Ascentage Pharma's First Third-Generation BCR-ABL Inhibitor in China Olverembatinib (HQP1351) Recommended for Breakthrough Therapy Designation

SUZHOU,ChinaandROCKVILLE,Md.,March 24,2021 -- Ascentage Pharma (6855.HK),a globally focused,clinical-stage biotechnology company engaged in developing novel therapies for cancers,chronic hepatitis B (CHB),and age-related diseases,today announcedthat the Center for Drug Evaluation (CDE) of China National Medical Products Administration (NMPA) has recommended the novel candidate drug olverembatinib (HQP1351) of Guangzhou Healthquest Pharma Co.,Ltd,a wholly-owned subsidiary of Ascentage Pharma,for a Breakthrough Therapy Designation (BTD) for the treatment of patients with chronic-phase chronic myeloid leukemia (CP CML) resistant and/or intolerant to first- and second-generation tyrosine kinase inhibitors (TKIs). This BTD recommendation marks another major development for olverembatinib following the Priority Review granted by the CDE in October 2020. The indication of BTD recommendation is an expansion from that of the Priority Review designation.

According to the NMPA's Provisions for Drug Registration (SAMR Order No. 27) and Working Procedures for Review of Breakthrough Therapeutics (No. 82 of 2020) implemented on July 1,2020,the breakthrough therapy review policy is designed to promote the research and creation of drugs with apparent clinical advantages,which are intended for the prevention or treatment of serious life-threatening diseases or diseases which severely impact the qualify of life for which there is no existing treatment or where sufficient evidence indicates advantages of the novel drug over currently available treatment options. Drugs that have been granted the BTD are prioritized by the CDE in communications and exchange,and in receiving guidance to promote the drug development progress. Furthermore,BTD designated drugs will be eligible to the Priority Review status that will accelerate the review process at the stage of application for commercialization. In conclusion,this measure will effectively accelerate the development and review of drugs presenting significant clinical value or addressing urgent clinical needs.

CML is a hematologic malignancy of the white blood cells. Following the commercialization of BCR-ABL TKIs,the treatment of CML has been revamped. However,despite clinical benefits offered by the first-generation BCR-ABL inhibitor imatinib (GLEEVEC®),and several second-generation TKIs,acquired resistance to TKIs remains a major challenge in the treatment of CML. BCR-ABL tyrosine kinase mutations represent a key mechanism of acquired drug resistance; T315I,which is the most common drug-resistant mutation,occurs in about 25% of patients with drug-resistant CML. Patients with T315I-mutant CML are resistant to both first- and second-generation BCR-ABL inhibitors,presenting an urgent unmet medical need for an effective new generation treatment.

Olverembatinib is a novel,orally active,potent third-generation BCR-ABL inhibitor designed to effectively target BCR-ABL mutants,including T315I,and the first China-developed third-generation BCR-ABL inhibitor targeting drug-resistant CML. In July 2019,olverembatinib was cleared by the US Food and Drug Administration (FDA) to enter a Phase Ib clinical study. In May 2020,olverembatinib was granted an Orphan Drug Designation and a Fast Track Designation by the FDA. In October 2020,olverembatinib was granted Priority Review by the CDE in China for the treatment of adult patients resistant to TKI and with T315I-mutant chronic phase CML or accelerated phase CML. In December 2020,clinical trial results of olverembatinib were selected for oral presentation at the American Society of Hematology (ASH) Annual Meeting for the third consecutive year. These data further demonstrated the favorable safety and promising efficacy profiles of olverembatinib.

"Acquired drug resistance to TKIs remains an urgent unmet medical need and a major challenge in the treatment of CML," commented Professor Xiaojun Huang,Director of the Institute of Hematology,Peking University,and the principal investigator of olverembatinib in China. "Currently,no third-generation TKI has been approved in China,and no TKIs approved overseas is expected to enter China anytime soon. Multiple studies of olverembatinib,a China-developed BCR-ABL TKI,have consistently demonstrated promising efficacy and favorable safety in patients with drug-resistant CML,signifying significant potential clinical benefit to the patient population. We hope this BDT will further accelerate the clinical development and the review process for olverembatinib,and ultimately allow patients to soon benefit from this novel therapeutic."

"Olverembatinib is our first candidate drug entering the NDA-stage,and it is expected to become the first approved third-generation BCR-ABL inhibitor in China," said Dr. Yifan Zhai,Chief Medical Officer of Ascentage Pharma. "This BTD for olverembatinib for the treatment of patients with CP CML intolerant or resistant to first- and second-generation TKIs represents the strong recognition of olverembatinib's therapeutic potential in addressing the unmet medical needs in the treatment of CML. Being granted this BTD will strengthen our communication with the CDE,and more importantly,pave the way for a Priority Review designation to the future NDA for this indication,thus accelerate the clinical development and the approval of olverembatinib in China,and help us to make olverembatinib available to patients as early as possible."

About Ascentage Pharma

Ascentage Pharma (6855.HK) is a globally focused,CHB,and age-related diseases. On October 28,2019,Ascentage Pharma was listed on the Main Board of the Stock Exchange of Hong Kong Limited with the stock code: 6855.HK.

Ascentage Pharma focuses on developing therapeutics that inhibit protein-protein interactions to restore apoptosis or programmed cell death. The company has built a pipeline of eight clinical drug candidates,including novel,highly potent Bcl-2,and dual Bcl-2/Bcl-xL inhibitors,as well as candidates aimed at IAP and MDM2-p53 pathways,and next-generation tyrosine kinase inhibitors (TKIs). Ascentage Pharma is also the only company in the world with active clinical programs targeting all three known classes of key apoptosis regulators. The company is conducting more than 40 Phase I/II clinical trials in the US,Australia,and China. HQP1351,the company's core drug candidate developed for the treatment of drug-resistant chronic myeloid leukemia (CML),has been granted an Orphan Drug Designation (ODD) and a Fast Track Designation (FTD) by the US FDA,and a New Drug Application (NDA) for the drug candidate has been submitted and subsequently granted Priority Review by the Center for Drug Evaluation (CDE) in China. To date,Ascentage Pharma has obtained a total of ten ODDs from the US FDA for four of the company's investigational drug candidates.

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