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For a subset of patients with PV,

Conventional approaches to disease management may result in inadequately controlled PV

Key measures of inadequately controlled PV

Any of the following may suggest inadequately controlled PV:

Inadequately controlled PV – elevated haematocrit level, elevated leukocyte count, burdensome symptoms and intolerance to initial cytoreductive therapy – JAKAVI

Consensus guidelines help define HU resistance and intolerance

  • Guidelines published by the ELN can be used to help identify patients who have developed HU resistance and intolerance3
  • The RESPONSE trial, which assessed JAKAVI in PV, used a modified version of these guidelines to determine eligibility—these patients had inadequate response to or unacceptable side effects from HU4

Criteria for HU resistance5

Published ELN guidelines define resistance after 3 months of treatment only at a dose of ≥2 g/day of HU.3
*Or failure to completely relieve symptoms related to splenomegaly. Massive splenomegaly was defined as spleen extending >10 cm below the costal margin.5

Criteria for HU intolerance5

Criteria for hydroxyurea (HU) resistance and intolerance – JAKAVI

Or clinicohaematologic response. Complete response is defined as haematocrit <45% without phlebotomy, platelet count 400 × 109/L, WBC count 10 × 109/L, and no disease-related symptoms. Partial response is defined as haematocrit <45% without phlebotomy or response in three or more of the other criteria.

Some patients who do not meet ELN criteria for HU resistance/intolerance may still have an inadequate response or intolerance to HU or remain symptomatic6,7

Learn about JAKAVI treatment in patients with inadequately controlled PV

Next: Elevated haematocrit is associated with increased risk in PV

ELN=European LeukemiaNet; GI=gastrointestinal; RESPONSE=Randomized Study of Efficacy and Safety in Polycythemia Vera with JAK Inhibitor INCB018424 versus Best Supportive Care.


  1. Alvarez-Larrán A, Pereira A, Cervantes F, et al. Assessment and prognostic value of the European LeukemiaNet criteria for clinicohematologic response, resistance, and intolerance to hydroxyurea in polycythemia vera. Blood. 2012;119(6):1363-1369.
  2. Marchioli R, Finazzi G, Specchia G, et al. Cardiovascular events and intensity of treatment in polycythemia vera. N Engl J Med. 2013;368(1):22-33.
  3. Barbui T, Barosi G, Birgegard G, et al. Philadelphia-negative classical myeloproliferative neoplasms: critical concepts and management recommendations from European LeukemiaNet. J Clin Oncol. 2011;29(6):761-770.
  4. Vannucchi AM, Kiladjian JJ, Griesshammer M, et al. Ruxolitinib versus standard therapy for the treatment of polycythemia vera. N Engl J Med. 2015;372(5):426-435.
  5. Vannucchi AM, Kiladjian JJ, Griesshammer M, et al. Ruxolitinib versus standard therapy for the treatment of polycythemia vera [supplementary appendix]. N Engl J Med. 2015;372(5):1-25.
  6. Stein BL, Moliterno AR, Tiu RV. Polycythemia vera disease burden: contributing factors, impact on quality of life, and emerging treatment options. Ann Hematol. 2014;93(12):1965-1976.
  7. Parasuraman S, DiBonaventura M, Reith K, Concialdi K. Treatment patterns and hydroxyurea response among patients with polycythemia vera. Presented at: 56th ASH Annual Meeting and Exposition; December 6-9, 2014; San Francisco, CA.