Cesne, Axel Le

In the INTRIGUE phase III trial (ClinicalTrials.gov identifier: NCT03673501 ), adult patients with advanced gastrointestinal stromal tumor previously treated with imatinib were randomly assigned 1:1 to ripretinib 150 mg once daily or sunitinib 50 mg once daily (4 weeks on/2 weeks off). In the primary analysis, overall survival (OS) was immature. In this study, we report the final planned analysis of OS (key secondary end point), progression-free survival (PFS) on third-line therapy (second PFS; prespecified exploratory end point), and long-term safety. Final OS analysis was prespecified to occur with approximately 200 and ≥145 events in the overall and KIT exon 11 intention-to-treat (ITT) populations, respectively. As of March 15, 2023, there were 211 and 151 OS events in the overall ITT and KIT exon 11 ITT populations, respectively. Median OS was similar between second-line ripretinib and sunitinib in both populations (overall, 35.5 v 31.5 months; KIT exon 11, 35.5 v 32.8 months). Median second PFS (on third-line therapy) for the overall ITT population was similar between the ripretinib and sunitinib arms (7.7 v 7.4 months). Safety was consistent with the primary analysis. OS from this analysis was similar between arms, and second PFS suggests that receiving ripretinib did not adversely affect the PFS of third-line therapy.

748 Background: Ripretinib is a switch-control tyrosine kinase inhibitor approved for patients (pts) with gastrointestinal stromal tumor (GIST) who received prior treatment with 3 or more kinase inhibitors, including imatinib. Sunitinib is approved for advanced GIST after imatinib failure. In the second interim analysis of overall survival (OS) from the phase 3 INTRIGUE study, the OS event rate was 41% in the all-patient (AP) intent-to-treat (ITT) population, and OS was similar between treatment arms in both the KIT exon 11 ITT and AP ITT populations. Here, we present the final OS and updated safety from INTRIGUE. Methods: INTRIGUE (NCT03673501) is an open-label, phase 3 study of adults with advanced GIST who had disease progression on or intolerance to imatinib. Randomization was 1:1 to ripretinib 150 mg once daily (QD) or sunitinib 50 mg QD (4 weeks on/2 weeks off) and was stratified by KIT mutational status and imatinib intolerance. OS was a key secondary endpoint (the primary endpoint of progression-free survival was reported previously); final OS analysis was prespecified to occur with ≥200 and ≥145 events in the AP ITT and KIT exon 11 ITT populations, respectively. Data cutoff was March 15, 2023. Results: Of 453 pts, 444 received treatment; 40 remain on treatment (ripretinib, 28/223 [13%]; sunitinib, 12/221 [5%]). Treatment discontinuation was due to progressive disease (PD) by independent radiologic review (56%), PD by investigator (11%), clinical PD (6%), withdrawal of consent (6%), and adverse events (AEs; 5%). Fewer pts discontinued treatment due to AEs with ripretinib vs sunitinib (3% vs 6%). There were 211 OS events (47%) in the AP ITT population and 151 OS events (46%) in the KIT exon 11 ITT population. OS was similar with ripretinib vs sunitinib in the 2 ITT populations (Table). Fewer pts had grade 3/4 treatment-emergent AEs with ripretinib vs sunitinib (43% vs 67%). Dose interruptions and reductions were lower with ripretinib vs sunitinib. Median treatment duration for ripretinib vs sunitinib was 7.9 vs 6.5 months. Conclusions: In the finalOS analysis from the INTRIGUE study, OS was similar between treatment arms. The safety profile remained consistent and more favorable for ripretinib vs sunitinib in pts with advanced GIST previously treated with imatinib. Clinical trial information: NCT03673501 . [Table: see text]

11563 Background: Afami-cel is an autologous, T-cell receptor (TCR) T-cell therapy to treat human leukocyte antigen (HLA) A*02–eligible patients (pts) with advanced solid tumors positive for the cancer testis antigen melanoma-associated antigen A4 (MAGE-A4). The efficacy and safety of afami-cel in pretreated pts with advanced/metastatic synovial sarcoma or myxoid/round cell liposarcoma are being evaluated in the Phase 2, two-cohort, open-label, SPEARHEAD-1 (NCT04044768) trial. Here we report interim overall survival (OS) data in the pts with advanced synovial sarcoma in Cohort 1. Methods: Pts who were HLA-A*02 positive with advanced synovial sarcoma (with evidence of clinical/radiological progression) positive for MAGE-A4 received afami-cel after lymphodepleting chemotherapy containing fludarabine and cyclophosphamide. The primary endpoint was overall response rate per RECIST v1.1 by independent review. Secondary endpoints included OS and progression-free survival (PFS), estimated utilizing the Kaplan-Meier method. Results: As of August 29, 2022, 44 pts with synovial sarcoma received afami-cel (2.68–9.99×109 transduced T-cells) in Cohort 1. The median age was 41 years (range: 19–73 years), 50% of pts were female, 89% of pts were white, 96% of pts were typed as HLA-A*02:01P, and median tumor MAGE-A4 expression H-score was 257 (132–300). Pts were heavily pre-treated with a median of 3 prior lines of therapy (range: 1–12). The median follow-up time at the data cut-off was 20.8 months. Median PFS was 3.8 months (95% CI: 2.8, 5.8) and 4.1 months (95% CI: 2.8, 6.9) by independent and investigator review, respectively. Median OS by independent review was 15.4 months (95% CI: 10.9, not estimable) with 52% of pts censored at the data cut-off. The 12-month OS probability was 60% and 24-month OS probability was 40%. Twenty-one pts received additional therapy during long term follow up (systemic therapy, n = 20; radiation, n = 6; other, n = 4). In the 17 pts who had a RECIST response by independent review, the median OS was not reached, the 12-month OS probability was 90%, and 24-month OS probability was 60%. Conclusions: Pts with advanced synovial sarcoma treated with afami-cel in SPEARHEAD-1 had encouraging survival, especially those pts with a RECIST response. Clinical trial information: NCT04044768 .

e14531 Background: Afami-cel is an autologous, T-cell receptor T-cell therapy engineered to target melanoma-associated antigen A4 (MAGE-A4) in human leukocyte antigen (HLA) A*02–eligible patients (pts) with advanced solid tumors. SPEARHEAD-1 (NCT04044768) is a Phase 2, two cohort, open-label trial to evaluate the efficacy and safety of afami-cel in pretreated pts with advanced/metastatic synovial sarcoma or myxoid/round cell liposarcoma. Here we report data on cytokine release syndrome (CRS) in the pts with advanced synovial sarcoma treated with afami-cel across Cohort 1 and Cohort 2. Methods: Eligible pts had advanced synovial sarcoma and were HLA-A*02 positive with MAGE-A4–positive tumors. Pts received afami-cel after lymphodepleting chemotherapy containing fludarabine and cyclophosphamide. Tocilizumab administration was permitted for Grade 1 CRS if symptoms persisted for ≥ 24 hours or if the pt had co-morbidities, and for Grade ≥2 CRS. Results: As of August 29, 2022, 72 pts with synovial sarcoma received afami-cel (n = 44 Cohort 1; n = 28 Cohort 2). Afami-cel dose range was 1.92–10.00×109 transduced T-cells. The median age was 39.5 years (range: 16–73 years), 47.2% of pts were female, 88.3% of pts were white, and tumor MAGE-A4 expression H-score was 244.5 (range: 66–300). CRS occurred in 72.2% of the pts with synovial sarcoma receiving afami-cel, including Grade 1 in 50% (36/72), Grade 2 in 20.8% (15/72), and Grade 3 in 1.4% (1/72) of pts as per American Society for Transplantation and Cellular Therapy grading. The median time to onset was 2.5 days (range: 1–5 days), and the median time to resolution was 3 days (range: 1 to 14 days). Twenty-seven of 72 (37.5%) pts received at least one dose of tocilizumab. Consistent with expectations, higher serum IL-6 levels were associated with CRS events and the indicated use of tocilizumab for management. RECIST v1.1 responses were observed in pts with and without CRS. Correlation of clinical factors and CRS with response will be presented. Conclusions: CRS was common after afami-cel administration but was mostly low grade. Administration of tocilizumab in SPEARHEAD-1 was effective in the management of CRS. Clinical trial information: NCT04044768 .

11536 Background: Ripretinib is a switch-control tyrosine kinase inhibitor approved for patients (pts) with gastrointestinal stromal tumor (GIST) who received prior treatment with ≥3 kinase inhibitors, including imatinib. Exploratory baseline circulating tumor DNA (ctDNA) next-generation sequencing (NGS) analysis from INTRIGUE showed pts with second-line advanced GIST with primary KIT exon 11 mutations and secondary resistance mutations exclusively in KIT exons 17/18 derived clinical benefit from ripretinib but not sunitinib (Bauer S et al. J Clin Oncol. 2023; Abs 397784). Outcomes in pts with advanced GIST with ctDNA not detected (ctDNA-ND) had not been evaluated. Here, we present exploratory data from INTRIGUE in pts who had baseline ctDNA-ND vs ctDNA detected (ctDNA-D). Methods: INTRIGUE is an open-label, phase 3 study that enrolled pts with advanced GIST who had disease progression on or intolerance to imatinib (NCT03673501). Pts were randomized 1:1 to ripretinib 150 mg once daily (QD) or sunitinib 50 mg QD (4 wks on/2 wks off) and stratified by mutation according to local pathology report. Baseline peripheral whole blood was analyzed by Guardant360, a 74-gene ctDNA NGS-based assay. Pts with ctDNA-D had ≥1 somatic alteration in the 74 genes analyzed. Results: Pts with ctDNA-ND (82/362, 22.7%) were younger (median: 55.5 vs 62.0 years) and had smaller sums of longest diameters of target lesions (median [range]: 57.6 [11–459] vs 108.8 [15–418] mm) vs ctDNA-D (280/362, 77.3%). Progression-free survival (PFS) was longer in pts with ctDNA-ND vs ctDNA-D and numerically higher with ripretinib vs sunitinib in pts with ctDNA-ND (Table). Pts with ctDNA-ND categorized as not having a KIT exon 9 mutation at randomization ( KIT exon 11, other KIT/PDGFRA, or KIT/PDGFRA wild-type; n = 71) had longer PFS with ripretinib vs sunitinib (median not estimable [NE] vs 11 months; HR = 0.56; 95% CI 0.28 to 1.12). Objective response rate (ORR) and overall survival (OS) were higher with ctDNA-ND vs ctDNA-D. Safety was similar between groups and consistent with the primary analysis. Conclusions: Pts with ctDNA-ND had better efficacy outcomes vs pts with ctDNA-D in both treatment arms; PFS was numerically higher with ripretinib vs sunitinib in pts with ctDNA-ND. Although little is known about the biology driving ctDNA in GIST, these data suggest pts may have improved outcomes and different treatment sensitivity based on ctDNA detectability. Clinical trial information: NCT03673501 . [Table: see text]

11524 Background: Ripretinib is a switch-control tyrosine kinase inhibitor approved for patients (pts) with gastrointestinal stromal tumor (GIST) who received prior treatment with ≥3 kinase inhibitors, including imatinib. Sunitinib is approved for advanced GIST after imatinib failure. In the first interim analysis (IA) for overall survival (OS) in the INTRIGUE trial, data were immature (OS event rate, 22.3%), and median OS was not reached in either arm for the KIT exon 11 intent-to-treat (ITT) and all-patient (AP) ITT populations (S Bauer, et al. J Clin Oncol. 2022). Additionally, ripretinib had a more favorable safety profile with fewer grade 3/4 treatment-emergent adverse events (TEAEs) than sunitinib. Here, we present the second IA of OS and updated safety from INTRIGUE. Methods: INTRIGUE is a global, open-label, phase 3 study that enrolled adult pts with advanced GIST who had disease progression on or intolerance to imatinib (NCT03673501). Randomization was 1:1 to ripretinib 150 mg once daily (QD) or sunitinib 50 mg QD (4 wks on/2 wks off) and was stratified by KIT mutational status and imatinib intolerance. OS was a key secondary endpoint; data cutoff for the second IA was Sept 1, 2022. Results: Of 453 pts in the AP ITT population, 444 received treatment; 51 remain on treatment (33/223 [14.8%] with ripretinib and 18/221 [8.1%] with sunitinib). Common reasons for treatment discontinuation were progressive disease (PD) assessed by independent radiologic review (55.4%), PD assessed by investigator (10.6%), clinical PD (5.9%), withdrawal of consent (5.4%), and adverse event (AE; 4.5%); fewer pts discontinued due to an AE for ripretinib vs sunitinib (2.7% vs 6.3%). Following study treatment discontinuation, 58 pts (25.6%) from the sunitinib arm received ripretinib; 139 pts (61.5%) from the ripretinib arm later received sunitinib. There were 185 OS events (40.8%) in the AP ITT population; median duration of follow-up was 28.7 and 28.5 months for ripretinib and sunitinib, respectively. OS was similar with ripretinib vs sunitinib in the AP ITT (median 35.5 vs 30.9 months; HR 0.88, 95% CI 0.66 to 1.18; nominal P = 0.39) and KIT exon 11 ITT populations (median 34.0 vs 31.5 months; HR 1.05, 95% CI 0.75 to 1.48; nominal P = 0.77). The updated safety profile was consistent with the primary analysis; fewer pts had grade 3/4 TEAEs with ripretinib vs sunitinib (95 [42.6%] vs 149 [67.4%]). Dose interruptions and reductions were lower with ripretinib vs sunitinib. The median (range) treatment duration was 7.9 (0.2–38.2) months for ripretinib and 6.5 (0.2–38.3) months for sunitinib. Conclusions: In the second IA from INTRIGUE, OS was similar between treatment arms. The safety profile remained consistent with additional data, and results demonstrate favorable safety with ripretinib in pts with advanced GIST previously treated with imatinib. Clinical trial information: NCT03673501 .

PURPOSE Sunitinib, a multitargeted tyrosine kinase inhibitor (TKI), is approved for advanced gastrointestinal stromal tumor (GIST) after imatinib failure. Ripretinib is a switch-control TKI approved for advanced GIST after prior treatment with three or more TKIs, including imatinib. We compared efficacy and safety of ripretinib versus sunitinib in patients with advanced GIST who were previously treated with imatinib (INTRIGUE, ClinicalTrials.gov identifier: NCT03673501 ). PATIENTS AND METHODS Random assignment was 1:1 to once-daily ripretinib 150 mg or once-daily sunitinib 50 mg (4 weeks on/2 weeks off) and stratified by KIT/ platelet-derived growth factor α mutation and imatinib intolerance. The primary end point was progression-free survival (PFS) by independent radiologic review using modified Response Evaluation Criteria in Solid Tumors version 1.1. Secondary end points included objective response rate by independent radiologic review, safety, and patient-reported outcome measures. RESULTS Overall, 453 patients were randomly assigned to ripretinib (intention-to-treat [ITT], n = 226; KIT exon 11 ITT, n = 163) or sunitinib (ITT, n = 227; KIT exon 11 ITT, n = 164). Median PFS for ripretinib and sunitinib ( KIT exon 11 ITT) was 8.3 and 7.0 months, respectively (hazard ratio, 0.88; 95% CI, 0.66 to 1.16; P = .36); median PFS (ITT) was 8.0 and 8.3 months, respectively (hazard ratio, 1.05; 95% CI, 0.82 to 1.33; nominal P = .72). Neither was statistically significant. Objective response rate was higher for ripretinib versus sunitinib in the KIT exon 11 ITT population (23.9% v 14.6%, nominal P = .03). Ripretinib was associated with a more favorable safety profile, fewer grade 3/4 treatment-emergent adverse events (41.3% v 65.6%, nominal P < .0001), and better scores on patient-reported outcome measures of tolerability. CONCLUSION Ripretinib was not superior to sunitinib in terms of PFS. However, meaningful clinical activity, fewer grade 3/4 treatment-emergent adverse events, and improved tolerability were observed with ripretinib.

PURPOSE Antitumor activity in preclinical models and a phase I study of patients with dedifferentiated liposarcoma (DD-LPS) was observed with selinexor. We evaluated the clinical benefit of selinexor in patients with previously treated DD-LPS whose sarcoma progressed on approved agents. METHODS SEAL was a phase II-III, multicenter, randomized, double-blind, placebo-controlled study. Patients age 12 years or older with advanced DD-LPS who had received two-five lines of therapy were randomly assigned (2:1) to selinexor (60 mg) or placebo twice weekly in 6-week cycles (crossover permitted). The primary end point was progression-free survival (PFS). Patients who received at least one dose of study treatment were included for safety analysis (ClinicalTrials.gov identifier: NCT02606461 ). RESULTS Two hundred eighty-five patients were enrolled (selinexor, n = 188; placebo, n = 97). PFS was significantly longer with selinexor versus placebo: hazard ratio (HR) 0.70 (95% CI, 0.52 to 0.95; one-sided P = .011; medians 2.8 v 2.1 months), as was time to next treatment: HR 0.50 (95% CI, 0.37 to 0.66; one-sided P < .0001; medians 5.8 v 3.2 months). With crossover, no difference was observed in overall survival. The most common treatment-emergent adverse events of any grade versus grade 3 or 4 with selinexor were nausea (151 [80.7%] v 11 [5.9]), decreased appetite (113 [60.4%] v 14 [7.5%]), and fatigue (96 [51.3%] v 12 [6.4%]). Four (2.1%) and three (3.1%) patients died in the selinexor and placebo arms, respectively. Exploratory RNA sequencing analysis identified that the absence of CALB1 expression was associated with longer PFS with selinexor compared with placebo (median 6.9 v 2.2 months; HR, 0.19; P = .001). CONCLUSION Patients with advanced, refractory DD-LPS showed improved PFS and time to next treatment with selinexor compared with placebo. Supportive care and dose reductions mitigated side effects of selinexor. Prospective validation of CALB1 expression as a predictive biomarker for selinexor in DD-LPS is warranted.