A phase II trial combining nivolumab and stereotactic brain radiosurgery for treatment of brain metastases in patients with NSCLC.

Abstract

2023 Background: Previous studies suggested activity of anti-PD-1 in brain metastases from non-small cell lung cancer (NSCLC) and renal cell cancer (RCC). This investigator initiated phase 2 trial examined the safety and efficacy of combining nivolumab with radiosurgery (SRS) in the treatment of patients with brain metastases from NSCLC and RCC. Methods: This is a multicentre open-label trial (NCT02978404) in which patients diagnosed with NSCLC or RCC, having ≤ 10 cc of un-irradiated brain metastases, no whole brain radiotherapy and no prior immunotherapy were eligible. Study treatment commenced with a dose of nivolumab (240mg or 480mg IV), which was continued for up to 2 years at bi-weekly or monthly intervals until progression. SRS (15-21Gy) to all visible un-irradiated brain lesions was administered within 14 days after the first dose of nivolumab (cycle 1). Patients were followed by brain MRI, CT scan of the chest, abdomen and pelvis, neurocognitive and quality of life questionnaires (FACT-Br) every 3 months. The primary endpoint was intracranial progression free survival (icPFS), with death and disease progression within the brain as events. Results from NSCLC patients are presented here. Results: Of the 26 study patients, 22 NSCLC patients were enrolled between Aug 2017 and January 2020. Patients had a median of 2 (1-9) brain metastases. The median diagnosis-specific graded prognostic score was 2 (1-3). Median treatment and follow-up durations were 4.3 months (0-24.8 months) and 11 months (0-24.8 months), respectively. Forty-two percent of the patients had received prior cytotoxic chemotherapy, and 1 patient had received prior brain SRS. PD-L1 status was known for 21 of the 22 NSCLC (12 with ≥50% PD-L1 expression (DAKO 22C3). Median icPFS was 5.0 months (3 intracranial progression and 8 deaths without progression in the brain). Accounting for death as a competing risk, the 1-year cumulative incidence of intracranial relapse was 17.4%. Median extracranial PFS and overall survival were 2.9 months and 14 months, respectively. Four grade 3 adverse events in 2 patients were related to nivolumab or SRS. The rate of survival free of neurocognitive decline (Hopkins Verbal Learning Test total recall) was estimated to be 89% by 4 months. Mean FACT-Br total scores were 89.4 at baseline and improved (p = 0.01) to 139.3 within 2-4 months. Conclusions: Neurocognitive and quality of life assessments suggest that upfront SRS during nivolumab is well tolerated. High intracranial control was observed, but deaths from extracranial disease progression resulted in short icPFS. Studies evaluating the strategic addition of SRS combined with more efficacious systemic treatments are needed. Clinical trial information: 02978404.