ESMO 2016. Abstract 819P. Real world outcomes of patients with metastatic renal cell carcinoma (mRCC) using first-line sunitinib or pazopanib: The Canadian experience
A. Lalani et al.
Results: Our cohort included 670 patients: 93 treated with pazopanib and 577 with sunitinib. Median TTF was greater in patients treated with sunitinib versus pazopanib (6.0 vs 3.7 mos, p = 0.046) and maintained significance when adjusted for IMDC criteria (hazard ratio [HR] 0.61, 0.41-0.90 95% CI, p = 0.013). Median OS was better in patients treated with sunitinb (31.9 vs 20.6 mos, p = 0.028) and maintained significance when adjusted for IMDC criteria (HR 0.60, 0.38-0.95 95% CI, p = 0.028). Common toxicities requiring dose modification, including fatigue and diarrhea, were similar between both groups. However, patients treated with sunitinib had a significantly higher incidence of mucositis, hand-foot syndrome, and GERD; patients treated with pazopanib had a significantly higher incidence of liver toxicity and a trend towards weight loss.
Conclusions: In Canadian patients with clear cell mRCC, survival and treatment duration appears to favour sunitinib over pazopanib. Plausible explanations include potential differences in patient selection for pazopanib, the contemporary experience with individualized dosing on sunitinib, and small sample size. These data on real world toxicities are informative and may aid physicians and patients in guiding treatment decisions.
CARE Faculty Perspective: The results of this study should be interpreted within the limitations of a real-world data set, including the retrospective data collection and potential selection bias. Real world outcomes for sunitinib and pazopanib compare favourably to the outcomes observed in phase III studies.
Overall survival in this Canadian patient population was superior for patients treated with sunitinib vs pazopanib, even when adjusted for IMDC prognostic factors. Whether this result is due to bias or patient selection or other factors such as the use of dose/schedule individualization for sunitinib should be further examined. The results of the Canadian prospective study on sunitinib dose/schedule individualization are eagerly awaited.
ESMO 2016. 738P. Meta-analysis of randomized clinical trials in metastatic castration resistant prostate cancer: Comparison of hypertension, neurological and psychiatric adverse events on enzalutamide and abiraterone acetate plus prednisone treatment
P. Ruiz Gracia et al.
Results: RR for hypertension (all grades) was 2.26 (1.06-4.81) for ENZ and 1.61 (1.30-2.00) for AA + P, for hypertension grade ≥ 3 was 2.52 (1.61-3.95) and 1.72 (0.97-3.06) respectively. The RR for neurological disorders was 1.44 (1.31-1.58) for ENZ and 1.13 (0.99-1.29) for AA + P. RR for psychiatric disorders was 1.43 (1.21-1.69) for ENZ and 1.04 (0.9-1.20) for AA + P. No evidence of publication bias was observed.
Conclusions: The aim of this study is to contrast the hypertension, psychiatric and central nervous system disorders safety profile of AA + P and ENZ. This analysis suggests that mCRPC patients treated with ENZ had a higher risk of developing hypertension, neurological and psychiatric disorders than the patients treated with AA + P. One may speculate that the affinity of ENZ for GABA receptor may play a role in the toxicities related to the central nervous system.
CARE Faculty Perspective:
Selecting a therapy for patients with mCRPC is challenging, and there are many factors to consider, including safety (ie. adverse events/toxicities) and efficacy.
This meta-analysis found a higher level of toxicities related to the CNS (neurological & psychiatric disorders) as well as hypertension with enzalutamide vs. abiraterone
Based on a patient’s individual fitness level, age, comorbidities, etc., this slight increase in toxicities is something to consider when choosing a therapy for a patient with mCRPC.