Encorafenib plus binimetinib in patients with locally advanced, unresectable, or metastatic BRAFV600-mutant melanoma: Updated data from the multicenter, multinational, prospective, non-interventional longitudinal study BERINGMELANOMA

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Background: For the treatment of advanced BRAFV600-mutated melanoma, targeted BRAF/MEK-inhibition is a standard of care. Encorafenib + binimetinib (EB) were approved 2018 in the EU and 2019 in Switzerland, based on positive results from COLUMBUS (NCT01909453), median progression-free survival (PFS) 14.9 mo (5-yr PFS: 23%), overall survival (OS) 33.6 mo (5-yr OS: 35%). As data from controlled trials are based on selected populations, BERINGMELANOMA investigates EB-use under real-world conditions in a broader population. Methods: BERINGMELANOMA (NCT04045691) is an ongoing, multi-national, prospective, longitudinal, non-interventional study. It analyzes the effectiveness (prim. endpoint: 1-yr PFS-rate), QoL and safety of EB-therapy in the unresectable advanced or metastatic setting under real-world conditions, focusing on the first- (1L) and second-line setting including an evaluation of the impact of prognostic factors. The project aims to enroll up to 750 patients (pts) in a total of 80 German, Austrian and Swiss sites (study duration: 8 yrs). So far (10/2019-01/2022), 280 pts have been included. Pts with prior BRAF-/MEK-inhibition (except adjuvant use completed > 6 mo) and > 1 prior therapy line with CPI in the palliative setting were excluded (adjuvant CPI allowed). Results: Here we present the 2nd planned interim snapshot based on the initial 200 enrolled pts (186 treated / 182 evaluable; median FU: 14.2 mo). This analysis set shows a median age of 60.5 yrs (range 20.0-89.0), 45% of pts were female. 87% presented with distant metastases (brain: 30%), with an involvement of ≥3 organ systems in 51% and elevated LDH in 43%. 54% of pts underwent any prior systemic therapy (adjuvant: 30%; 1L CPI palliative: 24%, mainly with ipilimumab + nivolumab). EB was mainly administered in the 1L-setting (60%). Main reasons for EB-selection were: efficacy (44%), physician's preference (34%), QoL (17%). Median estimated EB treatment duration was 11.6 mo (95%CI 8.8-18.6), median relative dose intensity for both drugs: 100%, main reasons EB-discontinuation: PD (55%), toxicity (16%). Treatment adaptations were required in 40% of pts (interruption E 26%, B 29%), toxicity as main reason (E 26%, B 29%). Adverse events were reported in 86% of pts (grade 3/4: 34%), mainly (≥10%, all grades): diarrhea, nausea, fatigue (each 17%), CK increase (16%), GGT increase (11%). No fatal toxicities were observed. Conclusions: This 2nd interim snapshot shows an investigation of EB in a real-world population with advanced disease. Despite the poorer prognosis configuration as compared to the pivotal study, the observed tolerability profile is largely consistent with data derived from COLUMBUS without any new safety signals. The 3rd interim snapshot will be performed after enrollment of 300 pts.

Encorafenib plus Binimetinib in patients with locally advanced, unresectable or metastatic BRAFV600-mutant melanoma: First data of the multicenter, multinational, prospective, non-interventional longitudinal study BERINGMELANOMA

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Background: For the treatment of advanced BRAFV600-mutated melanoma, targeted therapy (BRAF/MEK-inhibition) is a standard of care. Encorafenib + binimetinib (EB) were approved in the EU in Sep 2018 and in Switzerland in Nov 2019, based on positive results from COLUMBUS (NCT01909453), with a median progression-free survival (PFS) of 14.9 mo (4-year PFS: 26%) and overall survival (OS) of 33.6 mo (4-year OS: 39%). As data from controlled trials are based on selected populations, BERINGMELANOMA investigates the use of EB under real-world conditions in a broader population. Methods: BERINGMELANOMA is an ongoing, multi-national, multi-center, prospective, longitudinal, non-interventional study. It analyzes the effectiveness, quality of life and tolerability of EB-treatment under real-world conditions (primary endpoint: 1-year PFS-rate), focusing on the first- (1L) and second-line setting and including an evaluation of the impact of prognostic factors. The project aims to enroll up to 750 patients (pts) in a total of 80 German, Austrian and Swiss sites with a study duration of 8 yrs. So far, from Oct 2019 to Jan 2021, 153 pts have been included. Pts with prior BRAF-/MEK-inhibition (except adjuvant use completed > 6 mo) and > 1 prior treatment line were excluded. Results: Here we present the first planned interim analysis based on the initial 100 enrolled pts (91 treated / 89 evaluable; median follow-up: 8.1 mo). This analysis set shows a median age of 63.0 yrs (range 29.0-88.0), 52% of pts were female. 81% presented with distant metastases (brain: 31%), with an involvement of ≥3 organ systems in 51% and an elevated LDH in 42%. 54% of pts underwent prior systemic therapy (adjuvant: 28%; 1L: 24%, with ipilimumab + nivolumab as main 1L-treatment: 52%). EB was mainly administered in the 1L-setting (65%). Main reasons for EB-selection were: physician's preference (37%), efficacy (34%), quality of life (21%). Median estimated EB treatment duration was 12.7 mo (95%CI 8.3-NE), median relative dose intensity was 100% for both drugs. Treatment adaptations were required in 34% of pts. Adverse events (AE) were reported in 76% of pts (grade 3/4: 26%). Main AE (≥10%, all grades) were: nausea (18%), diarrhea (17%), CK increase (15%), fatigue (11%), gamma-GT increase (11%). No fatal toxicities were observed. Conclusions: This first interim analysis of BERINGMELANOMA shows an investigation of EB in a real-world population with advanced disease. Despite the poorer prognosis configuration as compared to the pivotal study, the observed treatment duration and tolerability profile are largely consistent with data derived from COLUMBUS without any new safety signals. The second interim analysis will be performed after enrollment of 200 pts and will include an initial analysis of effectiveness data. Clinical trial information: NCT04045691.

The imaging substudy of the randomized ARTE trial: MRI and 18FET PET associations with overall survival benefit from bevacizumab in elderly patients with newly diagnosed IDH wildtype glioblastoma

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Background: Bevacizumab failed to demonstrate overall survival benefit despite markedly prolonged progression-free survival in glioblastoma patients. Reasons for this divergence may include suboptimal patient selection and delayed diagnosis of progression on MRI scans under bevacizumab. Imaging analyses of retrospective and uncontrolled clinical trial cohorts suggest MRI diffusion mapping as a predictor of benefit from bevacizumab. Moreover, amino acid PET has been proposed by the RANO working group for the differentiation of tumor versus edema or gliosis based on proof-of-principle studies demonstrating earlier detection of progression with PET compared to MRI. Methods: ARTE (NCT01443676) was a 2:1 randomized, multi-center, open-label trial of hypofractionated radiotherapy in combination with intravenous bevacizumab every 2 weeks (BEV/RT) versus RT alone in patients with newly diagnosed glioblastoma aged 65 years or older. Patients with histologically and molecularly confirmed IDH wildtype glioblastoma aged 65 years or older were analyzed. MRI was available from 67 and serial 18FET PET from 30 patients in this post hoc analysis. 18FET PET intensity ratios and herein reported MRI parameters including tumor volumetric analyses and ADC were analyzed blinded for outcome and study arm. Results: Demographic, clinical and molecular parameters were balanced between treatment arms. Overall survival benefit from bevacizumab was observed for larger contrast-enhancing tumor volumes (hazard ratio [HR] per cm3 0.94, 95% CI 0.89-0.99, p = 0.032) and higher ADC (HR 0.18, 95% CI 0.05-0.66, p = 0.025) on pre-treatment MRI. Response in the BEV/RT arm by the standard MRI-based RANO criteria was associated with overall survival by trend (HR 0.56, 95% CI 0.30-1.10, time-dependent p = 0.094). In a multivariate model controlling for established risk factors, 18FET tumor-to-brain uptake ratios (TBR) of non-contrast-enhancing tumor portions predicted inferior overall survival specifically in the BEV/RT arm (HR [per 0.1 18FET TBR] 1.50, 95% CI 1.05-2.13, time-dependent p = 0.025). Controlling for 18FET TBR at first follow-up identified benefit from BEV/RT by trend (HR 0.41, 95% CI 0.16-1.07, p = 0.069). Conclusions: Large contrast-enhancing tumor mass and high ADC identify patients with overall survival benefit from bevacizumab. Under bevacizumab, non-contrast enhancing tumor portions can be adequately monitored by amino acid PET.

Incidence of hypocalcemia in patients with castration-resistant prostate cancer treated with denosumab: Data from a non-inferiority phase III trial assessing prevention of symptomatic skeletal events (SSE) with denosumab administered every four weeks (q4w) versus every 12 weeks (q12w)—SAKK 96/12 (REDUSE)

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Background: DN given q4w has shown superiority in delaying skeletal related events over q4w zoledronic acid (ZA). Recently it has been demonstrated that ZA q12w is non-inferior to ZA q4w. The objective of REDUSE is to show non-inferiority for DN q12w versus q4w in terms of SSE. Here we present an interim analysis for the secondary endpoint HC. Methods: Patients (pts) with castration resistant prostate cancer (planned N=690) were randomized 1:1 to DN q4w (Arm A) vs q12w (Arm B) after a 16 week induction phase with application q4w. All pts received vitamin D (ViD) 400 U and calcium (Ca) 500 mg daily. Measurement of corrected serum-Ca was mandatory before each DN injection. This interim analysis was performed after 3.5 years of accrual. Men who received ≥ 1 dose of DN were considered evaluable. Results: 383 pts were evaluable. HC occurred in 28.7% during the first 16 weeks (DN q4w for all pts) and 30.2% afterwards. After the induction phase HC occurred in 40.2% in Arm A and in 20.3% in Arm B. Grade 3 (2.1%) and 4 (1.1%) HC were rare, most frequently occurring in the first 16 weeks. After 1 year of treatment, the incidence of HC was lower in both arms (A: 30.8%, B: 18.7%). A clinically relevant difference for HC was noted between the two arms after the induction phase (table). Conclusions: In our trial nearly 30% of all men treated with DN experienced HC in the q4w induction phase despite mandatory supplementation of calcium and ViD and measurement of Ca. This rate was considerably higher than reported in the registration trials of DN (13%). After induction treatment the incidence of HC is considerably lower in the q12w arm compared to q4w. This suggests that DN given q12w has a more favorable long time toxicity profile (HC) compared to DN q4w. Change in HC grade after week 16 (week 1 – 12: DN q4w Arm A+B), thereafter q4w in Arm A and q12w in Arm B. Clinical trial information: NCT02051218. [Table: see text]