4^th November 2021 – Glycostem Therapeutics B.V., a leading clinical-stage company focused on the development of therapeutic allogeneic off-the-shelf Natural Killer (NK) cells, today announced that the abstract on the initial findings of the first two patients treated in its phase I/IIa WiNK trial have been accepted and will be presented at the 63rd American Society of Hematology Annual Meeting and Exposition (ASH 2021), which will take place 11th – 14th December 2021 in Atlanta, GA, USA. oNKord® is the company’s first-generation off-the-shelf allogeneic NK cell therapy under clinical development. Glycostem is furthermore developing a range of CAR-NK, combination therapy and TCR-NK products in-house.

• Clinical data of the first two acute myeloid leukemia patients enrolled in the phase I/IIa WiNK clinical trial to be presented at the 63^rd American Society of Hematology meeting

• Clearance of measurable residual disease seen in one patient for 6 months and in the second patient for 1 month after a single infusion of oNKord^®, an off-the-shelf NK cell immunotherapy, in the lowest dose cohort

The accepted abstract is published today and available on the ASH website: www.hematology.org.

Title:                    Allogeneic, CD34+, Umbilical Cordblood-Derived NK Cell Adoptive Immunotherapy for the Treatment of Acute Myeloid Leukemia Patients With Measurable Residual Disease

Abstract #:                   1745

Session Name:         704. Cellular Immunotherapies: Clinical: Poster I

Date:                         Saturday, 11^th December 2021

Presentation Time:    5:30 PM - 7:30 PM (EST)

Location:                   Georgia World Congress Center, Hall B5, Atlanta, GA, USA

“We are very excited to share the first clinical data from our WiNK phase I/IIa trial of oNKord^® in patients with Acute Myeloid Leukemia. We are very pleased to see that these first positive results with a single dose infusion with our off-the shelf and allogeneic NK cell product, are confirming our observations from our past clinical trial,” said Kai Pinkernell, MD, Chief Medical Officer of Glycostem.

• The first patient converted to measurable residual disease (MRD) negativity (<0.1%) as assessed by multiparametric flowcytometry (MFC) on bone marrow on day 0, which was sustained at 1, 2, 3 and 6 months. NPM1 MRD, which was detectable by next generation sequencing (MRD-NGS) up to month 1 in peripheral blood (PB), became undetectable by month 2, 3 and 6 in PB (<0.01%VAF). Results in BM showed that NPM1 MRD was detectable at month 1 but was cleared at months 3 and 6.
• The second patient showed MRD positivity in BM by MFC at screening and on day 0, which turned to MRD negativity at month 1, turning positive again at month 2 and 3. Assessments in PB and BM by MRD-NGS showed that a IDH2 and a SRSF2 clone persisted after preconditioning and GTA002 infusion, but that a PTPN11 clone became undetectable in PB by Day 0 and in BM by month 2 and month 3.
• The most recent available follow up will be presented at time of presentation.