Second line therapy with axitinib after only prior sunitinib in metastatic renal cell cancer: Italian multicenter real world SAX study final results

BACKGROUND

This multi-institutional retrospective real life study was conducted in 22 Italian Oncology Centers and evaluated the role of Axitinib in second line treatment in not selected mRCC patients.

METHODS

148 mRCC patients were evaluated. According to Heng score 15.5%, 60.1% and 24.4% of patients were at poor risk, intermediate and favorable risk, respectively.

RESULTS

PFS, OS, DCR and ORR were 7.14 months, 15.5 months, 70.6% and 16.6%, respectively. The duration of prior sunitinib treatment correlated with a longer significant mPFS, 8.8 vs 6.3 months, respectively. Axitinib therapy was safe, without grade 4 adverse events. The most frequent toxicities of all grades were: fatigue (50%), hypertension (26%), and hypothyroidism (18%). G3 blood pressure elevation significantly correlated with longer mPFS and mOS compared to G1-G2 or no toxicity. Dose titration (DT) to 7 mg and 10 mg bid was feasible in 24% with no statistically significant differences in mPFS and mOS. The sunitinib-axitinib sequence was safe and effective, the mOS was 41.15 months. At multivariate analysis, gender, DCR to axitinib and to previous sunitinib correlated significantly with PFS; whereas DCR to axitinib, nephrectomy and Heng score independently affected overall survival.

CONCLUSIONS

Axitinib was effective and safe in a not selected real life mRCC population. Trial registration INT - Napoli - 11/16 oss. Registered 20 April 2016. http://www.istitutotumori.na.it.

Axitinib after Sunitinib in Metastatic Renal Cancer: Preliminary Results from Italian "Real-World" SAX Study

Axitinib is an oral angiogenesis inhibitor, currently approved for treatment of metastatic renal cell carcinoma (mRCC) after failure of prior treatment with Sunitinib or cytokine. The present study is an Italian Multi-Institutional Retrospective Analysis that evaluated the outcomes of Axitinib, in second-line treatment of mRCC. The medical records of 62 patients treated with Axitinib, were retrospectively reviewed. The Progression Free Survival (PFS), the Overall Survival (OS), the Objective Response Rate (ORR), the Disease Control Rate (DCR), and the safety profile of axitinib and sunitinib–axitinib sequence, were the primary endpoint. The mPFS was 5.83 months (95% CI 3.93–7.73 months). When patients was stratified by Heng score, mPFS was 5.73, 5.83, 10.03 months according to poor, intermediate, and favorable risk group, respectively. The mOS from the start of axitinib was 13.3 months (95% CI 8.6–17.9 months); the observed ORR and DCR were 25 and 71%, respectively. When stratified patients by subgroups defined by duration of prior therapy with Sunitinib (≤ vs. >median duration), there was a statistically significant difference in mPFS with 8.9 (95% CI 4.39–13.40 months) vs. 5.46 months (95% CI 4.04–6.88 months) for patients with a median duration of Sunitinib >13.2 months. DCR and ORR to previous Sunitinib treatment was associated with longer statistically mPFS, 7.23 (95% CI 3.95–10.51 months, p = 0.01) and 8.67 (95% CI 4.0–13.33 months, p = 0.008) vs. 2.97 (95% CI 0.65–5.27 months, p = 0.01) and 2.97 months (95% CI 0.66–5.28 months, p = 0.01), respectively. Overall Axitinib at standard schedule of 5 mg bid, was well-tolerated. The most common adverse events of all grades were fatig (25.6%), hypertension (22.6%), gastro-intestinal disorders (25.9%), and hypothyroidism (16.1%). The sequence Sunitinib–Axitinib was well-tolerated without worsening in side effects, with a median OS of 34.7 months (95% CI 18.4–51.0 months). Our results are consistent with the available literature; this retrospective analysis confirms that Axitinib is effective and safe in routine clinical practice.