A phase II study of vorinostat (MK-0683) in patients with polycythaemia vera and essential thrombocythaemia.

Abstract

Inhibition of histone deacetylases may be an important target in patients with myeloproliferative neoplasms. This investigator-initiated, non-randomized, open-label phase II multi-centre study included 63 patients (19 essential thrombocythaemia, 44 polycythaemia vera) from 15 centres. The primary objective was to evaluate if vorinostat was followed by a decline in clonal myeloproliferation as defined by European Leukaemia Net. Thirty patients (48%) completed the intervention period (24 weeks of therapy). An intention-to-treat response rate of 35% was identified. Pruritus was resolved [19% to 0% (P = 0·06)] and the prevalence of splenomegaly was lowered from 50% to 27% (P = 0·03). Sixty-five per cent of the patients experienced a decrease in JAK2 V617F allele burden (P = 0·006). Thirty-three patients (52% of patients) discontinued study drug before end of intervention due to adverse events (28 patients) or lack of response (5 patients). In conclusion, vorinostat showed effectiveness by normalizing elevated leucocyte and platelet counts, resolving pruritus and significantly reducing splenomegaly. However, vorinostat was associated with significant side effects resulting in a high discontinuation rate. A lower dose of vorinostat in combination with conventional and/or novel targeted therapies may be warranted in future studies.

• Authors: Christen L Andersen, Mary F McMullin, Elisabeth Ejerblad, Sonja Zweegman, Claire Harrison, Savio Fernandes, David Bareford, Steven Knapper, Jan Samuelsson, Eva Löfvenberg, Olle Linder, Bjørn Andreasson, Erik Ahlstrand, Morten K Jensen, Ole W Bjerrum, Hanne Vestergaard, Herdis Larsen, Tobias W Klausen, Torben Mourits-Andersen, Hans C Hasselbalch
• Journal: British journal of haematology (Br J Haematol) Vol. 162 Issue 4 Pg. 498-508 (Aug 2013) ISSN: 1365-2141 [Electronic] England
• PMID: 23758082 (Publication Type: Clinical Trial, Phase II, Journal Article, Multicenter Study, Research Support, Non-U.S. Gov't)
• Copyright: © 2013 John Wiley & Sons Ltd.

Chemical References

• Biomarkers
• Histone Deacetylase Inhibitors
• Hydroxamic Acids
• Vorinostat
• JAK2 protein, human
• Janus Kinase 2

Topics

• Adult
• Aged
• Aged, 80 and over
• Biomarkers
• Fatigue (chemically induced)
• Female
• Gastrointestinal Diseases (chemically induced)
• Hematologic Diseases (chemically induced)
• Histone Deacetylase Inhibitors (adverse effects, therapeutic use)
• Humans
• Hydroxamic Acids (adverse effects, therapeutic use)
• Janus Kinase 2 (genetics)
• Male
• Middle Aged
• Mutation, Missense
• Patient Dropouts
• Polycythemia Vera (drug therapy, genetics)
• Thrombocythemia, Essential (drug therapy, genetics)
• Treatment Outcome
• Vorinostat