Efficacy and safety of JAK inhibitor INC424 in patients with primary and post-polycythemia vera or post-essential thrombocythemia myelofibrosis in the Chinese population

Abstract

A phase II study (A2202) was performed to evaluate the efficacy and safety of JAK inhibitor ruxolitinib in 63 Chinese MF patients. Ruxolitinib was given twice a day (bid) at a starting dose of 15 mg (n=25) or 20 mg (n=38) based on a baseline platelet count. About 94.7% of the patients achieved a reduction in spleen size, 27.0% of which exhibited significant reduction (≥35%) at week 24. Significant improvement in debilitating constitutional symptoms, as assessed by MFSAF v2.0, was observed in patients treated with ruxolitinib. Ruxolitinib treatment was generally well tolerated by Chinese patients. Although the treatment was associated with an increase in certain adverse events (AEs) that were established as identified risks (anemia and thrombocytopenia), these AEs were considered manageable in this clinical setting. Ruxolitinib provided substantial reductions in splenomegaly and improvements in symptoms, and was well-tolerated by Chinese patients with MF.

Keywords

JAK / ruxolitinib / Chinese patients / myelofibrosis

References

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Acknowledgements

This project was supported by Novartis China.

Xin Du and Daobin Zhou declare that they have no conflict of interests. All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and the Helsinki Declaration of 1975 as revised in 2000 (5). Informed consent was obtained from all patients for being included in the study. Ethical approval was provided by the Medical Ethics Committee of Guangdong General Hospital and Peking Union Medical College Hospital.

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2016 Higher Education Press and Springer-Verlag Berlin Heidelberg