Clinical outcomes of adjuvant nivolumab in resected stage III melanoma: comparison of CheckMate 238 trial and real-world data.

OBJECTIVES: Nivolumab is approved as adjuvant therapy for resected stage III/IV melanoma based on the phase 3 CheckMate 238 trial. This analysis compared outcomes from CheckMate 238 with those from the real-world Flatiron Health electronic health record-derived de-identified database in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab. MATERIALS: Outcomes included baseline characteristics, overall survival (OS) in the CheckMate 238 cohort (randomization until death or last known alive), and real-world overall survival (rwOS) in the Flatiron Health cohort (nivolumab initiation until death or data cutoff). rwOS was compared with OS using unadjusted and adjusted Cox proportional hazards models. Inverse probability of treatment weighting (IPTW) was combined with the adjusted model to reduce baseline discrepancies. RESULTS: The CheckMate 238 and real-world cohorts included 369 and 452 patients, respectively (median age, 56.0 and 63.0 years; median follow-up, 61.4 vs. 25.5 months). rwOS was not different from OS in the unadjusted (hazard ratio [HR] 1.27; 95% CI 0.92-1.74), adjusted (HR 1.01; 95% CI 0.67-1.54), and adjusted IPTW (HR 1.07; 95% CI 0.70-1.63) analyses. In the adjusted analysis, 2-year OS and rwOS rates were 84%. Median OS and rwOS were not reached. After IPTW, OS and rwOS were not different (HR 1.07; 95% CI 0.70-1.64). CONCLUSIONS: In this comparative analysis, OS in the CheckMate 238 trial was similar to rwOS in the Flatiron Health database after adjustments in patients with resected stage III melanoma (per AJCC-8) treated with adjuvant nivolumab, validating the trial results.

Venous thromboembolism incidence and risk factors associated with immune checkpoint inhibitors among patients with advanced non-small cell lung cancer.

BACKGROUND: Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in patients with lung cancer. Systemic therapies, such as chemotherapy (chemo), are associated with increased risk of VTE. Immune checkpoint inhibitors (ICIs) are a new standard of care for the treatment of lung cancer, but their association with VTE is not fully understood. We evaluated the incidence of VTE and risk factors for patients with advanced non-small cell lung cancer (aNSCLC) treated with first-line ICI-based, chemo-based, or ICI+chemo regimens. METHODS: This retrospective cohort study used HealthCore Integrated Research Environment - Oncology data, an integrated database of administrative claims, coupled with clinical data from a cancer-care quality program. Patients with first-line treatment of stage IV non-small cell lung cancer from July 2014 to August 2020 were grouped based on three treatment types: ICI-based, chemo-based, or ICI+chemo. Patients with VTE before initiation of systemic treatment were excluded. Newly diagnosed VTE events were identified via inpatient and outpatient diagnosis codes. Cox proportional hazards models were used to investigate the factors associated with VTE risk. RESULTS: Among 2299 eligible patients (ICI-based, n=605; chemo-based, n=1092; ICI+chemo, n=602) with a median follow-up of 9.1 months, the VTE incidence rates (95% CI) per 100 person-years were 17.8 (95% CI 16.0 to 19.5) overall, 13.5 (95% CI 10.6 to 16.5) for ICI-based, 18.0 (95% CI 15.5 to 20.5) for chemo-based, and 22.4 (95% CI 20.2 to 24.5) for ICI+chemo. The 6-month cumulative incidence of VTE was 8.1% for ICI-based, 10.9% for chemo-based, and 12.8% for ICI+chemo. Pulmonary embolism was most common, accounting for 63% of the VTE events. After controlling for baseline patient characteristics, the risk of VTE was 26% lower for ICI-based regimens than for chemo-based regimens (HR 0.74, p=0.03). There was no meaningful difference in the risk between ICI+chemo and chemo-based regimens (HR 1.12, p=0.36). Previous radiation and severe obesity (body mass index ≥40) were associated with VTE. CONCLUSIONS: VTE incidence rate per 100 person-years was common across regimens in patients with aNSCLC, but numerically lower for patients receiving ICI-based regimens compared with those receiving chemo-based and ICI+chemo regimens. VTE is a common complication of lung cancer, and there is a continued need for awareness of VTE as a comorbidity in this population.