Nivolumab in Combination with Stereotactic Body Radiotherapy in Pretreated Patients with Metastatic Renal Cell Carcinoma. Results of the Phase II NIVES Study

BACKGROUND

Nivolumab showed an overall survival (OS) benefit in pretreated metastatic renal cell carcinoma (mRCC). The role of stereotactic body radiotherapy (SBRT) in mRCC remains to be defined.

OBJECTIVE

Our aim was to evaluate the efficacy and safety of SBRT in combination with nivolumab in second- and third-line mRCC patients.

DESIGN, SETTING, AND PARTICIPANTS

The NIVES study was a phase II, single-arm, multicenter trial in patients with mRCC with measurable metastatic sites who progressed after antiangiogenic therapy, of whom at least one was suitable for SBRT.

INTERVENTION

The patients received SBRT to a lesion at a dose of 10 Gy in three fractions for 7 d from the first infusion of nivolumab. Nivolumab was given at an initial dose of 240 mg every 14 d for 6 mo and then 480 mg q4-weekly in responding patients.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We hypothesized that nivolumab plus SBRT improves the objective response rate (ORR) compared with nivolumab alone from 25% (derived from historical controls) to 40%. Secondary endpoints were progression-free survival (PFS), OS, disease control rate (DCR) of irradiated and nonirradiated metastases, and safety.

RESULTS AND LIMITATIONS

Sixty-nine patients were enrolled from July 2017 to March 2019. The ORR was 17% and the DCR was 55%. The median PFS was 5.6 mo (95% confidence interval [CI], 2.9-7.1) and median OS 20 mo (95% CI, 17-not reached). After 1.5 yr of follow-up, 23 patients died. The median time to treatment response was 2.8 mo and median duration of response was 14 mo. No new safety concerns arose.

CONCLUSIONS

We did not find sufficient evidence to suggest that nivolumab in combination with SBRT provides an added benefit in pretreated mRCC patients; it should however be evaluated in patients with oligometastatic or oligoprogressive disease.

PATIENT SUMMARY

Nivolumab in combination with stereotactic body radiotherapy does not provide evidence of increased outcomes in metastatic renal cell carcinoma patients. However this approach was safe and showed a good response of the irradiated lesions.

Programmed death ligand-1 (PD-L1) expression in patients (pts) with metastatic renal cell carcinoma (mRCC) treated with nivolumab (NIVO) in combination with stereotactic body radiotherapy (SBRT) in NIVES study

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Background: The NIVES study represents the first prospective trial with NIVO in combination with SBRT in pre-treated mRCC patients. This study did not meet the primary endpoint in terms of objective response rate (ORR) as previously reported. However this combination showed a faster time to treatment response, a long progression free survival and median duration of response without increasing toxicities. Here we have tested with an exploratory analysis the correlation between PD-L1 expression and clinical outcomes in pts treated with NIVO plus SBRT. Methods: PD-L1 expression was assessed in archival collected tumour samples in our central laboratory using 4 commercial kits for immunoistochemical (ICH) analysis (clone 22C3 pharm DX Dako Agilent, 28.8 Abcam and SP142 and SP263 Ventana Medical System). A tumor cell was considered positive if any membranous staining was found regardless of the intensity. In particular the immunostaining was scored 0 when all tumor cells were unstained (PD-L1-negative), 1+ when < 1% positive tumor cells were counted, 2+ when the percentage was between 1% and 50%,3+ when the number of stained cells was more than 50%. ORR and overall survival (OS) were correlated with PD-L1 staining. Results: Formalin-fixed paraffin-embedded (FFPE) specimens were obtained from 44 of 69 pts enrolled in the NIVES study. Twenty-two pts of 44 (50%) were considered PD-L1-negative using all the 4 commercial kits for ICH analysis, while 14 of 44 pts (31,8%) were defined PD-L1 weakly positive (positive tumor cells < 1% at least in one kit for ICH). Eight of 44 pts (18.1%) were defined PD-L1 strong positive when at least one kit for ICH scored 2+ or 3+. About the correlation between ORR and PDL1 staining in the 42 pts (2/44 pts are not evaluable for ORR), ORR was 18.2% (95% CI, 5.2% to 40.3%) in the PD-L1-negative group vs 20% (95% CI, 5.7% to 43.7%) in weakly/strongly PD-L1 positive (p = 1.00). Among the 44 pts in the intention-to-treat population with available PD-L1 status, median OS was not significantly different between pts with PD-L1 negative (20.56 months, 95% CI, 7.16 to NR) and PD-L1 positive (18.33 months, 95% CI, 6.83 to NR) (p = 0.56). Conclusions: For the first time four commercial kits for ICH analysis were used to test PD-L1 expression in pretreated mRCC pts. Data from these small sample size seem to confirm that PD-L1 in pre-treated mRCC cancer is not a predictive biomarker for selecting pts to receive NIVO-based treatment. Clinical trial information: NCT03469713.

Nivolumab (NIVO) in combination with stereotactic body radiotherapy (SBRT) in pretreated patients (pts) with metastatic renal cell carcinoma (mRCC): First results of phase II NIVES study

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Background: NIVO showed an increased on OS in pre-treated mRCC. The introduction of metastasis SBRT could improve the clinical outcomes. NIVES Study evaluated the efficacy and safety of SBRT in combination with NIVO in II and III line of mRCC pts. Methods: This is a phase II, single arm, multicentre study in mRCC pts with PD after ≤2 prior anti-angiogenic therapies with measurable metastatic sites, and at least one suitable for SBRT. The pts received hypofractionated radiation in 1 lesion at dose of 10 Gy/3 fractions after 7 days from the first infusion of NIVO. NIVO is given as flat dose of 240 mg on day 1 every 14 days for 6 months, then 480 mg q4-weekly in responding pts until PD or unacceptable toxicity. The primary end point is ORR. Secondary endpoints are PFS, OS, ORR of irradiated and non-irradiated metastasis and safety profile. Results: 69 pts were enrolled from July 2017 to March 2019 in 12 Italian centers. Pt characteristics were: 79.7% clear cell histology, 82.6% males, 79.7%% IMDC intermediate/poor, median age 67 yrs (43-85), 18.8% third line, 21.7% non-nephrectomy. The most frequent sites of SBRT were lung (37.7%), lymphonodes (15.9%), bone (11.6%). At the time of this analysis, median number of NIVO doses received was 12 (1-32). The ORR was 19% (1 CR) and DCR 63.5% (no statistically difference between site of SBRT and ORR); the largest benefit in pts with clear cell histology (p=0.01). Median PFS was 4 months (95%CI, 2.8-7.1), median OS 22.1 months (95%CI, 18.1-NR). With a median follow-up of 15 months (0-25.6), 6-month and 9-month survival rates were 80.3% and 56.1% respectively. 7 pts (10.1%) discontinued treatment due to AEs; grade(G) 3-4 toxicities related to NIVO were experienced in 17 pts (24.6%). The most frequent G3-4 toxicities included diarrhea (5.8%), amylase/lipase increased (4.3%) and hypothyroidism (4.3%); no G3-4 toxicities related to SBRT. Conclusions: The NIVES Study represents the first prospective trial of NIVO and SBRT combination in pre-treated mRCC pts. At present the Study showed a high DCR and no-increase of toxicity. It is ongoing the analysis of correlation between efficacy and PD-L1 expression. Clinical trial information: NCT03469713.