Valemetostat

Valemetostat (CAS No. 1809336-39-7) is a first-in-class selective EZH1/2 inhibitor, with histone methyltransferase EZH2 (wild-type and Y641, A677, A687 mutant variants) as its core therapeutic target. It exhibits an IC₅₀ of approximately 1.5 nM against wild-type EZH2 and 0.3~0.5 nM against mutant EZH2, while displaying weak inhibitory activity against EZH1 (IC₅₀ > 10 μM), thus possessing high specificity. Clinically, it is indicated for the treatment of relapsed/refractory follicular lymphoma, with a recommended oral dosage of 80 mg twice daily. The objective response rate (ORR) can reach 73.3%, and the therapeutic efficacy is more pronounced in patients harboring EZH2 mutations. Additionally, it has demonstrated potential activity in diffuse large B-cell lymphoma, without causing significant severe toxicities such as myelosuppression.

References:

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