SEL24/MEN1703 is being Evaluated for the Treatment of Acute Myeloid Leukemia (AML)

Poster Accepted for Presentation at the 62^nd American Society of Hematology (ASH) Annual Meeting

Pomezia, Italy, December 1^st, 2020 – Menarini Ricerche, the R&D division of the Menarini Group, reported today the positive results of the pharmacodynamic assay demonstrating target engagement in the dose escalation part of the DIAMOND-01 trial (CLI24-001; clinicaltrials.gov identifier NCT03008187), a study investigating SEL24/MEN1703, a first-in-class, orally available, dual PIM/FLT3 inhibitor as single agent in Acute Myeloid Leukemia (AML).

The poster entitled “SEL24/MEN1703 provides PIM/FLT3 Downstream Pathway Inhibition in Acute Myeloid Leukemia (AML) Blast Cells: Results of the Pharmacodynamic (PD) Assay in the Dose Escalation Part of First-in-Human DIAMOND Trial” will be presented at the 62^nd American Society of Hematology (ASH) Annual Meeting and Exposition, which will take place virtually on December 5-8.

“We are pleased with the preliminary, positive results observed with SEL24/MEN1703, a PIM/FLT3 inhibitor under investigation for the treatment of AML. As outlined in our ASH poster presentation, the dose escalation phase of the DIAMOND-01 trial showed that SEL24/MEN1703 has a manageable safety profile and results in a meaningful target engagement in peripheral blood and bone marrow blast cells from patients treated with SEL24/MEN1703,” said Andrea Pellacani, General Manager of Menarini Ricerche. “We look forward to continuing our investigation of SEL24/MEN1703 as a potential new treatment for this aggressive and hard-to-treat cancer, as part of our commitment to develop effective innovative therapies that can make a difference in the lives of cancer patients.”

DIAMOND-01 is the First-in-Human, Phase I/II dose escalation and cohort expansion trial of SEL24/MEN1703, in-licensed by Menarini from Ryvu Therapeutics, in AML. The study has completed the dose escalation part showing a manageable safety profile up to the recommended dose of 125 mg/day, with initial evidence of anti-leukemic activity in a single agent setting.

The objective of the pharmacodynamic assessment was to investigate the degree of target engagement achieved at different doses of SEL24/MEN1703, by measuring the phosphorylation of S6 (pS6), a downstream effector of the PIM/FLT3 signaling pathway. In addition, the correlation between pS6 levels and the anti-leukemic effect of SEL24/MEN1703 was assessed in samples collected from patients enrolled in the dose escalation part of the DIAMOND-01 trial. The quantitative assessment of pS6 at a single-cell level was performed both on peripheral blood (PB) and bone marrow (BM) blast cells samples.

The results of this assay confirmed that meaningful target engagement was achieved, both in PB and BM blast cells, in patients treated with SEL24/MEN1703 at 100 mg/day (one dose level below the recommended dose) and at 125 mg/day. Moreover, preliminary data suggest that the PIM/FLT3 pathway inhibition might be associated with blast count reduction, particularly in those patients showing high phosphorylation of S6 at baseline.

We will continue to measure target engagement with this assay in the cohort expansion part of the DIAMOND-01 trial, which is currently recruiting patients with relapsed or refractory AML in both the EU and the US.