Abstract
Ruxolitinib is a potent Janus kinase (JAK) 1/JAK2 inhibitor that has demonstrated rapid and durable improvements in splenomegaly and symptoms and a survival benefit in 2 phase 3 trials in patients with myelofibrosis. Ruxolitinib was well tolerated and effectively reduced splenomegaly and symptom burden in Asian patients with myelofibrosis in the Asian multinational, phase 2 Study A2202. We present a subset analysis of Japanese patients (n = 30) in Study A2202. At data cutoff, 22 patients were ongoing; 8 discontinued, mainly due to adverse events (n = 4). At week 24, 33 % of patients achieved ≥35 % reduction from baseline in spleen volume; 56.0 % achieved ≥50 % reduction from baseline in total symptom score, as measured by the 7-day Myelofibrosis Symptom Assessment Form v2.0. The most common adverse events were anemia (63 %), thrombocytopenia (40 %), nasopharyngitis (37 %), decreased platelet counts (30 %), and diarrhea (30 %). Dose reductions or interruptions due to hemoglobin decreases were more frequent in Japanese patients; no loss of efficacy and no discontinuations due to hematologic abnormalities were observed. Ruxolitinib was well tolerated in Japanese patients and provided substantial reductions in splenomegaly and myelofibrosis-related symptoms similar to those observed in the overall Asian population and phase 3 COMFORT studies.
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Acknowledgments
We would like to thank Professor Mineo Kurokawa for his contributions as a study investigator (University of Tokyo Hospital, Tokyo, Japan). Editorial assistance was provided by Karen Chinchilla, PhD, and was supported by Novartis.
Conflict of interest
K. Oritani has received grants-in-aid for scientific research and collaborated with Fujifilm; S. Okamoto has received research funding from Novartis; T. Tauchi, S. Saito, K. Ohishi, H. Handa, K. Takenaka, and K. Akashi have nothing to disclose; P. Gopalakrishna is an employee of Novartis Pharma AG; T. Amagasaki and K. Ito are employees of Novartis Pharma KK.
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Oritani, K., Okamoto, S., Tauchi, T. et al. A multinational, open-label, phase 2 study of ruxolitinib in Asian patients with myelofibrosis: Japanese subset analysis. Int J Hematol 101, 295–304 (2015). https://doi.org/10.1007/s12185-015-1746-8
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DOI: https://doi.org/10.1007/s12185-015-1746-8