IMM01 (SIRPα-Fc Fusion Protein)

IMM01, our Core Product, is an innovative CD47-targeted molecule. It is the first SIRPα-Fc fusion protein to enter into clinical stage in China. IMM01 designed with IgG1 Fc can fully activate macrophages via a dual mechanism — simultaneously blocking the “don’t eat me” signal by disrupting CD47/ SIRPα interaction and delivering the “eat me” signal through the engagement of activating Fcγ receptors on macrophages. Furthermore, the CD47-binding

domain of IMM01 was specifically engineered to avoid human red blood cell (RBC) binding. With the differentiated molecule design, IMM01 has achieved a favorable safety profile and demonstrated its ability to activate macrophages.

During the Reporting Period and up to the date of this announcement, we have achieved the following progress and milestones:

o Combination Therapy with Azacitidine

◆ The FDA has granted an orphan-drug designation to IMM01 in combination with azacitidine for the treatment of CMML in November 2023.

◆ We have completed the enrollment of patients for the Phase II clinical trial of IMM01 in combination with azacitidine for the first-line treatment of higher-risk MDS in June 2023. 57 patients were enrolled in the study. As of June 30, 2024, among the 51 efficacy evaluable patients, ORR was 64.7% (33/51), including 33.3% of patients (17/51) achieved CR, 15.7% of patients reached mCR with hematologic improvement (HI), 3.9% of patients reached HI and 11.8% of patients reached mCR alone. For patients treated for ≥ 4 months, the ORR reached 85.3% (29/34), and the CRR was 50.0% (17/34). Among patients treated for ≥ 6 months, the ORR reached 89.7% (26/29), and the CRR was 58.6% (17/29), demonstrating increasing efficacy with prolonged treatment duration. Without having to resort to priming dose, the Grade ≥3 hemolysis was rare (only 1.8%). 

◆ A randomized, controlled, double-blind, multicenter, Phase III study (IMM01-009) of IMM01 (Timdarpacept) in combination with azacitidine in patients with newly diagnosed higher-risk MDS was approved by NMPA in May 2024.

◆ We completed the enrollment of patients for the Phase II clinical trial of IMM01 in combination with azacitidine for the first-line treatment of CMML in May 2023. 24 patients were enrolled. As of June 30, 2024, among the 22 efficacy evaluable patients, the ORR was 72.7% (16/22), including 27.3% of patients (6/22) achieved CR, 13.6% of patients reached marrow CR (mCR) with hematologic improvement (HI), 4.5% of patients reached HI and 27.3% of patients reached mCR alone. In patients treated for ≥ 4 months, the ORR reached 87.5%

(14/16), and the CRR was 37.5% (6/16). Among patients treated for ≥ 6 months, the ORR reached 84.6% (11/13), and the CRR was 46.2% (6/13), revealing increasing efficacy with prolonged treatment duration. IMM01, without the use of low-dose priming, combined with azacitidine, was well tolerated in 1L CMML. 

◆ A randomized, controlled, double-blind, multicenter, Phase III study (IMM01–010) of IMM01 (Timdarpacept) in combination with azacitidine in patients with newly diagnosed CMML was approved by NMPA in May 2024.