The phase III COMPARZ study showed noninferior efficacy of pazopanib versus sunitinib in advanced renal cell carcinoma. In this COMPARZ post hoc analysis we characterized pazopanib responders, patient subgroups with better outcomes, and the effect of dose modification on efficacy and safety.
Patients were randomized to pazopanib 800 mg/d (n = 557) or sunitinib 50 mg/d, 4 weeks on/2 weeks off (n = 553). Secondary end points included time to complete response (CR)/partial response (PR); the proportion of patients with CR/PR ≥10 months and progression-free survival (PFS) ≥10 months; efficacy in patients with baseline metastasis; and logistic regression analyses of patient characteristics associated with CR/PR ≥10 months. Median PFS, objective response rate (ORR), and safety were evaluated in patients with or without dose reductions or interruptions lasting ≥7 days.
Median time to response was numerically shorter for patients treated with pazopanib versus sunitinib (11.9 vs. 17.4 weeks). Similar percentages of pazopanib and sunitinib patients had CR/PR ≥10 months (14% and 13%, respectively), and PFS ≥10 months (31% and 34%, respectively). For patients without versus with adverse event (AE)-related dose reductions, median PFS, median overall survival, and ORR were 7.3 versus 12.5 months, 21.7 versus 36.8 months, and 22% versus 42% (all P < .0001) for pazopanib, and 5.5 versus 13.8 months, 18.1 versus 38.0 months, and 16% versus 34% (all P < .0001) for sunitinib; results were similar for dose interruptions.
Dose modifications when required because of AEs were associated with improved efficacy, suggesting that AEs might be used as a surrogate marker of adequate dosing for individual patients.
Clinical genitourinary cancer. 2019 Feb 06 [Epub]
Cora N Sternberg, Robert J Motzer, Thomas E Hutson, Toni K Choueiri, Christian Kollmannsberger, Georg A Bjarnason, Camillo Porta, Viktor Grünwald, Luca Dezzani, Jackie Han, Nizar M Tannir
Weill Cornell Medicine, Hematology/Oncology, New York, NY. Electronic address: ., Memorial Sloan Kettering Cancer Center, New York, NY., Texas Oncology/Baylor Sammons Cancer Center, Dallas, TX., Department of Medical Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA., Division of Medical Oncology, The University of British Columbia, BCCA Vancouver Cancer Centre, Vancouver, British Columbia, Canada., Division of Medical Oncology, Sunnybrook Odette Cancer Centre, University of Toronto, Toronto, Ontario, Canada., Medical Oncology, I.R.C.C.S. San Matteo University Hospital Foundation, Pavia, Italy., University Hospital Essen, West-German Cancer Center, Internal Medicine (Tumor research) and Clinic for Urology, Essen, Germany., Novartis Pharmaceuticals Corporation, East Hanover, NJ., Department of Genitourinary Medical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX.