Ascentage Pharma Presents Pivotal China Registrational Study Data for Lisaftoclax in Oral Report at 2025 American Society of Hematology (ASH) Annual Meeting

Rhea-AI Summary

Ascentage Pharma (NASDAQ: AAPG) presented registrational Phase II China data for lisaftoclax (APG-2575) at ASH 2025 showing durable efficacy in BTKi‑refractory relapsed/refractory CLL/SLL.

Among 77 enrolled patients (high‑risk enrichment: 42.9% complex karyotype, 39% del(17p)/TP53), lisaftoclax achieved an IRC‑confirmed ORR 62.5% and median PFS of 23.89 months (median follow‑up 22.01 months). MRD negativity was 21.8% in peripheral blood and 54.5% in bone marrow (n=11). Safety showed manageable profile with frequent grade ≥3 hematologic toxicities; no tumor lysis syndrome or treatment‑related deaths were reported. The data supported China NMPA approval in July 2025.

Positive

• ORR 62.5% in evaluable BTKi‑refractory patients
• Median PFS 23.89 months (median follow‑up 22.01 months)
• China NMPA approval July 2025 supported by registrational data
• Bone‑marrow MRD negativity 54.5% (11 evaluable patients)
• High‑risk enrollment: 42.9% complex karyotype

Negative

• Frequent grade ≥3 hematologic treatment‑related adverse events
• Single‑arm Phase II N=77 limits precision for subgroups

Key Figures

Objective response rate 62.5% Registrational Phase II in 72 evaluable BTKi-refractory CLL/SLL patients

Median PFS 23.89 months Registrational Phase II lisaftoclax monotherapy, BTK-refractory R/R CLL/SLL

Patients enrolled 77 patients Pivotal Phase II lisaftoclax monotherapy study population

Complex karyotype 42.9% Proportion of 77 enrolled patients with chromosomal complex karyotype

del(17p)/TP53 mutation 39% Share of enrolled patients with del(17p)/TP53 mutation

Unmutated IGHV 53.2% Proportion of enrolled patients with unmutated IGHV

Peripheral blood MRD-negativity 21.8% Patients achieving MRD negativity in peripheral blood

Bone marrow MRD-negativity 54.5% Among 11 evaluable patients with bone marrow MRD

Market Reality Check

$32.88 Last Close

Volume Volume 1,459 vs 20-day average 5,076 (relative volume 0.29x) suggests a modest participation move. low

Technical Price 32.88 is trading above the 200-day MA at 31.74, reflecting a pre-existing uptrend.

Peers on Argus

Peers show mixed moves: MIRM -2.17%, ZLAB -3.23%, ACAD +2.58%, ACLX +2.4%, ARWR -2.4%. The +7.17% move in AAPG appears stock-specific to its ASH data.

Historical Context

Date	Event	Sentiment	Move	Catalyst
Dec 04	Phase III clearance	Positive	+1.1%	Global Phase III olverembatinib plus chemotherapy in Ph+ ALL cleared by regulators.
Nov 24	Clinical data publication	Positive	+1.1%	Phase Ib olverembatinib GIST data published showing activity and long median PFS.
Nov 19	Investor conferences	Positive	+0.6%	Announcement of participation in three December investor conferences with management access.
Nov 03	ASH lisaftoclax data	Positive	-3.1%	Preview of ASH data for registrational Phase II lisaftoclax CLL/SLL and combination study.
Nov 03	ASH olverembatinib data	Positive	-3.1%	Announcement of multiple olverembatinib datasets to be presented at ASH 2025.

Pattern Detected

Recent clinically focused announcements tended to see modestly positive reactions, but two ASH-related multi-dataset releases in early November coincided with negative moves, showing occasional divergence on good news.

Recent Company History

Over the last few months, Ascentage Pharma has highlighted multiple late-stage hematology programs. On Nov 3, 2025, it detailed extensive ASH 2025 data for both lisaftoclax and olverembatinib, yet shares fell 3.06% on each of two press releases. Subsequent updates, including an oliverembatinib Phase Ib GIST publication on Nov 24 and a global Phase III clearance in Ph+ ALL on Dec 4, saw modest gains. Today’s ASH oral presentation for lisaftoclax in BTKi-refractory CLL/SLL builds directly on the November ASH preview.

Market Pulse Summary

This announcement highlights pivotal Phase II data for lisaftoclax in heavily pretreated, BTKi-refractory CLL/SLL, with an ORR of 62.5% and median PFS of 23.89 months. The study population carried multiple high-risk genomic features, yet responses and MRD-negativity rates remained meaningful. Recent news flow shows a broader late-stage pipeline in hematologic malignancies. Investors may track future global Phase III readouts and regulatory milestones for lisaftoclax and olverembatinib.

Key Terms

objective response rate medical

"Lisaftoclax achieved a 62.5% objective response rate (ORR) in heavily pretreated..."

The objective response rate (ORR) is the percentage of patients in a clinical trial whose tumors measurably shrink or disappear according to preset rules. Investors use it as a quick, objective signal of a drug’s ability to produce a clear treatment effect—like counting how many plants visibly respond after applying a new fertilizer—and higher ORR can improve odds of regulatory approval, commercial success, and company valuation.

progression-free survival medical

"Lisaftoclax monotherapy demonstrated a median progression-free survival of 23.89 months..."

Progression-free survival is the length of time during and after a treatment that a patient's disease does not get worse, measured from the start of treatment until the disease shows measurable signs of progression or the patient dies. Investors care because longer progression-free survival in clinical trials often signals that a drug is effective, improving chances of regulatory approval, market adoption, and revenue potential—think of it as a stopwatch showing how long a therapy can keep the illness at bay.

minimal residual disease medical

"21.8% of patients achieved minimal residual disease (MRD) negativity in peripheral blood."

Minimal residual disease (MRD) is the tiny number of cancer cells that remain in the body after treatment, often too few to show up on standard scans but detectable with very sensitive tests. For investors, MRD is important because it predicts the risk of relapse and can determine whether a therapy is seen as effective, influences regulatory and reimbursement decisions, and affects the size and timing of a drug’s market opportunity—like spotting the last weeds that can make a garden regrow if not removed.

AI-generated analysis. Not financial advice.

• Lisaftoclax monotherapy demonstrated significant and durable clinical efficacy and a manageable safety profile in patients with heavily pretreated BTK-refractory R/R CLL/SLL, underscoring its utility as a potential new treatment option
  
  
• Lisaftoclax achieved a 62.5% objective response rate (ORR) in heavily pretreated, BTKi-refractory patients, nearly half with complex karyotype
  
  
• Lisaftoclax monotherapy demonstrated a median progression-free survival of 23.89 months in patients with heavily pretreated BTK-refractory R/R CLL/SLL, with no tumor lysis syndrome reported
  
  

ROCKVILLE, Md. and SUZHOU, China, Dec. 06, 2025 (GLOBE NEWSWIRE) -- Ascentage Pharma Group International Inc. (NASDAQ: AAPG; HKEX: 6855), a global, commercial-stage, integrated biopharmaceutical company engaged in the discovery, development and commercialization novel, differentiated therapies to address unmet medical needs in cancer, announced that it has presented an oral report featuring the latest results from a registrational Phase II study conducted in China of Lisaftoclax (APG-2575), a key drug candidate in the Company‘s pipeline, as a monotherapy in patients with relapsed/refractory (R/R) chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who had failed Bruton’s tyrosine kinase inhibitors (BTKis), at the 67th American Society of Hematology (ASH) Annual Meeting, being held in Orlando, FL. Data from this pivotal trial supported the NDA approval that was granted to Lisaftoclax by China’s National Medical Products Administration (NMPA) in July 2025.

The ASH Annual Meeting is one of the largest gatherings of the international hematology community, aggregating cutting-edge scientific research and the latest data on investigational therapies that represent leading scientific and clinical advances in the global hematology field. Results from multiple clinical and preclinical studies on three of Ascentage Pharma’s drug candidates --Olverembatinib, Lisaftoclax, and APG-5918 -- have been selected for presentations, including an oral report, at this year’s ASH Annual Meeting, garnering interest from the global research community.

In the data featured in the oral report, Lisaftoclax monotherapy demonstrated durable efficacy and manageable safety in patients with heavily pretreated BTK-refractory R/R CLL/SLL, with no tumor-lysis syndrome (TLS) observed. Notably, among the 77 enrolled patients, 33 (42.9%) had chromosomal complex karyotype, 30 (39%) had del(17p)/TP53 mutation, and 41 (53.2%) had unmutated IGHV. The proportion of patients with these high-risk (HR) factors was higher than in previously published studies involving a medication from this class. Among patients with chromosomal complex karyotype, 63.6% had concurrent chromosomal complex karyotype and 63.6% had concurrent high karyotypic complexity (abnormal chromosome number ≥ 5). Despite this ultra-high-risk profile, Lisaftoclax achieved an objective response rate (ORR) of 62.5% in all evaluable patients, demonstrating strong therapeutic potential.

Lisaftoclax is a proprietary, innovative, orally administered Bcl-2 selective inhibitor being developed by Ascentage Pharma to treat patients with malignancies by selectively blocking the anti-apoptotic protein Bcl-2 and restoring the normal apoptosis process in cancer cells. Lisaftoclax is approved in China for the treatment of adult patients with CLL/SLL who have previously received at least one systemic therapy, including Bruton’s tyrosine kinase (BTK) inhibitors. The Company is currently conducting four global registrational Phase III studies to evaluate Lisaftoclax in multiple indications including CLL/SLL, acute myeloid leukemia (AML), and myelodysplastic syndrome (MDS).

Professor Keshu Zhou, presenter of the study from the Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, commented, “With advances in clinical treatment, some high-risk factors such as del(17p)/TP53 mutation have become increasingly manageable. However, these factors, when coexistent with complex karyotype or ultra high-risk factors such as high karyotypic complexity, have become the most challenging clinical obstacle and adverse prognostic factor in the treatment of CLL/SLL, presenting an urgent clinical need for breakthrough therapies.”

“In this study, nearly half of enrolled patients had complex karyotype and about two thirds of patients with this high-risk factor had concurrent del(17p)/TP53 mutation or high karyotypic complexity,” continued Professor Zhou. “These patients represent an ultra-high-risk subgroup with very poor prognosis. The overall results from the study show that Lisaftoclax monotherapy achieved encouraging deep and durable responses in heavily pretreated patients who had received multiple lines of treatment, especially those who had high-risk factors such as complex karyotype, while also displaying favorable characteristics such as potent efficacy, ease of use, and a favorable safety profile. Lisaftoclax represents a promising strategy for addressing this challenging indication and a beacon of hope for underserved patients with CLL/SLL.”

Yifan Zhai, M.D., Ph.D., Chief Medical Officer of Ascentage Pharma, said, “It is our great honor to present this registrational study of Lisaftoclax at the ASH Annual Meeting, the largest gathering for the international hematology community. In addition to supporting the NDA approval for Lisaftoclax in China, these results also highlighted the differentiated efficacy and safety, as well as the drug’s potential for addressing the urgent unmet clinical need in CLL/SLL globally. Fulfilling our mission of addressing unmet clinical needs in China and around the world, we will strive to accelerate our clinical programs to bring more safe and effective therapies to patients as soon as possible.”

Highlights of the data this study reported at ASH 2025 are as below:

Results of a registrational phase 2 study of lisaftoclax monotherapy for treatment of patients (pts) with relapsed/refractory chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who had failed Bruton’s tyrosine kinase inhibitors (BTKis)

• Format: Oral Presentation
• Abstract#: 88
• Session: 642. Chronic Lymphocytic Leukemia: Clinical and Epidemiological: Treatment of CLL in Relapse and in Richter Transformation
• Time: Saturday, December 6, 2025; 10:15 AM - 10:30 AM EST
• First Author: Professor Keshu Zhou, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China
• Presenter: Professor Keshu Zhou, The Affiliated Cancer Hospital of Zhengzhou University, Henan Cancer Hospital, Zhengzhou, China
• Highlights:
  
  

Background:

Bcl-2 inhibitors play an important role in the treatment of CLL/SLL. Although venetoclax monotherapy was approved in 2016 in the U.S. for the treatment of patients with CLL/SLL who have a 17p deletion [del(17p)]¹, there remains a significant unmet clinical need from patients with CLL/SLL that has failed prior BTKi therapies, especially those who previously received immunochemotherapies (ICTs) that were based on anti-CD20 monoclonal antibodies or had HR factors.

Introduction:
This was a pivotal registrational Phase II study (NCT05147467) in patients with CLL/SLL, with the objective response rate (ORR) as its primary endpoint. Patients in this study were refractory to, relapsed on, or intolerant of both BTK inhibitors and ICTs; or failed prior BTK inhibitors and were ineligible for ICTs.

Patient characteristics at baseline:

• A total of 77 patients were enrolled in this study. Among them, 33 (42.9%) had chromosomal complex karyotype, 30 (39%) had del(17p)/TP53 mutation, and 41 (53.2%) had unmutated IGHV.
• Among patients who had chromosomal complex karyotype, 63.6% had concurrent chromosomal complex karyotype and 63.6% had concurrent high karyotypic complexity (abnormal chromosome number ≥ 5).
  
  

Efficacy Results: As of July 25, 2025, among 72 evaluable patients with R/R CLL/SLL, the ORR as confirmed by the independent review committee (IRC) was 62.5%, the median progression-free survival (mPFS) was 23.89 months (with a median follow-up of 22.01 months). Among high-risk patients (those with adverse prognostic genotypes such as del(17p)/TP53 mutation, chromosomal complex karyotype, and unmutated IGHV), the treatment showed clinically meaningful deep responses. 21.8% of patients achieved minimal residual disease (MRD) negativity in peripheral blood. In the 11 evaluable patients with bone marrow MRD, 54.5% achieved bone marrow MRD negativity.

Safety Results: Lisaftoclax demonstrated a manageable safety profile in BTKi-pretreated patients. Frequent grade ≥3 treatment-related adverse events were hematologic toxicities that included decreased neutrophil count, decreased platelet count, and anemia. Neither tumor lysis syndrome (TLS) nor treatment-related deaths occurred during the study.

Conclusion: Lisaftoclax monotherapy demonstrated significant and durable clinical efficacy and a manageable safety profile in patients with heavily pretreated BTK-refractory R/R CLL/SLL, underscoring its utility as a potential new treatment option.

* Lisaftoclax, Olverembatinib and APG-5918 are currently under investigation and have not yet been approved by the FDA in the U.S.

Reference:

1. Davids MS. Targeting BCL-2 in B-cell lymphomas. Blood. 2017 Aug 31;130(9):1081-1088. doi: 10.1182/blood-2017-04-737338.
   
   

About Ascentage Pharma

Ascentage Pharma Group International (NASDAQ: AAPG; HKEX: 6855) (“Ascentage Pharma” or the “Company”) is a global, commercial stage, integrated biopharmaceutical company engaged in the discovery, development and commercialization of novel, differentiated therapies to address unmet medical needs in cancer. The Company has built a rich pipeline of innovative drug products and candidates that includes inhibitors targeting key apoptotic pathway proteins, such as Bcl-2 and MDM2-p53, as well as next-generation kinase inhibitors.

The lead asset, Olverembatinib, is the first novel third-generation BCR-ABL1 inhibitor approved in China for the treatment of patients with CML in chronic phase (CML-CP) with T315I mutations, CML in accelerated phase (CML-AP) with T315I mutations, and CML-CP that is resistant or intolerant to first and second-generation TKIs. All indications are covered by the China National Reimbursement Drug List (NRDL). The Company is currently conducting a U.S. FDA-cleared, global registrational Phase III trial, or POLARIS-2, of Olverembatinib for CML, as well as global registrational Phase III trials for patients with newly diagnosed Ph+ ALL and SDH-deficient GIST patients.

The Company’s second approved product, Lisaftoclax, is a novel Bcl-2 inhibitor for the treatment of various hematologic malignancies. Lisaftoclax is being commercialized in China following National Medical Products Administration (NMPA) approval for the treatment of adult patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) who have previously received at least one systemic therapy including Bruton’s tyrosine kinase (BTK) inhibitors. The Company is currently conducting four global registrational Phase III trials: the FDA-cleared GLORA study of Lisaftoclax in combination with BTK inhibitors in patients with CLL/SLL previously treated with BTK inhibitors for more than 12 months with suboptimal response; the GLORA-2 study in patients with newly diagnosed CLL/SLL; the GLORA-3 study in newly diagnosed, elderly and unfit patients with acute myeloid leukemia (AML); and the GLORA-4 study in patients with newly diagnosed higher-risk myelodysplastic syndrome (HR MDS), a study that was simultaneously cleared by the U.S. FDA, the EMA of the EU, and China CDE.

Leveraging its robust R&D capabilities, Ascentage Pharma has built a portfolio of global intellectual property rights and entered into global partnerships and other relationships with numerous leading biotechnology and pharmaceutical companies, such as Takeda, AstraZeneca, Merck, Pfizer, and Innovent, in addition to research and development relationships with leading research institutions, such as Dana-Farber Cancer Institute, Mayo Clinic, National Cancer Institute and the University of Michigan. For more information, visit https://ascentage.com/

Forward-Looking Statements

This press release includes forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 and Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. All statements, other than statements of historical facts, contained in this press release may be forward-looking statements, including statements that express Ascentage Pharma’s opinions, expectations, beliefs, plans, objectives, assumptions or projections regarding future events or future results of operations or financial condition.

These forward-looking statements are subject to a number of risks and uncertainties as discussed in Ascentage Pharma’s filings with the SEC, including those set forth in the sections titled “Risk factors” and “Special note regarding forward-looking statements and industry data” in its Registration Statement on Form F-1, as amended, filed with the SEC on January 21, 2025, and the Form 20-F filed with the SEC on April 16, 2025, the sections headed “Forward-looking Statements” and “Risk Factors” in the prospectus of the Company for its Hong Kong initial public offering dated October 16, 2019, and other filings with the SEC and/or The Stock Exchange of Hong Kong Limited we made or make from time to time that may cause actual results, levels of activity, performance or achievements to be materially different from the information expressed or implied by these forward-looking statements. The forward-looking statements contained in this presentation do not constitute profit forecast by the Company’s management.

As a result of these factors, you should not rely on these forward-looking statements as predictions of future events. The forward-looking statements contained in this press release are based on Ascentage Pharma’s current expectations and beliefs concerning future developments and their potential effects and speak only as of the date of such statements. Ascentage Pharma does not undertake any obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

Contacts

Investor Relations:
Stella Yang
Ascentage Pharma
Stella.Yang@ascentage.com
+1 (301) 792-6286

Stephanie Carrington
ICR Healthcare
AscentageIR@icrhealthcare.com
+1 (646) 277-1282

Media Relations:
Sean Leous
ICR Healthcare
AscentagePR@icrhealthcare.com
+1 (646) 866-4012

FAQ

What were lisaftoclax (AAPG) efficacy results reported at ASH 2025?

Lisaftoclax achieved an IRC‑confirmed ORR of 62.5% and median PFS of 23.89 months (median follow‑up 22.01 months).

How many patients in the AAPG lisaftoclax study had high‑risk CLL features?

Of 77 enrolled patients, 42.9% had complex karyotype, 39% had del(17p)/TP53, and 53.2% had unmutated IGHV.

What safety issues were observed with lisaftoclax in the ASH 2025 data?

Treatment showed a manageable safety profile with frequent grade ≥3 hematologic toxicities; no tumor lysis syndrome or treatment‑related deaths occurred.

Did the lisaftoclax Phase II data lead to regulatory approval for AAPG?

Yes; the registrational data supported NMPA approval in China in July 2025 for lisaftoclax in previously treated CLL/SLL.

What were the MRD results reported for AAPG's lisaftoclax at ASH 2025?

Peripheral blood MRD negativity was 21.8%; among 11 evaluable bone marrow samples, 54.5% achieved MRD negativity.