared by two-sided log-rank and Wilcoxon tests. Progression-free survival, response, and safety end points were assessed with updated follow-up. RESULTS: Median overall survival was greater in the sunitinib group than in the IFN-α group (26.4 v 21.8 months, respectively; hazard ratio [HR] = 0.821; 95% CI, 0.673 to 1.001; P = .051) per the primary analysis of unstratified log-rank test (P = .013 per unstratified Wilcoxon test). By stratified log-rank test, the HR was 0.818 (95% CI, 0.669 to 0.999; P = .049). Within the IFN-α group, 33% of patients received sunitinib, and 32% received other vascular endothelial growth factor-signaling inhibitors after discontinuation from the trial. Median progression-free survival was 11 months for sunitinib compared with 5 months for IFN-α (P < .001). Objective response rate was 47% for sunitinib compared with 12% for IFN-α (P < .001). The most commonly reported sunitinib-related grade 3 adverse events included hypertension (12%), fatigue (11%), diarrhea (9%), and hand-foot syndrome (9%). CONCLUSION: Sunitinib demonstrates longer overall survival compared with IFN-α plus improvement in response and progression-free survival in the first-line treatment of patients with metastatic RCC. The overall survival highlights an improved prognosis in patients with RCC in the era of targeted therapy.

Sunitinib versus interferon alfa in metastatic renal-cell carcinoma.

BACKGROUND: Since sunitinib malate has shown activity in two uncontrolled studies in patients with metastatic renal-cell carcinoma, a comparison of the drug with interferon alfa in a phase 3 trial is warranted. METHODS: We enrolled 750 patients with previously untreated, metastatic renal-cell carcinoma in a multicenter, randomized, phase 3 trial to receive either repeated 6-week cycles of sunitinib (at a dose of 50 mg given orally once daily for 4 weeks, followed by 2 weeks without treatment) or interferon alfa (at a dose of 9 MU given subcutaneously three times weekly). The primary end point was progression-free survival. Secondary end points included the objective response rate, overall survival, patient-reported outcomes, and safety. RESULTS: The median progression-free survival was significantly longer in the sunitinib group (11 months) than in the interferon alfa group (5 months), corresponding to a hazard ratio of 0.42 (95% confidence interval, 0.32 to 0.54; P<0.001). Sunitinib was also associated with a higher objective response rate than was interferon alfa (31% vs. 6%, P<0.001). The proportion of patients with grade 3 or 4 treatment-related fatigue was significantly higher in the group treated with interferon alfa, whereas diarrhea was more frequent in the sunitinib group (P<0.05). Patients in the sunitinib group reported a significantly better quality of life than did patients in the interferon alfa group (P<0.001). CONCLUSIONS: Progression-free survival was longer and response rates were higher in patients with metastatic renal-cell cancer who received sunitinib than in those receiving interferon alfa (ClinicalTrials.gov numbers, NCT00098657 and NCT00083889 [ClinicalTrials.gov]).

Using the Rasch model to validate and enhance the interpretation of the Functional Assessment of Cancer Therapy-Kidney Symptom Index--Disease-Related Symptoms scale.

OBJECTIVES: The Functional Assessment of Cancer Therapy-Kidney Symptom Index-Disease-Related Symptoms (FKSI-DRS) was developed to assess patients' kidney-cancer-related symptoms. The Rasch rating scale, a one-parameter logistic item response model, may enhance FKSI-DRS interpretation and validate its measurement properties. METHODS: We applied the Rasch model to FKSI-DRS data from a randomized phase 3 trial in which first-line sunitinib therapy showed superiority to interferon-alfa in patients with metastatic renal cell carcinoma. Of 750 enrolled patients, 668 patients completed the questionnaire on cycle 1, day 28 and were evaluated in the current study. The nine FKSI-DRS items were analyzed to enhance interpretation of the summary score by using an item characteristic curve that related score to probability of reporting specific symptoms. RESULTS: The Rasch model fitted the FKSI-DRS well: 8 of 9 items had acceptable infit and outfit statistics (<1.5, >0.5); item difficulty spanned a wide range (-3.23 to 1.64 logits); and the five response categories performed adequately. The item characteristic curve offered enhanced interpretation of FKSI-DRS: For example, an FKSI-DRS score of 27 (mean baseline score for total sample) indicated a 47% chance of reporting "no" to "lack of energy," although a two-point difference between sunitinib and interferon-alfa, averaged across all assessments (29 vs. 27), corresponded to sunitinib achieving a 28% increase (13% absolute difference) in the probability of reporting "no" to "lack of energy" (60% vs. 47%). CONCLUSIONS: Data suggest that the FKSI-DRS is an adequate measure of symptom status in patients with metastatic renal cell carcinoma. The Rasch model supports its validation and enhances its interpretation.

Patients with metastatic renal cell carcinoma with long-term disease-free survival after treatment with sunitinib and resection of residual metastases.

A complete response (CR) to therapy in patients with metastatic renal cell carcinoma (RCC) is rare but has been achieved in a minority of patients using high-dose interleukin-2. Surgical CR after partial response to immunotherapy in metastatic RCC has been anecdotally reported, although the low overall response rate to cytokines precludes this procedure in the majority of patients. Sunitinib is an oral, multitargeted receptor tyrosine kinase inhibitor with antiangiogenic and antitumor activity. Clinical efficacy has been demonstrated, with high objective response rates observed in a variety of solid tumor types, including RCC. Herein, we report 2 cases of patients with cytokine-refractory metastatic RCC who received sunitinib and achieved sufficient decrease in tumor burden to permit subsequent surgical resection, resulting in long-term CR.

Sunitinib in patients with metastatic renal cell carcinoma.

CONTEXT: Current treatment options for metastatic renal cell carcinoma (RCC) are limited and there is a need to identify novel and effective therapies. Sunitinib malate is an oral multitargeted tyrosine kinase inhibitor, which has shown activity in an initial study of cytokine-refractory metastatic RCC patients. OBJECTIVE: To confirm the antitumor efficacy of sunitinib as second-line treatment in patients with metastatic clear-cell RCC, the predominant cell type of this malignancy. DESIGN, SETTING, AND PATIENTS: Open-label, single-arm, multicenter clinical trial. Patients were enrolled between February and November 2004, with follow-up continuing until disease progression, unacceptable toxicity, or withdrawal of consent. The reported data apply through August 2005. Patients (N = 106) had metastatic clear-cell RCC, which had progressed despite previous cytokine therapy. INTERVENTION: Repeated 6-week cycles of sunitinib, 50 mg per day given orally for 4 consecutive weeks followed by 2 weeks off per treatment cycle. MAIN OUTCOME MEASURES: Assessment of clinical response, degree of tumor regression on imaging studies using the Response Evaluation Criteria in Solid Tumors (RECIST) guidelines. Primary end point was overall objective response rate (complete plus partial). Secondary end points were progression-free survival and safety. Response was evaluated by independent third-party core imaging laboratory and by treating physicians (investigator assessment). RESULTS: All 106 patients received sunitinib and were included in the intent-to-treat population for safety analyses. Of these, 105 patients were evaluable for efficacy analyses. The objective response rate according to an independent third-party assessment resulted in 36 patients with partial response (34%; 95% confidence interval, 25%-44%), and a median progression-free survival of 8.3 months (95% confidence interval, 7.8-14.5 months). The most common adverse events experienced by patients were fatigue in 30 (28%) and diarrhea 21 (20%). Neutropenia, elevation of lipase, and anemia were the most common laboratory abnormalities observed in 45 (42%), 30 (28%), and 27 (26%) patients, respectively. CONCLUSION: The results of this trial demonstrate the efficacy and manageable adverse-event profile of sunitinib as a single agent in second-line therapy for patients with cytokine-refractory metastatic clear-cell RCC. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00077974.

Phase 1/2 study of cyclin-dependent kinase (CDK)4/6 inhibitor palbociclib (PD-0332991) with bortezomib and dexamethasone in relapsed/refractory multiple myeloma.

This phase 1/2 study was the first to evaluate the safety and efficacy of the cyclin-dependent kinase (CDK) 4/6-specific inhibitor palbociclib (PD-0332991) in sequential combination with bortezomib and dexamethasone in relapsed/refractory multiple myeloma. The recommended phase 2 dose was palbociclib 100 mg orally once daily on days 1-12 of a 21-day cycle with bortezomib 1.0 mg/m2 (intravenous) and dexamethasone 20 mg (orally 30 min pre-bortezomib dosing) on days 8 and 11 (early G1 arrest) and days 15 and 18 (cell cycle resumed). Dose-limiting toxicities were primarily cytopenias; most other treatment-related adverse events were grade≤3. At a bortezomib dose lower than that in other combination therapy studies, antitumor activity was observed (phase 1). In phase 2, objective responses were achieved in 5 (20%) patients; 11 (44%) achieved stable disease. Biomarker and pharmacodynamic assessments demonstrated that palbociclib inhibited CDK4/6 and the cell cycle initially in most patients.

Circulating proteins as potential biomarkers of sunitinib and interferon-α efficacy in treatment-naïve patients with metastatic renal cell carcinoma.

PURPOSE: We investigated potential biomarkers of efficacy in a phase III trial of sunitinib versus interferon-alpha (IFN-α), first-line in metastatic renal cell carcinoma (mRCC), by analyzing plasma levels of vascular endothelial growth factor (VEGF)-A, VEGF-C, soluble VEGF receptor-3 (sVEGFR-3) and interleukin (IL)-8. METHODS: Seven hundred and fifty mRCC patients were randomized to oral sunitinib 50 mg/day in repeated cycles of a 4-week on/2-week off schedule or IFN-α 9 million units subcutaneously thrice weekly. Plasma samples collected from a subset of 63 patients on days 1 and 28 of cycles 1-4 and at end of treatment were analyzed by ELISA. RESULTS: Baseline characteristics of biomarker-evaluated patients in sunitinib (N = 33) and IFN-α (N = 30) arms were comparable to their respective intent-to-treat populations. By univariate Cox regression analysis, low baseline soluble protein levels were associated with lower risk of progression/death (all P < 0.05): in both treatment arms, baseline VEGF-A and IL-8 were associated with overall survival (OS) and baseline VEGF-C with progression-free survival (PFS); in the sunitinib arm, baseline VEGF-A was associated with PFS and baseline sVEGFR-3 with PFS and OS; in the IFN-α arm, baseline IL-8 was associated with PFS. In multivariate analysis, baseline sVEGFR-3 and IL-8 remained independent predictors of OS in the sunitinib arm, while no independent predictors of outcome remained in the IFN-α arm. Pharmacodynamic changes were not associated with PFS or OS for any plasma protein investigated. CONCLUSIONS: Our findings suggest that, in mRCC, baseline VEGF-A and IL-8 may have prognostic value, while baseline sVEGFR-3 may predict sunitinib efficacy.

Analyzing the pivotal trial that compared sunitinib and IFN-α in renal cell carcinoma, using a method that assesses tumor regression and growth.

PURPOSE: We applied a method that analyzes tumor response, quantifying the rates of tumor growth (g) and regression (d), using tumor measurements obtained while patients receive therapy. We used data from the phase III trial comparing sunitinib and IFN-α in metastatic renal cell carcinoma (mRCC) patients. METHODS: The analysis used an equation that extracts d and g. RESULTS: For sunitinib, overall survival (OS) was strongly correlated with log g (Rsq = 0.44, P < 0.0001); much less with log d (Rsq = 0.04; P = 0.0002). The median g of tumors in these patients (0.00082 per days; log g = -3.09) was about half that (P < 0.001) of tumors in patients receiving IFN-α (0.0015 per day; log g = -2.81). With IFN-α, the OS/log g correlation (Rsq = 0.14) was weaker. Values of g from measurements obtained by study investigators or central review were highly correlated (Rsq = 0.80). No advantage resulted in including data from central review in regressions. Furthermore, g can be estimated accurately four months before treatment discontinuation. Extrapolating g in a model that incorporates survival generates the hypothesis that g increased after discontinuation of sunitinib but did not accelerate. CONCLUSIONS: In patients with mRCC, sunitinib reduced tumor growth rate, g, more than did IFN-α. Correlating g with OS confirms earlier analyses suggesting g may be an important clinical trial endpoint, to be explored prospectively and in individual patients.

Sunitinib in combination with paclitaxel plus carboplatin in patients with advanced solid tumors: phase I study results.

PURPOSE: To evaluate the maximum tolerated dose (MTD), safety, and antitumor activity of sunitinib combined with paclitaxel and carboplatin. METHODS: Successive cohorts of patients with advanced solid tumors received oral sunitinib (25, 37.5, or 50 mg) for 2 consecutive weeks of a 3-week cycle (Schedule 2/1) or as a continuous daily dose for 3-week cycles (CDD schedule) in combination with paclitaxel (175-200 mg/m(2)) plus carboplatin (AUC 6 mg min/ml) on day one of each of 4 cycles. Dose-limiting toxicities (DLTs) and adverse events (AEs) were evaluated to determine the MTD. Efficacy parameters were analyzed in patients with measurable disease. RESULTS: Forty-three patients were enrolled (n = 25 Schedule 2/1; n = 18 CDD schedule). Across all doses, 6 DLTs were observed [grade 4 papilledema, grade 5 GI hemorrhage, grade 3 neutropenic infection, and grade 4 thrombocytopenia (n = 3)]. The MTD for Schedule 2/1 was sunitinib 25 mg plus paclitaxel 175 mg/m(2) and carboplatin AUC 6 mg min/ml. The MTD was not determined for the CDD schedule. Treatment-related AEs included neutropenia (77%), thrombocytopenia (56%), and fatigue (47%). Of 38 evaluable patients, 4 (11%) had partial responses and 12 (32%) had stable disease. PK data indicated an increase in maximum and total plasma exposures to sunitinib and its active metabolite when given with paclitaxel and carboplatin compared with sunitinib monotherapy. CONCLUSIONS: Myelosuppression resulting in prolonged dose delays and frequent interruptions was observed, suggesting that this treatment combination is not feasible in the general cancer population.

Phase II study of sunitinib as maintenance therapy in patients with locally advanced or metastatic non-small cell lung cancer.

This open-label, phase II study evaluated the antitumor activity and safety of sunitinib monotherapy as maintenance treatment following first-line chemotherapy in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC). Following treatment with standard doublet chemotherapy (paclitaxel and carboplatin), patients received oral sunitinib (starting dose 50mg/day) in 6-week cycles (Schedule 4/2: 4 weeks on treatment, 2 weeks off treatment) until disease progression, unacceptable toxicity or withdrawal of consent. The primary endpoint was probability of survival at 1 year ≥55%. Of 84 patients who received first-line chemotherapy, 66 (79%) received sunitinib maintenance therapy (median sunitinib cycles started: 2 [range 1-20]). Probability of survival at 1 year was 40.5% (95% confidence interval [CI]: 29.8, 51.0). Median overall survival was 10.4 months (95% CI: 8.0, 12.2). The objective response rate was 27.4% (95% CI: 18.2, 38.2). The most frequently reported all-causality adverse events of any grade during sunitinib maintenance therapy were fatigue/asthenia (55%), diarrhea (36%), and nausea (32%). These data suggest that maintenance therapy may have value in NSCLC, although the primary endpoint of the study was not met.

Phase I/II trial of sunitinib plus gefitinib in patients with metastatic renal cell carcinoma.

OBJECTIVES: Sunitinib is an oral, multitargeted tyrosine kinase inhibitor of vascular endothelial growth factor and platelet-derived growth factor receptors with proven clinical benefit in patients with metastatic renal cell carcinoma (RCC). This phase I/II study investigated sunitinib in combination with an epidermal growth factor receptor inhibitor, gefitinib, in patients with metastatic RCC. METHODS: In phase I, patients received sunitinib 37.5 or 50 mg in 6-week cycles (4 weeks on treatment, 2 off) plus gefitinib 250 mg, both once daily, to determine the sunitinib maximum tolerated dose (MTD). Pharmacokinetics was assessed for both drugs. In phase II, patients received sunitinib MTD plus gefitinib to evaluate the safety and antitumor activity of this combination. RESULTS: Forty-two patients were enrolled: 11 in phase I, and 31 in phase II. In phase I, 2 dose-limiting toxicities were observed with sunitinib 50 mg (grade 2 left ventricular ejection fraction decline and grade 3 fatigue), and 37.5 mg was declared the MTD. Thirteen patients treated at the MTD achieved a partial response (objective response rate: 37%; 95% confidence interval, 22-55) and 12 (34%) had stable disease. Median progression-free survival was 11 months (95% confidence interval, 6-17). The most commonly reported grade 3/4 treatment-related adverse event was diarrhea (14%), the only grade 3/4 adverse event to occur in >2 patients. Pharmacokinetic analyses did not indicate any drug-drug interactions. CONCLUSIONS: In metastatic RCC, sunitinib plus gefitinib demonstrated comparable efficacy to sunitinib monotherapy with an acceptable safety profile. Dosing, pharmacokinetic profile, and safety support study of sunitinib plus an epidermal growth factor receptor inhibitor in other tumor types.

Quality of life predicts progression-free survival in patients with metastatic renal cell carcinoma treated with sunitinib versus interferon alfa.

In a randomized phase III trial, sunitinib was associated with significantly superior progression-free survival when compared with interferon alfa as first-line therapy in patients with metastatic renal cell carcinoma. This article investigates whether baseline quality of life and demographic and clinical variables were predictive for progression-free survival.

Overall survival and updated results for sunitinib compared with interferon alfa in patients with metastatic renal cell carcinoma.

PURPOSE: A randomized, phase III trial demonstrated superiority of sunitinib over interferon alfa (IFN-alpha) in progression-free survival (primary end point) as first-line treatment for metastatic renal cell carcinoma (RCC). Final survival analyses and updated results are reported. PATIENTS AND METHODS: Seven hundred fifty treatment-naïve patients with metastatic clear cell RCC were randomly assigned to sunitinib 50 mg orally once daily on a 4 weeks on, 2 weeks off dosing schedule or to IFN-alpha 9 MU subcutaneously thrice weekly. Overall survival was compared by two-sided log-rank and Wilcoxon tests. Progression-free survival, response, and safety end points were assessed with updated follow-up. RESULTS: Median overall survival was greater in the sunitinib group than in the IFN-alpha group (26.4 v 21.8 months, respectively; hazard ratio [HR] = 0.821; 95% CI, 0.673 to 1.001; P = .051) per the primary analysis of unstratified log-rank test (P = .013 per unstratified Wilcoxon test). By stratified log-rank test, the HR was 0.818 (95% CI, 0.669 to 0.999; P = .049). Within the IFN-alpha group, 33% of patients received sunitinib, and 32% received other vascular endothelial growth factor-signaling inhibitors after discontinuation from the trial. Median progression-free survival was 11 months for sunitinib compared with 5 months for IFN-alpha (P < .001). Objective response rate was 47% for sunitinib compared with 12% for IFN-alpha (P < .001). The most commonly reported sunitinib-related grade 3 adverse events included hypertension (12%), fatigue (11%), diarrhea (9%), and hand-foot syndrome (9%). CONCLUSION: Sunitinib demonstrates longer overall survival compared with IFN-alpha plus improvement in response and progression-free survival in the first-line treatment of patients with metastatic RCC. The overall survival highlights an improved prognosis in patients with RCC in the era of targeted therapy.

Economic evaluation of sunitinib malate for the first-line treatment of metastatic renal cell carcinoma.

PURPOSE: To assess the cost effectiveness and cost utility of sunitinib malate as a first-line treatment in metastatic renal cell carcinoma (mRCC) compared with interferon-alfa (IFN-alpha) and interleukin-2 (IL-2) from a US societal perspective. METHODS: A Markov model was developed to simulate disease progression and to determine progression-free survival, total life-years (LYs), and quality-adjusted life-years (QALYs) gained. Model parameters were derived from the pivotal trial of sunitinib, published literature, government sources, and clinical experts' opinions. The model included trial-based adverse events (AEs). Costs of drug treatment, routine follow-up, AEs, disease progression, and best supportive care (BSC) of terminally ill patients were included. Results were tested using probabilistic and deterministic sensitivity analyses. RESULTS: Treatment with sunitinib is associated with a gain in progression-free years of 0.41 and 0.35 over IFN-alpha and IL-2. The estimated gains over IFN-alpha were 0.11 LYs and 0.14 QALYs, and over IL-2 were 0.24 LYs and 0.20 QALYs. Both IFN-alpha and sunitinib treatments dominate IL-2 treatment; the incremental cost-effectiveness ratio of sunitinib versus IFN-alpha was $18,611 per progression-free year gained and $67,215 per LY gained, and the cost-utility ratio is $52,593 per QALY gained (at a 5% discount rate). Sensitivity analyses found the results to be most sensitive to utility values during treatment, the cost of sunitinib, and the cost of BSC. Model results were robust to changes in other model variables. CONCLUSION: These results suggest that sunitinib is a cost-effective alternative to IFN-alpha as a first-line treatment for mRCC.

Quality of life in patients with metastatic renal cell carcinoma treated with sunitinib or interferon alfa: results from a phase III randomized trial.

PURPOSE: In an international, randomized phase III trial, sunitinib demonstrated statistically significant efficacy over interferon alfa (IFN-alpha) as first-line therapy in patients with metastatic renal cell carcinoma (mRCC) (progression-free survival time, 11 v 5 months, respectively; P < .001; objective response rate, 31% v 6%, respectively; P < .001). We report health-related quality-of-life (QOL) results from this trial. PATIENTS AND METHODS: Seven hundred fifty mRCC patients were randomly assigned to sunitinib (6-week cycles: 50 mg orally once daily for 4 weeks, followed by 2 weeks off) or IFN-alpha (9 million units subcutaneous injections, three times weekly). QOL measures included the Functional Assessment of Cancer Therapy-General (FACT-G), the FACT-Kidney Symptom Index-15 item (FKSI-15), and the EuroQoL-5D's utility score (EQ-5D Index) and its visual analog scale (EQ-VAS). The primary QOL end point was the FKSI Disease-Related Symptoms (FKSI-DRS) subscale. Higher scores indicated better outcomes (better QOL or fewer symptoms). Data were analyzed for the intent-to-treat population using mixed-effects models, supplemented with pattern-mixture models. RESULTS: Patients receiving sunitinib reported higher FKSI-15 and FKSI-DRS scores at each cycle than those receiving IFN-alpha, with a significant difference in the overall least squares means (3.27 and 1.98, respectively; P < .0001). Similarly, differences in least squares means for FACT-G (and all subscales), EQ-5D Index, and EQ-VAS were all significantly favorable for sunitinib (P < .01). Per pre-established thresholds, between-treatment differences in the mean scores were clinically meaningful after cycle 4 for FKSI-DRS and at all assessments for FKSI-15, FACT-G, and the FACT-G functional well-being subscale. CONCLUSION: Sunitinib provides superior QOL compared with IFN-alpha in mRCC patients.

Prognostic nomogram for sunitinib in patients with metastatic renal cell carcinoma.

BACKGROUND: In a randomized, phase 3 trial, sunitinib demonstrated superior efficacy over interferon-alfa as first-line therapy in patients with metastatic clear-cell renal cell carcinoma (RCC). On the basis of outcome data from that trial, the authors developed a nomogram for predicting the probability of 12-month progression-free survival for patients who received sunitinib therapy. METHODS: Three-hundred seventy-five patients who received sunitinib in the phase 3 trial were the subject of the current analysis. Nomogram pretreatment predictor variables included corrected serum calcium levels, the number of metastatic sites, hemoglobin levels, prior nephrectomy, the presence of lung and liver metastases, thrombocytosis, Eastern Cooperative Oncology Group performance status, time from diagnosis to treatment, and serum levels of alkaline phosphatase and lactate dehydrogenase. Investigator-assessed progression-free survival was the predicted outcome endpoint. Internal validation of the nomogram consisted of quantification of the discrimination with the concordance index and assessment of calibration. RESULTS: One-hundred seventy-four of 375 patients (46%) who received sunitinib achieved an objective response, and the median progression-free survival was 10.8 months (95% confidence interval, 10.6-12.6 months). A nomogram for predicting the probability of 12-month progression-free survival for patients who received sunitinib therapy was constructed on the basis of a Cox regression model from 11 parameters that were determined before treatment. The concordance index was 0.633. CONCLUSIONS: A nomogram was developed from pretreatment clinical features to predict the probability of achieving 12-month progression-free survival with sunitinib therapy for metastatic clear-cell RCC. The authors concluded that independent validation of the nomogram and additional studies to identify tumor-specific prognostic factors are warranted.

Antitumor activity and biomarker analysis of sunitinib in patients with bevacizumab-refractory metastatic renal cell carcinoma.

PURPOSE: To assess the safety and efficacy of sunitinib in patients with bevacizumab-refractory metastatic renal cell carcinoma (mRCC) and explore biomarkers for sunitinib response. PATIENTS AND METHODS: Patients with mRCC and disease progression after bevacizumab-based therapy received oral sunitinib 50 mg once daily in 6-week cycles on a 4/2 schedule (4 weeks with treatment followed by 2 weeks without treatment) in a phase II multicenter study. The primary end point was objective response rate (ORR). Secondary end points included progression-free survival (PFS), duration of response (DR), overall survival (OS), and safety. Plasma soluble proteins (vascular endothelial growth factor [VEGF]-A, VEGF-C, soluble VEGF receptor [sVEGFR]-3, and placental growth factor [PlGF]) levels were measured. RESULTS: Sixty-one patients were enrolled. The ORR was 23.0% (95% CI, 13.2% to 35.5%), median PFS was 30.4 weeks (95% CI, 18.3 to 36.7 weeks), median DR was 44.1 weeks (95% CI, 25.0 to 102.7 weeks), and median OS was 47.1 weeks (95% CI, 36.9 to 79.4 weeks). Mean plasma VEGF-A and PlGF levels significantly increased whereas VEGF-C and sVEGFR-3 levels decreased with sunitinib treatment. Lower baseline levels of sVEGFR-3 and VEGF-C were associated with longer PFS and ORR. Most treatment-related adverse events were of mild-to-moderate intensity and included fatigue, hypertension, and hand-foot syndrome. CONCLUSION: Sunitinib has substantial antitumor activity in patients with bevacizumab-refractory mRCC and modulates circulating VEGF pathway biomarkers. These data support the hypothesis that sunitinib inhibits signaling pathways involved in bevacizumab resistance. Baseline levels of sVEGFR-3 and VEGF-C may have potential utility as biomarkers of clinical efficacy in this setting.

Activity of SU11248, a multitargeted inhibitor of vascular endothelial growth factor receptor and platelet-derived growth factor receptor, in patients with metastatic renal cell carcinoma.

PURPOSE: Renal cell carcinoma (RCC) is characterized by loss of von Hippel Lindau tumor suppressor gene activity, resulting in high expression of pro-angiogenic growth factors: vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF). SU11248 (sunitinib malate), a small molecule inhibitor with high binding affinity for VEGF and PDGF receptors, was tested for clinical activity in patients with metastatic RCC. PATIENTS AND METHODS: Patients with metastatic RCC and progression on first-line cytokine therapy were enrolled onto a multicenter phase II trial. SU11248 monotherapy was administered in repeated 6-week cycles of daily oral therapy for 4 weeks, followed by 2 weeks off. Overall response rate was the primary end point, and time to progression and safety were secondary end points. Results Twenty-five (40%) of 63 patients treated with SU11248 achieved partial responses; 17 additional patients (27%) demonstrated stable disease lasting > or = 3 months. Median time to progression in the 63 patients was 8.7 months. Dosing was generally tolerated with manageable toxicities. CONCLUSION: SU11248, a multitargeted receptor tyrosine kinase inhibitor of VEGF and PDGF receptors, demonstrates antitumor activity in metastatic RCC as second-line therapy, a setting where no effective systemic therapy is presently recognized. The genetics of RCC and these promising clinical results support the hypothesis that VEGF and PDGF receptor-mediated signaling is an effective therapeutic target in RCC.