Davis, Lara E

Abstract Background Regorafenib is one of several FDA‐approved cancer therapies targeting multiple tyrosine kinases. However, there are few subtype‐specific data regarding kinase inhibitor activity in sarcomas. We report results of a single arm, phase II trial of regorafenib in advanced Ewing family sarcomas. Methods Patients with metastatic Ewing family sarcomas (age ≥ 18, ECOG 0–2, good organ function) who had received at least one line of therapy and experienced progression within 6 months of registration were eligible. Prior kinase inhibitors were not allowed. The initial dose of regorafenib was 160 mg oral days 1–21 of a 28‐day cycle. The primary endpoint was estimating progression‐free rate (PFR) at 8 weeks employing RECIST 1.1. Results Thirty patients (median age, 32 years; 33% women [10 patients]; bone primary, 40%; extraskeletal primary, 60%) enrolled at 14 sites. The most common grade 3 or higher toxicities were hypophosphatemia (5 grade 3, 1 grade 4), hypertension (2 grade 3), elevated ALT (2 grade 3). Sixteen patients required dose reductions, most often for hypophosphatemia ( n = 7 reductions in 6 patients); two stopped regorafenib for toxicity. There was one death unrelated to treatment in the 30‐day post‐study period. Median progression‐free survival (PFS) was 14.8 weeks (95% CI 7.3–15.9); PFR at 8 weeks by Kaplan–Meier analysis was 63% (95% CI 46–81%). The RECIST 1.1 response rate was 10%. Median OS was 53 weeks (95% CI 37–106 weeks). Conclusions Regorafenib has modest activity in the Ewing family sarcomas. Toxicity was similar to that seen in approval studies.

AbstractBackgroundSarcomas are rare diagnoses but are seen with relative frequency in adolescents and young adults and thus can present in pregnancy. We sought to study the administration of anthracyclines and/or ifosfamide in pregnancy‐associated sarcomas.Patients and MethodsWe conducted a multi‐institutional retrospective study, identifying sarcoma patients who received anthracyclines and/or ifosfamide during pregnancy. Chart review identified variables related to demographics, cancer diagnosis, therapies, and outcome of the patient and fetus. Wilcoxon rank‐sum test compared two independent samples.ResultsWe identified 13 patients at seven institutions with sarcoma who received anthracyclines and/or ifosfamide during pregnancy, including four bone sarcomas and nine soft tissue sarcomas diagnosed at a mean gestational age of 16.7 ± 5.9 weeks. Only nine patients had live births (9/13, 69.2%), with mean gestational age of 30.8 ± 3.8 weeks at delivery. The four patients with pregnancy loss all received both doxorubicin and ifosfamide, with chemotherapy initiated at 15.5 weeks as compared with 21.3 weeks for those patients with live births (p = 0.016).ConclusionIn this multi‐institutional study of sarcoma chemotherapy regimens administered during pregnancy, we found a high rate of fetal demise that was seen only in patients receiving both doxorubicin and ifosfamide and statistically more likely with chemotherapy initiation earlier in the second trimester. While limited by a small sample size, our study represents the largest study of sarcoma patients that received anthracyclines and/or ifosfamide in pregnancy thus far reported and supports development of an international registry to study concerns raised by our study.

Abstract Trial Information Click here to access other published clinical trials. Lessons Learned The results from the liposarcoma cohort of SARC024 confirm previously published data and do not support the routine use of regorafenib in this patient population. Continued exploration of novel therapies, including combination approaches, is warranted for a patient population in whom limited treatment options exist. Background Regorafenib is a multitargeted kinase inhibitor with a kinase profile overlapping, but distinct from, pazopanib, an agent approved for recurrent and metastatic non-gastrointestinal stromal tumor (GIST), non-adipocytic soft tissue sarcoma. We conducted a randomized, phase II study of regorafenib versus placebo in refractory liposarcoma patients. Methods Patients with advanced or metastatic, treatment-refractory liposarcoma were randomized 1:1 to receive regorafenib 160 mg or placebo once daily (3 weeks on, 1 week off). Patients with well-differentiated liposarcoma only were excluded. Crossover for placebo was allowed upon progression. The primary endpoint was progression-free survival (PFS), according to RECIST version 1.1. Results Forty-eight subjects with liposarcoma (34 dedifferentiated, 12 myxoid/round cell, 2 pleomorphic) were enrolled. Median PFS was 1.87 (95% confidence interval [CI], 0.92–3.67) months for regorafenib versus 2.07 (95% CI, 1.64–3.44) months for placebo; stratified hazard ratio [HR], 0.85 (95% CI, 0.46, 1.58), p = .62. No responses were seen on regorafenib. One PR was observed on placebo. Median overall survival was 6.46 (95% CI, 4.16–23.48) months for regorafenib and 4.89 (95% CI, 3.02–9.77) months for placebo, stratified HR, 0.66 (95% CI, 0.31–1.40), p = .28). Treatment-related adverse events were similar to the known safety profile of regorafenib. Conclusion Regorafenib did not appear to improve PFS in treatment-refractory liposarcoma. No new significant safety signals were observed.

Abstract Purpose: We recently reported a 17.5% objective RECIST 1.1 response rate in a phase II study of pembrolizumab in patients with advanced sarcoma (SARC028). The majority of responses occurred in undifferentiated pleomorphic sarcoma (UPS) and dedifferentiated liposarcoma (DDLPS). We sought to determine whether we can identify immune features that correlate with clinical outcomes from tumor tissues obtained pre- and on-treatment. Patients and Methods: Pretreatment (n = 78) and 8-week on-treatment (n = 68) tumor biopsies were stained for PD-L1 and multiplex immunofluorescence panels. The density of positive cells was quantified to determine associations with anti–PD-1 response. Results: Patients that responded to pembrolizumab were more likely to have higher densities of activated T cells (CD8+ CD3+ PD-1+) and increased percentage of tumor-associated macrophages (TAM) expressing PD-L1 pre-treatment compared with non-responders. Pre-treatment tumors from responders also exhibited higher densities of effector memory cytotoxic T cells and regulatory T cells compared with non-responders. In addition, higher density of cytotoxic tumor-infiltrating T cells at baseline correlated with a better progression-free survival (PFS). Conclusions: We show that quantitative assessments of CD8+ CD3+ PD-1+ T cells, percentage of TAMs expressing PD-L1, and other T-cell densities correlate with sarcoma response to pembrolizumab and improved PFS. Our findings support that multiple cell types present at the start of treatment may enhance tumor regression following anti–PD-1 therapy in specific advanced sarcomas. Efforts to confirm the activity of pembrolizumab in an expansion cohort of patients with UPS/DDLPS are underway.

PURPOSE SARC024 is a phase II clinical trial of the multikinase inhibitor regorafenib in specific sarcoma subtypes, including advanced osteosarcoma. We hypothesized that regorafenib would improve progression-free survival (PFS) in patients with sarcoma and report the results of the osteosarcoma cohort. PATIENTS AND METHODS This trial enrolled patients with progressive metastatic osteosarcoma with measurable disease by RECIST who had received at least one prior line of therapy. Patients were randomly assigned at a ratio of one to one to regorafenib or placebo. Crossover was allowed at time of disease progression. PFS was the primary end point of the study, which was powered to detect a difference of at least 3 months in median PFS. RESULTS Forty-two patients from 12 centers were enrolled between September 2014 and May 2018. Median age was 37 years (range, 18 to 76 years). Patients had received an average of 2.3 prior therapy regimens. Ten patients receiving placebo crossed over to active drug at time of progression. Study enrollment was stopped early, after a data safety monitoring committee review. Median PFS was significantly improved with regorafenib versus placebo: 3.6 months (95% CI, 2.0 to 7.6 months) versus 1.7 months (95% CI, 1.2 to 1.8 months), respectively (hazard ratio, 0.42; 95% CI, 0.21 to 0.85; P = .017). In the context of the crossover design, there was no statistically significant difference in overall survival. Fourteen (64%) of 22 patients initially randomly assigned to regorafenib experienced grade 3 to 4 events attributed to treatment, including one grade 4 colonic perforation. CONCLUSION The study met its primary end point, demonstrating activity of regorafenib in patients with progressive metastatic osteosarcoma. No new safety signals were observed. Regorafenib should be considered a treatment option for patients with relapsed metastatic osteosarcoma.