[Edaily Reporter KIM SAE-MI ] LigaChem Biosciences(141080)will present interim results from the Phase 1 clinical trial of its CD19-targeted antibody-drug conjugate (ADC) “IKS03” (LCB73) at the American Society of Hematology (ASH 2026) meeting. Tumor responses were observed in 9 out of 17 evaluable patients, resulting in an objective response rate (ORR) of 53%.

LigaChem Biosciences announced on the 5th that its partner, Exsuda Therapeutics, will present interim results from the Phase 1 clinical trial of IKS03 at the 68th Annual Meeting of the American Society of Hematology, to be held in New Orleans, USA, from the 12th to the 15th of next month (local time).

IKS03 is a CD19-targeted ADC developed using LigaChem Biosciences’ ADC platform, “ConjuAll.” It was designed to utilize a pyrolobenzodiazepine (PBD) prodrug payload that activates selectively within tumors, with the goal of maintaining anticancer efficacy while reducing toxicity to normal tissues.

Iksuda is currently conducting a global Phase 1 clinical trial to evaluate the safety and initial antitumor activity of IKS03 in patients with relapsed or refractory B-cell non-Hodgkin lymphoma who have received two or more prior lines of treatment.

According to the abstract released this time, based on data analyzed last July, responses were confirmed in 9 out of 17 evaluable patients, resulting in an overall response rate (ORR) of 53%. Of these, 5 patients (29%) achieved a complete metabolic response.

Responses were observed in all dose groups, including the lowest dose. Notably, 3 out of 4 patients (75%) who had previously received CD19-targeted chimeric antigen receptor T-cell (CAR-T) therapy also showed a response.

In terms of safety, the maximum tolerated dose (MTD) was not reached, and all treatment-related adverse events were mild or moderate in severity. No Grade 5 adverse events or treatment discontinuations due to adverse events were reported.

Iksuda plans to present updated efficacy and safety data at the conference.

LigaChem Biosciences will also unveil for the first time preclinical results for “LCB122A,” a CD33-targeted ADC currently under development. LCB122A is a candidate drug that employs a DAR1 (drug-to-antibody ratio of 1) structure, in which one drug molecule is bound to each antibody. It is LigaChem Biosciences’ first pipeline to utilize the DAR1 platform.

According to the company, LCB122A demonstrated superior results in preclinical evaluations of anticancer efficacy—including in drug-resistant models—compared to “Mylotarg,” an existing CD33-targeted ADC. The company also stated that toxicity assessments confirmed potential for improvement compared to both Mylotarg and “SGN-CD33A,” a candidate whose development was discontinued.

LigaChem Biosciences plans to proceed with a global Phase 1 clinical trial of LCB122A in patients with relapsed or refractory acute myeloid leukemia (AML).

Park Se-jin, CEO of LigaChem Biosciences, stated, “The excellent clinical results of IKS03 have reaffirmed the competitiveness of the linker-payload system independently developed by LigaChem Biosciences,” adding, “We will continue to generate outstanding clinical outcomes across our extensive pipeline and actively seek technology transfer opportunities.”