Key Takeaways:
InnoCare Pharma's mesutoclax achieved a 100% overall response rate in treatment-naive myelodysplastic syndrome patients, data from the 2026 American Society of Clinical Oncology annual meeting showed.
"The results demonstrate the potential of mesutoclax as a backbone therapy for myeloid malignancies," InnoCare said in a June 2 statement.
As of April 20, among evaluable treatment-naive MDS patients, 40% achieved a complete response and 60% reached marrow CR, per IWG 2006 criteria. Using the updated IWG 2023 criteria, the composite CR rate was 90%, with a 60% CR rate. In treatment-naive acute myeloid leukemia patients, 81.8% achieved composite CR as of April 13, and 86.5% were minimal residual disease negative. Among composite CR responders, 83% reached that milestone in the first treatment cycle, indicating the regimen enables rapid remissions. In the 125-milligram mesutoclax group, the six-month duration of response rate was 93.3% and the six-month overall survival rate was 90.5%. For AML patients with TP53 mutations — a historically difficult-to-treat subgroup — the composite CR rate was 71.4% and the six-month DOR rate exceeded 50%.
No dose-limiting toxicities were observed and the maximum tolerated dose was not reached. Most non-hematologic adverse events were grade 1 or 2. Among treatment-naive AML patients, the mortality rate was 0% at both 30 and 60 days.
The data positions mesutoclax as a potential challenger to AbbVie Inc.'s venetoclax, the current standard BCL2 inhibitor for AML and related blood cancers. InnoCare, which trades on the Hong Kong and Shanghai stock exchanges under tickers 09969 and 688428, has three approved drugs and more than 10 clinical-stage candidates in its pipeline.
The 100% ORR in MDS and deep responses in AML, including TP53-mutated patients, suggest mesutoclax could address significant unmet need in myeloid malignancies where treatment options remain limited. The next catalyst for InnoCare will be any update on a regulatory submission pathway for mesutoclax.
This article is for informational purposes only and does not constitute investment advice.
