809MO - Efficacy and safety results from the phase II study of Timdarpacept in combination with tislelizumab, in prior anti-PD-1 failed classical Hodgkin lymphoma

Background

Timdarpacept (IMM01), a recombinant SIRPa-Fc fusion protein, can activate macrophages to enhance anti-tumor activity by blocking CD47-SIRPa interaction. Timdarpacept showed unique property of weak human erythrocyte binding in preclinical studies, and low incidence of anemia in early clinical trials with no need for a priming dose.

Methods

Eligible patients (pts) with R/R classical Hodgkin lymphoma (cHL) who have failed prior anti-PD-1 treatment were enrolled in this study (NCT05833984). Timdarpacept (2.0mg/kg, QW) and tislelizumab (200mg, Q3W) were intravenously administered in 3-week treatment cycle until disease progression or intolerable toxicity. Objective response rate (ORR) by Lugano 2014 was the primary endpoint and secondary endpoints include tolerability, disease control rate (DCR), duration of response (DoR), progression free survival (PFS) and time to response (TTR).

Results

As of 26 Mar 2024, 33 cHL pts were enrolled. The median age was 35 years. The median prior lines of therapy were 4. In all 33 efficacy evaluable pts with median follow up of 7.03 (4.40, 10.02) month, the ORR, complete response rate and DCR were 66.7%, 24.2% and 93.9%, respectively. The median TTR was 1.6 months. The median PFS was not reached. Further analysis indicated that pts could benefit from Timdarpacept combined with tislelizumab treatment regardless of primary or secondary resistance to anti-PD-1 treatment, or prior CD30-ADC treatment or not. All pts experienced treatment-related adverse events (TRAEs). The most common TRAEs were WBC decreased (51.5%), PLT decreased (42.4%), anemia (39.4%), ANC decreased (36.4%), lymphocyte decreased (30.3%). TRAEs of grade ≥3 occurred in 16 (48.5%) pts, the most common being lymphocyte decreased (30.3%), WBC decreased (15.2%), PLT decreased (12.1%), ANC decreased (12.1%). 4 (12.1%) pts had treatment related SAE. No TRAEs led to the drug discontinuation or death.

Conclusions

Timdarpacept in combination with tislelizumab showed a robust therapeutic efficacy with a well-tolerated safety profile in anti-PD-1 failed cHL patients. The study is ongoing to further evaluate secondary endpoints.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

ImmuneOnco Biopharmaceuticals (Shanghai) Inc., Shanghai, China.

Funding

Has not received any funding.

Disclosure

W. Meng, Z. Wang, Q. Lu: Financial Interests, Institutional, Full or part-time Employment: ImmuneOnco Biopharmaceuticals (Shanghai) Inc. W. Tian: Financial Interests, Personal and Institutional, Leadership Role: ImmuneOnco Biopharmaceuticals (Shanghai) Inc. All other authors have declared no conflicts of interest.