At the ESMO Asia Congress 2025, Henlius announced data readouts from two breast cancer–related studies: results from the phase 3 equivalence study (NCT05346224) of HLX11 (trade name: POHERDY^® in U.S.), the first and only FDA-approved biosimilar to PERJETA^®, and the phase 1 pharmacokinetic (PK) and safety findings of the innovative endocrine therapy HLX78 (lasofoxifene) in healthy Chinese female adults. The data readouts reinforce the Henlius’ comprehensive, full-spectrum strategy in breast cancer and reflects its commitment to advancing high-quality, accessible therapeutic options for patients worldwide.

HLX11 is a pertuzumab biosimilar independently developed by Henlius in accordance with regulatory requirements in China, the EU and the United States. Its indications include neoadjuvant and adjuvant treatment for HER2-positive early breast cancer and treatment of HER2-positive metastatic breast cancer. In November 2025, HLX11 was approved by the U.S. Food and Drug Administration based on a series of comparative clinical studies, including NCT05346224, becoming the first and only pertuzumab biosimilar in the United States with interchangeable designation. Marketing applications have also been accepted for review by the National Medical Products Administration (NMPA), Health Canada and the European Medicines Agency (EMA).

At the Mini Oral session (65MO) of ESMO Asia 2025, the phase 3 equivalence study (NCT05346224) led by Prof. Qiang Liu of Sun Yat-sen Memorial Hospital was presented for the first time. The multicenter, randomized, double-blind, parallel-controlled phase 3 clinical study (NCT05346224) aimed to compare the efficacy and safety of HLX11 with reference Perjeta^® (pertuzumab) as a neoadjuvant therapy in patients with HER2-positive, HR-negative early, or locally advanced breast cancer as part of a complete treatment regimen. Eligible patients were randomized 1:1 to receive either HLX11 or reference Perjeta® (pertuzumab) in combination with trastuzumab and docetaxel every three weeks for four cycles. The primary endpoint of this study was the total pathological complete response (tpCR) rate assessed by Independent Review Committee (IRC).  The secondary endpoints currently being analyzed included tpCR rate assessed by investigators, breast pathologic complete response (bpCR) rate, objective response rate (ORR), event-free survival (EFS), disease-free survival (DFS), safety, pharmacokinetics, and immunogenicity.

Between April 25, 2022 and January 30, 2024, a total of 908 patients were enrolled. HLX11 met the predefined equivalence criteria for tpCR, with a relative risk of 1.01 (90% CI: 0.90–1.14) and a risk difference of 0.47% (95% CI: −5.99%–6.92%) compared with the EU-sourced reference product. Secondary endpoints—including bpCR rates, ORR, EFS—showed consistent trends between the two treatment arms. HLX11 also demonstrated comparable safety, PK and immunogenicity profiles to reference pertuzumab, and no clinically meaningful impact was observed on safety, PK, or risk of immunogenicity from a single transition of treatment from EU-pertuzumab to HLX11.

In the field of endocrine therapy for breast cancer, HLX78 is a clinical-stage oral selective estrogen receptor modulator (SERM) licensed by Henlius from Sermonix Pharmaceuticals, Inc. It has demonstrated robust target engagement in ER+/HER2- metastatic breast cancer, particularly in the presence of estrogen receptor α gene (ESR1) mutations. To date, an international multi-center phase 3 clinical trial of HLX78 in patients with ER+/HER2- metastatic breast cancer and have an ESR1 gene mutation has completed dosing of the first patient in China sites. This clinical trial is currently recruiting subjects in the U.S., Canada, the EU, China, in addition to other countries and regions.

During the Poster Display session (192eP), the phase 1 study of HLX78, led by Dr. Ling Guan from Dongguan People’s Hospital, was presented. This study is a phase 1 study evaluated the PK and safety of a single dose of lasofoxifene in healthy Chinese female adults and compared the results with data previously reported in healthy Japanese and Caucasian adult women. A total of 16 participants received one oral administration of lasofoxifene at 5 mg. No marked differences in drug exposure were observed between pre- or perimenopausal and postmenopausal participants. Besides, no clinically relevant differences in PK of lasofoxifene were observed for the Chinese healthy females in this study when compared cross-trial to data from Japanese and Caucasian healthy females. All treatment-emergent adverse events were Grade 1 or 2, with no Grade ≥3 events reported, demonstrating a favorable safety and tolerability profile.

Henlius has built a robust and diversified breast cancer pipeline through both internal innovation and strategic partnerships, covering the full continuum of disease management. Its core product, HANQUYOU (trastuzumab, trade name: HERCESSI™ in the U.S., Zercepac^® in Europe), has been approved in more than 50 countries and regions worldwide; neratinib (HANNAIJIA), a HER2-positive extended adjuvant therapy, strengthens post-surgical risk reduction when used sequentially after trastuzumab; POHERDY^® is the first and only pertuzumab biosimilar approved in the U.S.; and the company’s CDK4/6 inhibitor FUTUONING (fovinaciclib citrate) has been approved in China for first- and second-line treatment of HR+/HER2- advanced breast cancer. In parallel, Henlius is accelerating development of multiple high-potential innovative assets, including novel-epitope HER2 antibody HLX22, endocrine therapy candidate lasofoxifene HLX78, KAT6A/B inhibitor HLX97, LIV-1-targeting ADC HLX41, HER2×HER2 biparatopic ADC HLX49, and HER2 ADC HLX87. The company aims to strengthen its synergistic pipeline and build an end-to-end therapeutic ecosystem covering the entire disease course, bringing comprehensive solutions to breast cancer patients worldwide.