Cabozantinib in the elderly with metastatic renal cell carcinoma undergoing geriatric G8 screening test: A prospective multicenter observational study (ZEBRA/MEET-URO 9)

Background: Cabozantinib (CABO) is an oral tyrosine kinase inhibitor registered for the treatment of metastatic renal cell carcinoma (mRCC) for the first or subsequent lines. Tolerability in real world elderly patients is poorly documented. G8 is a short test for vulnerability gaining increased interest as a screening tool for trials in geriatric oncology. Methods: ZEBRA/MEET-URO 9 was a prospective multicenter study of safety and activity of CABO administered to pts ≥70 years with mRCC, either in the first or subsequent lines of treatment, until progression or unacceptable toxicity. All pts underwent G8 score at baseline, with a cut-off for vulnerability of 14 or below. Data on tolerability and activity were collected prospectively after signature of informed consent. Results: A total of 104 pts started CABO at 13 Italian Centers, 38,5% as first line. Median age was 75.8 yrs (range 70.2-87.4 yrs, 26 pts ≥80 yrs), 73.1% males. IMDC score was good 19.2%, intermediate 53.9%, poor 26.9%. Primary tumor had been removed in 82.7% of pts, histology was clear cell 78.8%, papillary 8.7%, chromophobe 5.8%, unclassified 6.7%. G8 score was ≤14 in 65.4% of pts. Up-front dose reduction of CABO was more frequent in pts with low G8 score (79.4 vs 41.7%, p=0.003), but eventually the majority of pts (91.4%) underwent dose reductions of CABO. After a median treatment of 6.4 months (0.5-26.1 months), 38.4% of pts developed G3-4 toxicities, 22.1% interrupted treatment due to adverse events, 2.8% (3 pts) died due to cardiovascular or thromboembolic events. Median PFS was 7.6 months (95% CI=5.8-12.6 months) in first line, 10.0 months (5.8-15.6) in second or further lines, median OS was 20.1 months (11.1-not reached) and 15.6 months (12.5-not reached), respectively. G8 score ≤14 did not correlate with rate of temporary interruptions >7 days, hospitalization, incidence of G3-5 toxicities, as well as with PFS. Pts with G8 score ≤14 had a trend for reduced OS, but difference was not statistically significant both in the first and further lines of treatment. Conclusions: Screening G8 test was positive in more than a half of pts, underlying the need for detailed geriatric assessment and increased clinical monitoring of such patients. A G8 score ≤14 correlated with up-front dose reduction of CABO but not with G3-5 toxicities probably due to the high rates of dose reductions in the whole cohort. Correlation between low G8 score and OS could not be demonstrated in this population

Drug-drug interactions (DDIs) in elderly patients with metastatic renal cell carcinoma (mRCC) treated with cabozantinib within the multicenter prospective trial ZEBRA/Meet-URO 9

Background: The oral tyrosine kinase inhibitor Cabozantinib (CABO) is frequently used to treat patients with metastatic RCC. Polypharmacy is common in elderly pts, thus several drug-drug interactions (DDIs) with cabozantinib may ensue. Methods: ZEBRA /MEET-URO 9 was a prospective, real world trial enrolling pts ≥ 70 years with mRRC treated with CABO at 13 Italian Oncology Centers. All concomitants drugs administered to pts were collected and categorized according to active principles and indication. DDIs were identified through a dedicated software (Lexicomp), scientific databases (Sider4.1) and published articles. Results: we enrolled 104 pts, median age 75.8 years (range 70.2-87.4 yrs). Overall, 91.4% of the cohort was treated at a reduced dose either upfront or due to side effects. Pts took a median of 6 concomitant drugs (IQR: 4-9), for a total of 131 active principles. Software analysis identified 4 DDIs (warfarin, apixaban, diltiazem and furosemide); whereas scientific reports allowed us to identify 15 additional DDIs involving metoprolol, nebivolol, olmesartan, amiloride, simvastatin, rosuvastatin, polyenoic omega-3 fatty acids, loperamide, metoclopramide, metformin, dutasteride, dexamethasone, prednisone, cetirizine and doxazosin. Seventy pts with potential DDIs experienced a trend for higher rate of grade 3-4 adverse events compared to other pts, although difference was not statistically significant (48.7% v 23.5 %, p=0.485). The table summarizes the main DDIs and suggestions to avoid or mitigate their effects Conclusions: the risk of DDIs was not negligible in our cohort of elderly mRCC pts treated with CABO, although the frequent dose reductions of CABO probably confounded their impact on toxicities. Unremitting attention to concomitant medications in the elderly is thus warranted

Prognostic stratification by the Meet-URO score in a real-world elderly population of patients (pts) with metastatic renal cell carcinoma (mRCC) receiving cabozantinib: A subanalysis of the prospective ZEBRA study (Meet-URO 9)

Background: The combination of neutrophil to lymphocyte (NLR), bone metastases and IMDC score in the novel prognostic Meet-URO score has shown a higher prognostic performance than the IMDC score alone in mRCC pts receiving ≥2nd line nivolumab or cabozantinib in two retrospective analyses and 1st line nivolumab-ipilimumab in a real-world prospective study [http://bit.ly/Meet-URO15_score]. Further validation is needed since this score represents an easy prognostic tool for clinical practice with no additional costs. Methods: A real-world analysis of elderly (≥70 yo) mRCC pts treated with any line cabozantinib was conducted in the multicenter observational prospective Zebra study. Baseline Meet-URO score was assessed. The primary endpoint was overall survival (OS) and the Harrell’s c-index was calculated to compare accuracy of survival prediction of the Meet-URO and IMDC scores. Results: 104 mRCC pts received cabozantinib as 1st (38%), 2nd (20%), 3rd (33%) and 4th (8%) line, with a median follow-up of 11.2 months (mo) and a median overall survival (mOS) of 18.4 mo. According to the IMDC score, favorable- (15%), intermediate- (65%) and poor-risk (19%) pts had a mOS not reached (NR), 15.6 and of 5.7 mo, respectively (p = 0.011). Reclassifying the population according to the Meet-URO score, we observed that group 1 (10%) and group 2 (25%) had both mOS NR, whereas group 3 (33%), group 4 (25%) and group 5 (8%) had a mOS of 13.6, 12.5 and 3.7 mo, respectively (p = 0.001). Moreover, the Meet-URO score maintained its discrimination ability also merging group 1-2 vs 3-4 vs 5 (p < 0.001). NLR < 3.2 was the heaviest component of the score (p < 0.001, mOS 24.8 vs 11.5 mo). The Meet-URO score (using both original with 5 groups and modified with 3 groups) has shown a higher prognostic power than the IMDC score alone (c-index of 0.686 and 0.676 vs 0.622). Conclusions: This analysis confirmed the higher accuracy in survival stratification of the Meet-URO score compared with the IMDC score alone also in a specific population like elderly mRCC pts treated with cabozantinib. NLR was confirmed as a strong prognostic factor with cabozantinib. Further applications of the Meet-URO score in mRCC pts treated with first-line immune-combinations are planned and highly awaited

Prognostic Stratification by the Meet-URO Score in Real-World Older Patients With Metastatic Renal Cell Carcinoma (mRCC) Receiving Cabozantinib: A Subanalysis of the Prospective ZEBRA Study (Meet-URO 9)

Background: The addition of neutrophil to lymphocyte ratio (NLR) and bone metastases to the IMDC classification provided by the Meet-URO score, resulted in higher prognostic accuracy in metastatic renal cell carcinoma (mRCC) patients receiving ≥2nd line nivolumab or cabozantinib in 2 retrospective analyses and 1st line nivolumab-ipilimumab in an expanded access programme. Prognostic estimates for older mRCC patients might be key for clinical decision-making. Methods: The outcome of real-world older (≥70 years) mRCC patients treated with any line cabozantinib within the multicenter observational prospective ZEBRA (Meet-URO 9) study was analyzed according to the baseline Meet-URO score. The primary endpoint was overall survival (OS). The discriminative ability by Harrell's c-index and calibration were assessed to compare the Meet-URO and IMDC scores. Results: A total of 104 mRCC patients received cabozantinib as 1st (38%), 2nd (20%), or ≥3rd (41%) line. With a median follow-up of 11.2 months, the median OS (mOS) was of 18.4 months. According to the IMDC score, favorable (15%), intermediate (65%) and poor-risk (19%) patients had a mOS not reached, of 15.6 and 5.7 months respectively (p = .011). According to the Meet-URO score groups, mOS was not reached in both group 1 (10%) and group 2 (25%), while in group 3 (33%), group 4 (25%) and group 5 (8%) mOS was of 13.6, 12.5, and 3.7 months, respectively (p < .001). The discriminative ability of the Meet-URO score was maintained by merging groups 1 to 2 vs. 3 to 4 vs. 5 (p < .001). The Meet-URO score (with either the original 5-group stratification or the modified 3-group one) showed higher accuracy than the IMDC score (c-index of 0.686 and 0.676 vs. 0.622). Conclusion: This analysis confirmed the prognostic accuracy of the Meet-URO score in older mRCC patients treated with cabozantinib and its role as a convenient tool for informing the patient and clinical decisions