Leads Biolabs Reports 21.8-Month PFS for LBL-034 in Myeloma

NANJING, China — October 25, 2026

LBL-034 Shows Activity in Heavily Pretreated Patients

As of July 16, 2026, 56 patients with RRMM had been enrolled in the first-in-human study. Participants had received a median of 4.5 prior lines of therapy, with a range of three to 12 lines. The population included patients with substantial prior treatment exposure and high-risk disease characteristics. Approximately 73.2% were exposed to three major drug classes, 57.1% had received five drug classes, and 60.7% were refractory to three major treatment classes. In addition, 28.6% had undergone autologous stem-cell transplantation, while 16.1% had previously received BCMA-directed CAR T-cell therapy. High-risk features were also common: 23.2% of participants had EMD, and 64.3% had high-risk cytogenetic abnormalities. Within the effective dose range of 400–1,200 μg/kg, LBL-034 achieved an overall median PFS of 21.8 months, with the 15-month PFS rate reaching 62.0% and the 18-month rate reaching 54.8%. Median duration of response had not been reached, indicating that the response-duration analysis remained ongoing. The reported duration-of-response rates were 77.0% at 12 months and 68.4% at 18 months. The company also observed a dose-dependent trend in the time required to achieve complete response (CR) or better. Median time to CR or better decreased from 5.60 months at 400 μg/kg to 3.45 months at 800 μg/kg and 3.06 months at 1,200 μg/kg. Leads Biolabs said this trend provided pharmacodynamic support for selecting a recommended Phase 2 dose. The subgroup results were notable given the treatment histories and disease features of the enrolled patients. Nevertheless, subgroup findings from a small, early-phase study should be interpreted cautiously, particularly where the number of patients in each subgroup is limited.

Responses in High-Risk Subgroups and Manageable Safety

LBL-034 demonstrated reported antitumor activity in several difficult-to-treat RRMM subgroups. Among patients with extramedullary disease, the overall response rate (ORR) was 75.0%, including two patients who achieved stringent complete response (sCR). In the 1,200 μg/kg cohort, all patients with EMD responded, corresponding to an ORR of 100%, with reported reductions in extramedullary lesions. Among patients whose disease had failed previous BCMA-targeted therapy, the ORR was 85.7%, and the sCR rate was 57.1%. In patients exposed to five drug classes, the ORR was 73.9%, with an sCR rate of 34.8%. These findings suggest potential activity in populations with limited treatment options, although further research is required to confirm response durability and determine how the candidate compares with available therapies. The safety profile was described as manageable across the evaluated dose range. No DLTs were observed during dose escalation up to 1,200 μg/kg, and the maximum tolerated dose was not reached. Nearly all reported CRS events were low-grade, with only one Grade 3 or higher event. Two cases of ICANS were reported, and both patients recovered fully. No movement disorders or ataxia-related neurotoxic events were observed in the reported data. Treatment-emergent adverse events affecting quality of life were predominantly Grade 1 or 2. The company reported that most adverse events occurred during step-up dosing and the first treatment cycle, with event rates declining substantially in subsequent cycles. Median treatment exposure was 11.3 months, providing additional information about treatment duration in the study population. These findings support continued safety monitoring as development progresses, particularly because T-cell-engaging therapies can produce immune-mediated adverse events. The available results do not eliminate the possibility of less common or delayed toxicities emerging with larger patient numbers or longer follow-up.

Leads Biolabs Advances Its LeadsBody TCE Platform

LBL-034 is designed to engage GPRC5D on multiple myeloma cells and CD3 on T cells, bringing immune effector cells into proximity with malignant cells to promote targeted immune activity. The candidate is part of Leads Biolabs’ proprietary LeadsBody platform, which is intended to support the development of T-cell-engaging molecules. According to the company, the updated first-in-human findings represent the first clinical validation of the platform. Chief Medical Officer Dr. Charles Cai said the responses observed in heavily pretreated patients, including those with EMD and prior BCMA-targeted treatment failure, support further investigation of LBL-034. He also highlighted the dose-dependent trend in time to complete response or better and the concentration of adverse events in early treatment cycles. The company intends to use the findings to advance its TCE pipeline and explore potential applications beyond hematologic malignancies, including solid tumors and autoimmune diseases. Those broader applications remain development objectives rather than established clinical uses of LBL-034. The current evidence is based on an early-phase study with 56 enrolled patients overall and 41 patients in the reported effective dose range. The median PFS estimate was still immature at the cutoff, and median duration of response had not been reached. Larger studies and longer follow-up will be needed to clarify the candidate’s benefit-risk profile, confirm its activity in high-risk subgroups and establish the appropriate dose for subsequent trials. LBL-034 remains investigational and is not approved for commercial use. The ESMO 2026 results provide an update on its clinical development and support continued evaluation of GPRC5D/CD3 T-cell engagement as a treatment strategy for RRMM.

Source:Leads Biolabs ,Press release