2024 ASH Oral Presentation----Abbisko presents promising preliminary phase 2 study results of pimicotinib in the treatment of Chronic Graft-versus-Host Disease (cGvHD) at the 66th ASH Annual Meeting

SHANGHAI,Dec. 9,2024 -- December 8,2024,Abbisko Therapeutics (HKEX: 02256) announced the presentation of preliminary Phase 2 study results for pimicotinib (ABSK021) in patients with chronic Graft-versus-Host Disease (cGvHD) who have either progressed or not responded to one or more prior lines of therapy. The presentation took place at the 66th ASH Annual Conference,held December 7-10,in San Diego,California. Despite most enrolled patients having not yet completed the 6-month treatment cycle required for cGvHD response evaluation,preliminary data from the subset of patients receiving 20mg QD shows that pimicotinib achieved an ORR of 64%.

Prof. Xiaodong Mo,Chief Physician of the Department of Hematology,Peking University People's Hospital,reporting on the scene

As of November 22,a preliminary 64% ORR was observed in the subset of patients receiving pimicotinib 20mg QD,with responses observed in all affected organs,including the gastrointestinal tract,oral cavity,eyes,liver,joints and fascia,esophagus,skin,and lungs.

In many patients with cGvHD,pulmonary manifestations,such as shortness of breath and diminished lung function,can occur and finally be diagnosed as cGvHD-associated BOS (Bronchiolitis Obliterans Syndrome),which is one of the major challenges in the treatment of cGvHD urgently requiring new therapies. During the oral presentation,researchers highlighted specific lung response results in six subjects at the latest data cut-off: one subject achieved an 11% increase in FEV1 (forced expiratory volume in the first second),one subject's FEV1 recovered to more than 75% after treatment thereby returning to normal levels,and the remaining four subjects saw improvements in the NIH Lung score with significant improvements in shortness of breath. Together,data demonstrate the clinical efficacy of pimicotinib for the treatment of cGvHD-associated BOS.

As of the November 22,2024 data cut-off,the majority of enrolled patients have not yet completed the 6-month treatment cycle to determine the primary endpoint of the study,suggesting the possibility of improved outcomes with longer-term treatment with pimicotinib. The results show that pimicotinib demonstrated robust clinical efficacy and is well tolerated in heavily pre-treated patients with cGvHD. Rapid and durable responses were observed across both inflammation-dominated and fibrosis-dominated organs,accompanied by patient-reported reductions in organ-specific symptom burden. The majority of adverse events were Grade 1 and reversible. Based on latest clinical experience,pimicotinib represents a potentially promising and novel therapeutic option for the management of cGvHD.

About Pimicotinib (ABSK021)

Pimicotinib (ABSK021),which is being independently developed by Abbisko Therapeutics,is a novel,orally administered,highly selective,and potent small-molecule inhibitor of CSF-1R. Pimicotinib has been granted breakthrough therapy designations (BTD) by China National Medical Products Administration (NMPA) and the U.S. Food and Drug Administration (FDA) and priority medicine (PRIME) designation from the European Medicines Agency (EMA) for the treatment of patients with TGCT that are not amenable to surgery. Pimicotinib is also currently being evaluated for the treatment of patients with chronic Graft-versus-Host Disease.

About Abbisko Therapeutics

Founded in April 2016,Abbisko Therapeutics Co.,Ltd. (HKEX: 02256.HK),is an oncology-focusedbiopharmaceutical company based in Shanghai that is dedicated to the discovery and development of innovative medicines to treat unmet medical needs in China and globally. The Company wasestablished by a group of seasoned drug hunters with rich research & development and managerial expertise from topmultinational pharmaceutical companies. Since its founding,Abbisko Therapeutics has built an extensive pipeline of innovative programs focused on precision oncology andimmuno-oncology.

Please visit www.abbisko.comfor more information.