810P - Tolerability of Targeted Agents in First-Line Treatment of Metastatic Renal Cell Carcinoma (MRCC)

Abstract

ABSTRACT Objectives Between 2005 and 2009, six targeted agents were approved for the treatment of mRCC in the US. Clinical trials have reported median progression-free survival (PFS) of up to 11 months for treatment-naive patients. None has demonstrated an improvement in median overall survival versus another targeted agent. This study aims to determine the tolerability of these agents in real-world practices. Methods Adult patients with mRCC diagnosed between Jan 1, 2006 and Dec 31, 2010 were identified from a large commercial insurance claims and Medicare supplemental database in the US. A minimum follow-up of 3 months and ≥1 pharmacy or medical claims on or after metastasis diagnosis date were required for one of the targeted agents: sunitinib (SUN), sorafenib (SOR), pazopanib (PAZ), everolimus (EVE), temsirolimus (TEM), or bevacizumab with or without interferon alpha (BEV). Tolerability was measured by rate of dose reduction and duration of treatment. Median duration of treatment was assessed using the Kaplan-Meier method. Adverse events (AE) were based on diagnosis or treatment indicative of AEs commonly associated with these agents. Results 1,622 patients were identified, of which 1,079 received first-line SUN, 284 SOR, 168 TEM, 40 PAZ, 26 EVE, and 25 BEV. With a median follow up of 13 months, median duration of treatment was the longest for PAZ (6.9 mos), followed by SOR and EVE (both 4.9 mos), SUN (4.8 mos), TEM (3.5 mos) and BEV (1.0 mo). Dose reduction was observed in a higher percentage of patients receiving SUN (26%) compared to TEM (18.5%), BEV (12.5%), EVE (7.7%), PAZ (7.5%), and SOR (6%). Claims of AEs were 93%, 86%, 86%, 85%, 80%, and 56% for TEM, SUN, SOR, EVE, PAZ, and BEV, respectively. Conclusions Rates of AEs appear to be high among commonly used first-line agents, including the recently approved PAZ and EVE, and there was substantial need for dose reduction for the most prescribed SUN. Duration of treatment appeared to be substantially shorter than published PFS values, assuming treatment until progression for the majority of patients. It is important to determine if AEs may have led to reduced dose and shortened duration of treatment and how costs of care and patient outcomes might be affected. Disclosure Y. Su: Employment and Leadership Role: Bristol-Myers Squibb (employment, myself, compensated). Stock Ownership: Bristol-Myers Squibb (myself). P. Landsman-Blumberg: Stock Ownership: Merck & Co., Inc. (myself). C. Poehlein: Employment and Leadership Role: Bristol-Myers Squibb (employment, myself, compensated). Stock Ownership: Bristol-Myers Squibb (myself). I. Waxman: Employment and Leadership Role: Bristol-Myers Squibb (employment, myself, compensated). Stock Ownership: Bristol-Myers Squibb (myself). All other authors have declared no conflicts of interest.