Ruxolitinib use in myelofibrosis patients: the single center experience and the relationship between JAK-2 allele burden and Ruxolitinib response

Abstract

Purpose: Ruxolitinib is an oral JAK-1/2 inhibitor approved for the treatment of splenomegaly and/or constitutional symptoms in intermediate and high-risk myelofibrosis patients. The aim of our study is to evaluate the efficacy and safety of ruxolitinib in primary MF, post-ET MF and post-PV MF patients, to evaluate the relationship between response and JAK-2 mutation rate and to compare them with literature data. Materials and Methods: In our single centered and retrospective study, we investigated the data of 30 MF patients diagnosed in our clinic between May 2015 and December 2019. We reported demographic features, laboratory values, and spleen sizes. Results: 18 patients (60%) with a median age of 67.5 (45-78) had primary myelofibrosis. Spleen sizes decreased significantly 3 and 6 months after treatment. Constitutional symptoms have disappeared in 28 patients (93.3%). No association was found between JAK-2 mutation rate and treatment response success. Conclusion: Ruxolitinib MF is very safe and effective to relieve constitutional symptoms and decrease spleen size. Despite JAK-2 inhibition, no linear relationship was found between JAK-2 mutation rate and treatment efficacy.

Keywords

• Ruxolitinib
• Efficacy
• JAK2 mutation
• Myelofibrosis
• Response rate

Myelofibrozis hastalarında Ruxolitinib kullanımı: tek merkez deneyimi ve JAK-2 allel yükü ile Ruxolitinib yanıtı arasındaki ilişki

Abstract

Abstract: Purpose: Ruxolitinib is an oral JAK-1/2 inhibitor approved for the treatment of splenomegaly and/or constitutional symptoms in intermediate and high-risk myelofibrosis patients. The aim of our study is to evaluate the efficacy and safety of ruxolitinib in primary MF, post-ET MF and post-PV MF patients, to evaluate the relationship between response and JAK-2 mutation rate and to compare them with literature data. Materials and Methods: In our single centered and retrospective study, we investigated the data of 30 MF patients diagnosed in our clinic between May 2015 and December 2019. We reported demographic features, laboratory values, and spleen sizes. Results: 18 patients (60%) with a median age of 67.5 (45-78) had primary myelofibrosis. Spleen sizes decreased significantly 3 and 6 months after treatment. Constitutional symptoms have disappeared in 28 patients (93.3%). No association was found between JAK-2 mutation rate and treatment response success. Conclusion: Ruxolitinib MF is very safe and effective to relieve constitutional symptoms and decrease spleen size. Despite JAK-2 inhibition, no linear relationship was found between JAK-2 mutation rate and treatment efficacy.

Keywords

• ruksolitinib
• etkinlik
• jak2 mutasyonu
• myelofibrozis
• yanıt oranı

References

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