Hanmi Pharmaceutical Presents Hematologic Cancer Research at Switzerland's "International Conference on Malignant Lymphoma"

Next-Generation Anticancer Drug Candidate with Dual EZH1/2 Inhibition Mechanism Gains Attention

Hanmi Pharmaceutical has announced research findings indicating that its next-generation targeted anticancer innovative drug candidate, the "EZH1/2 dual inhibitor (HM97662)," currently under development, can overcome the resistance mechanisms associated with existing EZH2-selective inhibitors.

Youngsoo Noh, Director of the ONCO Clinical Team at Hanmi Pharmaceutical (center), explained the poster detailing the research status of HM97662 to attendees, including Dr. Franco Cavalli (fourth from the left), a world-renowned oncologist and president of the ICML conference, at the International Conference on Malignant Lymphoma (ICML 2025) held in Lugano, Switzerland, on the 17th of last month (local time). Hanmi Pharmaceutical

On July 4, Hanmi Pharmaceutical stated that it participated in the 18th International Conference on Malignant Lymphoma (ICML 2025), held in Lugano, Switzerland, from June 17 to 21, where it presented non-clinical hematologic cancer research findings on HM97662 in a poster session.

HM97662 is being developed as a next-generation innovative targeted therapy that, through a "dual inhibition mechanism" targeting both EZH1 and EZH2 proteins simultaneously, demonstrates superior anticancer efficacy and the potential to overcome resistance compared to existing EZH2-selective inhibitors.

EZH1 and EZH2 proteins, often referred to as "genetic regulation switches," play a crucial role in controlling the growth and differentiation of cancer cells. By simultaneously inhibiting these two proteins, it is possible to effectively suppress the function of the cancer-promoting protein complex known as Polycomb Repressive Complex 2 (PRC2), thereby achieving potent anticancer effects.

At this conference, Hanmi Pharmaceutical presented results demonstrating that HM97662 alone exhibited significant tumor growth inhibition in a B-cell lymphoma model. According to the research, HM97662 inhibited the trimethylation of histone protein H3 at lysine 27 (H3K27me3) in a dose-dependent manner more powerfully than tazemetostat (Tazverik), an EZH2-selective inhibitor, in B-cell lymphoma (KARPAS-422) and multiple myeloma (MM1.S) cell lines.

Notably, in resistant cell lines established by prolonged exposure to tazemetostat, an EZH2-selective inhibitor, a compensatory increase in EZH1 protein expression was observed. In animal models with tazemetostat-resistant xenografts derived from these resistant cell lines, HM97662 maintained its antitumor activity.

The company explained that these findings suggest that a dual-targeting strategy inhibiting both EZH1 and EZH2 could represent a new anticancer therapeutic mechanism capable of overcoming the resistance issues seen with existing EZH2-selective inhibitors.

HM97662 is currently undergoing a global Phase 1 clinical trial in Korea and Australia, evaluating the safety and tolerability of single-agent administration in patients with advanced or metastatic solid tumors. Hanmi Pharmaceutical plans to present the results of the global Phase 1 clinical trial of HM97662 at the European Society for Medical Oncology (ESMO 2025) conference scheduled for October.

Youngsoo Noh, Director of the ONCO Clinical Team at Hanmi Pharmaceutical, stated, "It is highly significant that, at this International Conference on Malignant Lymphoma, HM97662 demonstrated differentiated efficacy and the potential to overcome resistance compared to EZH2-selective inhibitors in non-clinical hematologic cancer models." He added, "We expect that expanding indications to various cancer types in the future could present a new paradigm in anticancer therapy."