Efficacy and safety of motesanib, an oral inhibitor of VEGF, PDGF, and Kit receptors, in patients with imatinib-resistant gastrointestinal stromal tumors (original) (raw)

The outcome and predictive factors of sunitinib therapy in advanced gastrointestinal stromal tumors (GIST) after imatinib failure - one institution study

BMC Cancer, 2012

Background: Gastrointestinal stromal tumors (GIST) mutational status is recognized factor related to the results of tyrosine kinase inhibitors therapy such as imatinib (IM) or sunitinib (SU). Arterial hypertension (AH) is common adverse event related to SU, reported as predictive factor in renal cell carcinoma. The aim of the study was to analyze the outcomes and factors predicting results of SU therapy in inoperable/metastatic CD117(+) GIST patients after IM failure. Methods: We identified 137 consecutive patients with advanced inoperable/metastatic GIST treated in one center with SU (2 nd line treatment). Median follow-up time was 23 months. Additionally, in 39 patients there were analyzed selected constitutive single nucleotide polymorphisms (SNPs) of VEGFA and VEGFR2 genes.

Advanced gastrointestinal stromal tumor patients with complete response after treatment with imatinib mesylate

World journal of gastroenterology : WJG, 2006

Most gastrointestinal stromal tumors (GISTs) express constitutively activated mutant isoforms of kit kinase or platelet-derived growth factor receptor alpha (PDGFRA), which are potential therapeutic targets for imatinib mesylate (Glivec). Partial response occurred in almost two thirds of GIST patients treated with Glivec. However, complete response (CR) after Glivec therapy was sporadically reported. Here we illustrated advanced GIST patients with CR after Glivec treatment. Between January 2001 and June 2005, 42 advanced GIST patients were treated with Glivec. Patients were administered 400 mg of Glivec in 100-mg capsules, taken orally daily with food. The response of the tumor to Glivec was evaluated after one month, three months, and every three months thereafter or whenever medical need was indicated. Each tumor of patients was investigated for mutations of kit or PDGFRA. The median follow-up time of the 42 advanced GIST patients treated with Glivec was 16.9 months (range, 1.0-47...

Efficacy and Safety of Regorafenib in Patients With Metastatic and/or Unresectable GI Stromal Tumor After Failure of Imatinib and Sunitinib: A Multicenter Phase II Trial

Journal of Clinical Oncology, 2012

Purpose Metastatic GI stromal tumor (GIST) is a life-threatening disease with no therapy of proven efficacy after failure of imatinib and sunitinib. Regorafenib is a structurally unique inhibitor of multiple cancer-associated kinases, including KIT and platelet-derived growth factor receptor (PDGFR), with broad-spectrum anticancer activity in preclinical and early-phase trials. Because KIT and PDGFR-α remain drivers of GIST after resistance to imatinib and sunitinib, we performed a multicenter single-stage phase II trial of regorafenib in patients with advanced GIST after failure of at least imatinib and sunitinib. Patients and Methods Patients received regorafenib orally, 160 mg daily, on days 1 to 21 of a 28-day cycle. Disease assessment was performed every two cycles per RECIST 1.1. Primary end point was clinical benefit rate (CBR), defined as objective responses (ie, complete or partial response [PR] as well as stable disease [SD] ≥ 16 weeks). Serial tumor biopsies were obtained...

Overview of issues related to imatinib therapy of advanced gastrointestinal stromal tumors: a discussion among the experts

European Journal of Cancer, 2002

Information regarding the activity of imatinib in patients with metastatic gastrointestinal stromal tumors (GISTs) has accumulated rapidly. Nevertheless, several important issues about imatinib therapy as well as these tumors themselves remain to be answered. Importantly, the optimal dose and duration of imatinib therapy are unknown, with daily doses of 400 mg and 600 mg producing comparable response rates in a phase II study. Moreover, the role of surgery following maximal responses to imatinib and those of functional imaging and use of biopsies in monitoring treatment responses need to be investigated. Further understanding of the molecular and pathologic characteristics of GISTs that are responsive or resistant to imatinib is also needed. This paper summarizes a symposium that was held in Helsinki, Finland, in September 2001. 

Effect of KIT and PDGFRA Mutations on Survival in Patients With Gastrointestinal Stromal Tumors Treated With Adjuvant Imatinib: An Exploratory Analysis of a Randomized Clinical Trial

JAMA oncology, 2017

Little is known about whether the duration of adjuvant imatinib influences the prognostic significance of KIT proto-oncogene receptor tyrosine kinase (KIT) and platelet-derived growth factor receptor α (PDGFRA) mutations. To investigate the effect of KIT and PDGFRA mutations on recurrence-free survival (RFS) in patients with gastrointestinal stromal tumors (GISTs) treated with surgery and adjuvant imatinib. This exploratory study is based on the Scandinavian Sarcoma Group VIII/Arbeitsgemeinschaft Internistische Onkologie (SSGXVIII/AIO) multicenter clinical trial. Between February 4, 2004, and September 29, 2008, 400 patients who had undergone surgery for GISTs with a high risk of recurrence were randomized to receive adjuvant imatinib for 1 or 3 years. Of the 397 patients who provided consent, 341 (85.9%) had centrally confirmed, localized GISTs with mutation analysis for KIT and PDGFRA performed centrally using conventional sequencing. During a median follow-up of 88 months (comple...

Molecular Target Modulation, Imaging, and Clinical Evaluation of Gastrointestinal Stromal Tumor Patients Treated with Sunitinib Malate after Imatinib Failure

Clinical Cancer Research, 2009

Purpose: To evaluate sunitinib activity and potential cellular and molecular correlates in gastrointestinal stromal tumor (GIST) patients after imatinib failure, in addition to assessing the safety and pharmacokinetics (PK) of different dose schedules. Experimental Design: In this open-label, dose-ranging, phase I/II study, 97 patients with metastatic imatinib-resistant/intolerant GIST received sunitinib at doses of 25, 50, or 75 mg/d on one of three schedules. Serial tumor imaging was done using computed tomography and [ 18 F]fluoro-2-deoxy-D-glucose positron emission tomography scanning. PK and cell proliferation and KIT phosphorylation status in tumor biopsies were also analyzed. Results: Clinical benefit was observed in 52 patients (54%: 7 objective partial responses, 45 stable disease ≥6 months). Decreased tumor glycolytic activity was shown in most patients within 7 days of starting sunitinib using [ 18 F]fluoro-2-deoxy-D-glucose positron emission tomography. Sunitinib treatment was associated with reduced tumor cell proliferation by >25% in 52% of cases analyzed and reduced levels of phospho-KIT in tumor biopsies (indicating target modulation). The recommended dose schedule was 50 mg/d for 4 weeks followed by 2 weeks off treatment. On the 50-mg dose across all schedules, 79% of PK-evaluable patients achieved total drug trough concentrations above the target concentration (50 ng/mL) within 14 days of dosing. In addition, adverse events were generally mild to moderate in severity. Conclusion: Cellular and molecular analyses showed that sunitinib clinical activity is associated with inhibition of KIT in GIST following imatinib failure, illustrating the rational approach used to develop a therapy aimed at the underlying oncogenic signaling pathway aberrancy. (Clin Cancer Res 2009;15(18):5902-9) Gastrointestinal stromal tumor (GIST) represents an ideal solid tumor model to apply the understanding of aberrant signal transduction to drug discovery and development. Most GISTs (∼95%) express the KIT receptor tyrosine kinase (RTK), and ac-tivating KIT gene mutations represent a key etiologic mechanism in 80% to 85% of GIST patients (1). Approximately 8% of GIST patients have activating mutations in the PDGFRA gene encoding the related RTK platelet-derived growth factor

Correlation of KIT and PDGFRA mutational status with clinical benefit in patients with gastrointestinal stromal tumor treated with sunitinib in a worldwide treatment-use trial

BMC Cancer, 2016

Background: Several small studies indicated that the genotype of KIT or platelet-derived growth factor receptor-α (PDGFRA) contributes in part to the level of clinical effectiveness of sunitinib in gastrointestinal stromal tumor (GIST) patients. This study aimed to correlate KIT and PDGFRA mutational status with clinical outcome metrics (progression-free survival [PFS], overall survival [OS], objective response rate [ORR]) in a larger international patient population. Methods: This is a non-interventional, retrospective analysis in patients with imatinib-resistant or intolerant GIST who were treated in a worldwide, open-label treatment-use study (Study 1036; NCT00094029) in which sunitinib was administered at a starting dose of 50 mg/day on a 4-week-on, 2-week-off schedule. Molecular status was obtained in local laboratories with tumor samples obtained either pre-imatinib, post-imatinib/pre-sunitinib, or post-sunitinib treatment, and all available data were used in the analyses regardless of collection time. The primary analysis compared PFS in patients with primary KIT exon 11 versus exon 9 mutations (using a 2-sided log-rank test) and secondary analyses compared OS (using the same test) and ORR (using a 2-sided Pearson χ 2 test) in the same molecular subgroups. Results: Of the 1124 sunitinib-treated patients in the treatment-use study, 230 (20 %) were included in this analysis, and baseline characteristics were similar between the two study populations. Median PFS was 7.1 months. A significantly better PFS was observed in patients with a primary mutation in KIT exon 9 (n = 42) compared to those with a primary mutation in exon 11 (n = 143; hazard ratio = 0.59; 95 % confidence interval, 0.39-0.89; P = 0.011), with median PFS times of 12.3 and 7.0 months, respectively. Similarly, longer OS and higher ORR were observed in patients with a primary KIT mutation in exon 9 versus exon 11. The data available were limited to investigate the effects of additional KIT or PDGFRA mutations on the efficacy of sunitinib treatment. Conclusions: This large retrospective analysis confirms the prognostic significance of KIT mutation status in patients with GIST. This analysis also confirms the effectiveness of sunitinib as a post-imatinib therapy, regardless of mutational status. Trial registration: NCT01459757.