Biosight Presents Updated New Clinical Data from Ongoing Phase 2b Study of Aspacytarabine (BST-236) at the 2020 ASH Annual Meeting

AIRPORT CITY, Israel, Dec. 07, 2020 (GLOBE NEWSWIRE) -- Biosight Ltd., a pharmaceutical development company developing innovative therapeutics for hematological malignancies and disorders, today announced the presentation of updated clinical data from the Company’s ongoing Phase 2b trial evaluating aspacytarabine (BST-236) as a single-agent first-line acute myeloid leukemia (AML) therapy for patients unfit for standard chemotherapy at the 62^nd American Society of Hematology (ASH) Annual Meeting and Exposition.

“These exciting data provide additional evidence that aspacytarabine has the potential to transform standard of care for AML patients,” said Jessica K. Altman M.D., Professor, Medicine, Feinberg School of Medicine of Northwestern University and Lead Study Investigator. “This larger data set supports our previous encouraging outcomes which are of particular interest given the challenging nature of the patient population treated. The 32% complete remission rate achieved in this population, comprised of mainly secondary AML patients including patients with prior hypomethylating agent therapy, is notable. Importantly, all responders achieved a complete hematological recovery and the MRD(-) rate by flow was 57%. And while still early, these results are important as in responders we are seeing a median duration of response not reached at 12 months, and median overall survival not reached at 24 months. These efficacy results are especially exciting to me as they are achieved in a monotherapy regimen with a limited duration of treatment of up to four courses, and a manageable safety profile.” 

Key presentation highlights:

Poster presentation titled, “Durable Remissions and Increased Overall Survival in AML Patients Deemed Unfit for Standard Intensive Chemotherapy Achieved with High-Dose BST-236 (Aspacytarabine) Induction and Consolidation” presented by Dr. Altman

• 61 patients treated to date across the completed Phase 1/2a and ongoing Phase 2b studies, 39 received the recommended Phase 2 dose of 4.5 g/m²/d, which contains 3 g/m²/d cytarabine. Of them, 35 patients were evaluable for safety and overall survival (OS) analysis, and 31 were evaluable for response analysis
• Baseline patient characteristics include a median age 75, 37% of patients (n=13) ECOG 2, 51% of patients (n=18) with secondary AML, 20% with prior hypomethylating agents (HMA) treatment (n=7) and 40% (n=14) adverse ELN
• Repeated courses of aspacytarabine were well-tolerated in older patients and those deemed unfit for chemotherapy
• Observed adverse events were mainly “on-target” with no cerebellar toxicity, severe mucositis, or renal failure observed
• Complete remission (CR) rates were 32% across all evaluable patients, 43% in de novo AML patients, 24% in secondary AML patients, 14% in patients with prior HMA therapy, and 33% in adverse ELN score patients
• Complete hematological recovery was observed in all CRs with a median time to recovery of 27.5 days
• 57% of evaluable CRs were minimal residual disease negative (MRD(-))
• Duration of response (DOR) was not reached at the end of patient follow up at 12 months, median OS of responders was not reached at 24 months
• Median OS of de novo patients was not reached at 24 months; Median OS of secondary AML patients was 6.8 months

Dr. Ruth Ben Yakar, Chief Executive Officer of Biosight, said, “We are extremely excited by the growing body of evidence that supports the potential of aspacytarabine as a new, highly differentiated treatment option for AML which delivers high-dose chemotherapy with reduced toxicity to patients including those with the greatest need and no satisfying standard of care. Importantly, our results were achieved in patients that are among the most challenging in AML and often excluded from other trials. These results increase our confidence that aspacytarabine may serve as a safer and more tolerable chemotherapy agent with improved efficacy, to provide meaningful benefit beyond current standard of care options broadly across AML patients. We look forward to continued progress with aspacytarabine with completion of enrollment in our ongoing trial expected early next year, while in parallel, expanding to additional Phase 2 trials, including in relapsed/refractory myelodysplastic syndrome (MDS) and AML.”

In addition to being presented at the meeting, the abstract has been selected by members of the Hematology and Aging Committee to be presented in a virtual Poster Walk panel discussion featuring presentation authors and Key Opinion Leaders (KOL) in the field. An audience question and answer session will be held after the KOL panel discussion.

Virtual Poster Walk
Date: Thursday, December 10, 2020, 7:00 AM Pacific Time

About Aspacytarabine (BST-236)
Aspacytarabine is a novel proprietary anti-metabolite. It is composed of cytarabine covalently bound to asparagine, acting as a pro-drug of cytarabine. Cytarabine serves as the backbone of AML therapy for over 40 years due to its superior efficacy, however, it is associated with severe bone marrow, gastrointestinal, and neurological toxicities, which significantly limit its use, especially in older and medically compromised patients. Due to its unique pharmacokinetics and metabolism, aspacytarabine enables high-dose therapy with lower systemic exposure to free cytarabine and relative sparing of normal tissues. As such, aspacytarabine may serve as a superior therapy for AML and other hematological malignancies and disorders, including for older adults who are unfit for intensive therapy.

Aspacytarabine was granted FDA Fast Track Designation for first-line treatment of AML patients unfit for standard chemotherapy, and Orphan Drug Designation, which entitles Biosight to seven years of market exclusivity upon aspacytarabine marketing approval for the treatment of AML.

A Phase 2b study is ongoing to confirm the promising results obtained in a Phase 1/2a study of aspacytarabine as a single-agent first-line AML therapy. For more information regarding the Phase 2b clinical study of BST-236, please visit www.clinicaltrials.gov.

About Biosight Ltd.
Biosight is a private Phase 2 clinical stage biotech company developing innovative therapeutics for hematological malignancies and disorders. Biosight’s lead product, aspacytarabine (BST-236), is an innovative proprietary anti-metabolite which addresses unmet medical needs by enabling high-dose chemotherapy with reduced systemic toxicity. Aspacytarabine is currently being investigated as a single agent in a Phase 2b for first-line treatment of acute myeloid leukemia (AML), following completion of a Phase 1/2a study which demonstrated tolerability with promising efficacy in the challenging population of AML patients unfit for standard of care chemotherapy. A Phase 2 study in relapsed/refractory AML and myelodysplastic syndrome (MDS) will be launched in 2020 under a collaboration agreement recently signed with the European cooperative group, GFM. For additional information, please visit www.biosight-pharma.com.

Contact:
Chuck Padala
646-627-8390
LifeSci Advisors, LLC