Factors Associated with Adherence Rates for Oral and Intravenous Anticancer Therapy in Commercially Insured Patients with Metastatic Colon Cancer.

BACKGROUND: Over the past decade, oncology therapies have trended toward orally administered regimens, and there has been growing attention on evaluation of factors that affect adherence. There has not been a rigorous investigation of factors associated with adherence to intravenous (i.v.) and oral anticancer drugs in the setting of metastatic colorectal cancer (mCRC). OBJECTIVES: To (a) assess potential patient-specific factors related to adherence to mCRC chemotherapy regimens and (b) compare adherence with IV versus oral dosage forms. METHODS: A retrospective analysis was performed using the Optum Oncology Management claims database. Patients aged 18 years and older diagnosed with mCRC between July 1, 2004, and December 31, 2010, who were insured by a commercial health plan were included in the study. Adherence to i.v. and oral chemotherapy regimens was assessed using the National Comprehensive Cancer Network (NCCN) guidelines as the standard for expected cycle/regimen duration. The most commonly prescribed chemotherapy regimens were assessed. Adherence was evaluated using the medication possession ratio (MPR), calculated as the number of days a patient was covered by their chemotherapy regimen, according to NCCN guidelines, divided by the number of days elapsed from the first to the last infusion of that regimen. For most analyses, the MPR was considered a continuous variable that could take on values between 0 and 1. In other analyses, a dichotomous categorical variable designated if the MPR was at least 0.8 versus less than 0.8. The Wilcoxon rank sum, Kruskal-Wallis, and Student's t-test were used to detect differences in continuous measures between patients receiving oral capecitabine therapy versus i.v. chemotherapy. The chi square test (X(2) test) or Fisher's exact test was used to assess differences in the dichotomous MPR variable. Generalized estimating equation (GEE) models were used for regimen-level analyses to account for correlated responses within individuals. RESULTS: A total of 6,780 patients were included in the analysis, virtually all (98%) with commercial insurance coverage and the remaining (2%) with Medicare Advantage. Patients with mCRC received 17,095 regimens of chemotherapy, including 2,252 regimens of oral capecitabine. Of the 17,095 regimens, 6,780 (40%) were first-line regimens (i.e., the first time mCRC was treated for a given patient). The most common chemotherapy regimen, regardless of line of therapy, was FOLFOX (2,991 regimens, 17.5% of all regimens used). FOLFOX-based therapies with or without bevacizumab were the most common regimens for first- and second-line chemotherapy, while oral capecitabine treatment was the most commonly prescribed regimen for patients in third- or fourth-line therapy. Overall, medication adherence across all regimens was relatively high, with a mean MPR of 0.87 (SD = 0.17). Evaluation of the distribution of i.v. and oral capecitabine regimens revealed that 28% of all regimens were associated with an MPR of less than 0.8. The average MPR was clinically similar, but statistically higher for i.v. chemotherapy regimens (0.881) compared with oral capecitabine regimens (0.799; P < 0.0001). In the multivariable GEE model, lung or liver metastases were associated with a higher MPR, while lower Charlson Comorbidity Index and oral anticancer therapy were associated with lower MPR. Furthermore, as line of therapy increased, the difference in MPR between patients receiving oral capecitabine and i.v. chemotherapy increased. CONCLUSIONS: This analysis determined that adherence with i.v. chemotherapy regimens was clinically similar, but statistically higher, compared to oral capecitabine therapy. The difference in adherence rates between the 2 routes of administration increased as the line of anticancer regimen increased. These results suggest that there should be an increased focus on improving adherence rates in patients receiving oral capecitabine.

Sorafenib for treatment of renal cell carcinoma: Final efficacy and safety results of the phase III treatment approaches in renal cancer global evaluation trial.

PURPOSE: Mature survival data and evaluation of vascular endothelial growth factor (VEGF) as a prognostic biomarker from the Treatment Approaches in Renal Cancer Global Evaluation Trial (TARGET) study in patients with renal cell carcinoma (RCC) are reported. PATIENTS AND METHODS: Nine hundred three previously treated patients were randomly assigned to receive sorafenib versus placebo. On demonstration of progression-free survival (PFS) benefit with sorafenib, patients assigned to placebo were offered sorafenib. Overall survival (OS) was determined at two planned interim analyses and one final analysis, with a secondary OS analysis conducted by censoring placebo patients who crossed over to sorafenib. The relationships between baseline VEGF level and prognosis and efficacy were evaluated. RESULTS: The final OS of patients receiving sorafenib was comparable with that of patients receiving placebo (17.8 v 15.2 months, respectively; hazard ratio [HR] = 0.88; P = .146); however, when post-cross-over placebo survival data were censored, the difference became significant (17.8 v 14.3 months, respectively; HR = 0.78; P = .029). Adverse events at 16 months after cross over were similar to those previously reported. Baseline VEGF levels correlated with Eastern Cooperative Oncology Group performance status (P < .0001), Memorial Sloan-Kettering Cancer Center score (P < .0001), and PFS and OS in univariate (PFS, P = .0013; OS, P = .0009) and multivariate (PFS, P = .0231; OS, P = .0416) analyses of placebo patients and with short OS by multivariate analysis of patients receiving sorafenib (P = .0145). Both high-VEGF (P < .01) and low-VEGF (P < .01) groups benefited from sorafenib. CONCLUSION: Although an OS benefit was not seen on a primary intent-to-treat analysis, results of a secondary OS analysis censoring placebo patients demonstrated a survival advantage for those receiving sorafenib, suggesting an important cross-over effect. VEGF levels are prognostic for PFS and OS in RCC. The results of TARGET establish the efficacy and safety of sorafenib in advanced RCC.

Sorafenib for older patients with renal cell carcinoma: subset analysis from a randomized trial.

BACKGROUND: The perception that older cancer patients may be at higher risk than younger patients of toxic effects from cancer therapy but may obtain less clinical benefit from it may be based on the underrepresentation of older patients in clinical trials and the known toxic effects of cytotoxic chemotherapy. It is not known how older patients respond to targeted therapy. METHODS: This retrospective subgroup analysis of data from the phase 3, randomized Treatment Approach in Renal Cancer Global Evaluation Trial examined the safety and efficacy of sorafenib in older (age >or=70 years, n = 115) and younger patients (age <70 years, n = 787) who received treatment for advanced renal cell carcinoma. Patient demographics and progression-free survival were recorded. Best tumor response, clinical benefit rate (defined as complete response plus partial response plus stable disease), time to self-reported health status deterioration, and toxic effects were assessed by descriptive statistics. Health-related quality of life was assessed with a Cox proportional hazards model. Kaplan-Meier analyses were used to summarize time-to-event data. RESULTS: Median progression-free survival was similar in sorafenib-treated younger patients (23.9 weeks; hazard ratio [HR] for progression compared with placebo = 0.55, 95% confidence interval [CI] = 0.47 to 0.66) and older patients (26.3 weeks; HR = 0.43, 95% CI = 0.26 to 0.69). Clinical benefit rates among younger and older sorafenib-treated patients were also similar (83.5% and 84.3%, respectively) and were superior to those of younger and older placebo-treated patients (53.8% and 62.2%, respectively). Adverse events were predictable and manageable regardless of age. Sorafenib treatment delayed the time to self-reported health status deterioration among both older patients (121 days with sorafenib vs 85 days with placebo; HR = 0.66, 95% CI = 0.43 to 1.03) and younger patients (90 days with sorafenib vs 52 days with placebo; HR = 0.69, 95% CI = 0.59 to 0.81) and improved quality of life over that time. CONCLUSIONS: Among patients with advanced renal cell carcinoma receiving sorafenib treatment, outcomes of older (>or=70 years) and younger (<70 years) patients were similar.