In:
Journal of Clinical Oncology, American Society of Clinical Oncology (ASCO), Vol. 37, No. 15_suppl ( 2019-05-20), p. 2004-2004
Abstract:
2004 Background: WHO grade II/III gliomas frequently harbor isocitrate dehydrogenase 1 ( IDH1) mutations, resulting in intratumoral accumulation of oncometabolite 2-hydroxyglutarate (2-HG) and subsequent clonal expansion. DS-1001b is an oral selective inhibitor of mutant IDH1 R132X that was designed to penetrate the blood-brain barrier. Methods: In this first-in-human, multicenter, phase I study (NCT03030066), eligible patients (pts) with recurrent/progressive IDH1 mutant glioma received DS-1001b twice daily (bid), continuous. A modified continual reassessment method was used for dose escalation. RANO and RANO-LGG criteria were used to assess tumor response. Pts who planned to undergo salvage surgery after developing progressive disease (PD) and who provided informed consent received DS-1001b treatment until surgery. Tumor samples were also obtained from those pts to measure the free form of DS-1001b and 2-HG levels. Results: Between Jan 2017 and Oct 2018, DS-1001b (125-1400 mg bid) had administered for 45 pts (median age 44 yrs, prior radiation therapy 100%, prior chemotherapy 82%), and 17 pts were continuing treatment. Maximum tolerated dose (MTD) was not reached. Most AEs were Gr 1-2. Gr 3 AEs were observed in 42.2% of pts. No Gr 4 or 5 AEs or serious drug-related AEs were reported. One dose limiting toxicity was Gr 3 white blood cell count decreased (1000 mg bid). Common AEs ( 〉 20%) were skin hyperpigmentation, diarrhea, pruritus, nausea, rash, and headache. Of 29 evaluable pts with contrast enhancing gliomas, one, three and 10 achieved complete response, partial response and stable disease (SD), respectively. Of evaluable nine pts with contrast non-enhancing gliomas, two achieved minor response and seven achieved SD. Peak plasma concentration (Cmax) and area under the curve (AUC) increased dose-dependently. The brain/plasma ratio of free form of DS-1001b ranged 0.19‒0.77 in 3 pts. Conclusions: DS-1001b was well tolerated up to 1400 mg bid with favorable brain distribution, and MTD was not reached. Recurrent/progressive IDH1 mutant glioma pts responded to treatment. Investigation is ongoing to determine the recommended Phase II dose. Clinical trial information: NCT03030066.
Type of Medium:
Online Resource
ISSN:
0732-183X
,
1527-7755
DOI:
10.1200/JCO.2019.37.15_suppl.2004
Language:
English
Publisher:
American Society of Clinical Oncology (ASCO)
Publication Date:
2019
detail.hit.zdb_id:
2005181-5
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