Ascentage Pharma to Initiate Phase Ib Study of HQP1351 in Tyrosine Kinase Inhibitors -resistant Chronic Myeloid Leukemia Patients in the US

SUZHOU,China and ROCKVILLE,Md.,July 22,2019 --Ascentage Pharma,a globally-focused,clinical-stage biotechnology company engaged in developing novel therapies for cancers,hepatitis B virus and age-related diseases,today announced that the company was notified by the U.S. Food & Drug Administration (FDA) on the clearance of the Investigational New Drug (IND) application which allows the company to initiate its Phase Ib clinical trial of HQP1351,a novel drug candidate developed by Ascentage Pharma,for the treatment of patients with tyrosine kinase inhibitors (TKI)-resistant chronic myeloid leukemia (CML) in the United States.

HQP1351 is the sixth molecule to receive clearance of IND from the FDA for Ascentage Pharma. The Company submitted data generated from over 100 subjects in the Phase I clinical trial in China to the FDA to support the IND application.

This clinical study is a bridging Phase Ib clinical trialwith three dose cohorts (30mg,40mg and 50mg),which is more efficient than the traditional 3+3 dose-escalation study and is expected to accelerate the progress of this clinical trial. It is designed to evaluate the safety,tolerability,and pharmacokinetic (PK) of HQP1351 in CML patients who are resistant or intolerant to at least second-line TKIs and to confirm the recommended Phase II dose (RP2D).This clinical study will be led by Hagop Kantarjian,M.D.,Chair of Department of Leukemia at MD Anderson Cancer Center,and other prominent US research centers and hospitals will also participate.

HQP1351 is designed to address the acquired drug resistance from the treatment using Imatinib. Such resistance is developed in 20-30% of patients treated with the drug develop acquired drugresistance,thus representing a major challenge to the treatment of CML. HQP1351 is an oral,third-generation BCR-ABL TKI targeting a broad spectrum of BCR-ABL mutants,including those with the T315I mutation,to treat drug-resistant CML patients. The agent is currently in pivotal Phase II clinical trial and is the first third-generation BCR-ABL inhibitor targeting drug-resistant CML in China. A New Drug Application (NDA) submission is planned upon the successful completion of the pivotal Phase II clinical studies in China.

As previously announced,the updated data from HQP1351 Phase I study in China was accepted as an oral presentation at the 60th American Society of Hematology (ASH) Annual Meeting last December. The preliminary data showed that HQP1351 was effective in the treatment of first and second generation TKI-resistant CML,especially the highly resistant CML with T315I mutation,with improved safety profile compared to other agents in the same class. This result demonstrates HQP1351's best-in-class potential for treating TKI-resistant CML.

Dr. Yifan Zhai,Chief Medical Officer of Ascentage Pharma,commented: "Ascentage Pharma used the clinical data from its HQP1351 Phase1 clinical trial in China to support the US IND application. This FDA agreed Phase Ib clinical trial design could significantly accelerate HQP1351's global clinical development program. Drug-resistant CML represents significant unmet clinical need and we hope that HQP1351 will soon benefit patients worldwide."

About HQP1351

HQP1351 is a novel kinase inhibitor developed by Ascentage Pharma. It is an oral third-generation BCR-ABL inhibitor targeting a broad spectrum of BCR-ABL mutants,to treat drug-resistant CML patients. A Phase I clinical trial for patients with TKI-resistant CML has been completed and a pivotal Phase II clinical trial was initiated in China. It also entered a Phase I trial in patients with GIST in China.

About Ascentage Pharma Pharma

Ascentage Pharma is a globally-focused,hepatitis B virus and age-related diseases. The Company focuses on developing therapeutics that inhibit protein-protein interactions to restore apoptosis,or programmed cell death. Ascentage Pharma has built a pipeline of eight drug candidates in clinical development,including a novel,highly potent Bcl-2/Bcl-xL inhibitor,as well as candidates aimed at IAP and MDM2-p53 pathways,and next-generation tyrosine kinase inhibitors.