Incyte Release: Phase 3 RESPONSE-2 Study of Jakafi (ruxolitinib) Meets Primary Endpoint

WILMINGTON, Del.--(BUSINESS WIRE)--Incyte Corporation (Nasdaq:INCY) announces the Phase 3 RESPONSE-2 study of Jakafi® (ruxolitinib) met its primary endpoint. Treatment with Jakafi achieved hematocrit control without the need for phlebotomy in patients with inadequately controlled polycythemia vera (PV) resistant to or intolerant of hydroxyurea (HU) who did not have an enlarged spleen, compared to best available therapy (BAT). The safety profile of ruxolitinib was consistent with previous studies.

“What Are the Signs and Symptoms of Polycythemia Vera?”

"The results from the RESPONSE-2 study demonstrate the clinical benefits of treatment with Jakafi in PV patients without enlarged spleens,” said Rich Levy, MD, Chief Drug Development Officer, Incyte. “We look forward to further analysis of the safety and efficacy data and to sharing the results with the scientific community and regulatory authorities in the coming months.”


RESPONSE-2 is a multi-center, open label, randomized, Phase 3 study evaluating the efficacy and safety of ruxolitinib versus BAT. The trial randomized 149 patients with PV who are resistant to or intolerant of HU, dependent on phlebotomy for hematocrit control and do not have an enlarged spleen. Patients were randomized 1:1, by stratification (based on HU-resistance or intolerance) to receive either ruxolitinib (10 mg twice-daily) or BAT, which was defined as investigator selected monotherapy or observation only. The dose was adjusted as needed throughout the study.

About Polycythemia Vera

Polycythemia vera (PV) is a myeloproliferative neoplasm (MPN) and is typically characterized by elevated hematocrit, the volume percentage of red blood cells in whole blood, which can lead to a thickening of the blood and an increased risk of blood clots, as well as an elevated white blood cell and platelet count1. Patients with PV who fail to consistently maintain appropriate blood count levels, including appropriate hematocrit levels, have an approximately four times higher risk of major thrombosis (blood clots) or cardiovascular death2. Patients with PV can also suffer from an enlarged spleen and a significant symptom burden which may be attributed to thickening of the blood and lack of oxygen to parts of the body3. These symptoms commonly include fatigue, itching, night sweats, bone pain, fever, and weight loss4.

Approximately 100,000 patients in the U.S. are living with PV5. Current standard treatment for PV is phlebotomy (the removal of blood from the body) plus aspirin. When phlebotomy can no longer control PV, chemotherapy such as hydroxyurea, or interferon, is utilized6,7. Approximately one in four patients with PV are considered uncontrolled8,9 because they have an inadequate response to or are intolerant of hydroxyurea, the most commonly used chemotherapeutic agent for the treatment of PV.

About Jakafi (ruxolitinib)

Jakafi is a first-in-class JAK1/JAK2 inhibitor approved by the U.S. Food and Drug Administration, for treatment of people with polycythemia vera (PV) who have had an inadequate response to or are intolerant of hydroxyurea.

Jakafi is also indicated for treatment of people with intermediate or high-risk myelofibrosis (MF), including primary MF, post–polycythemia vera MF, and post–essential thrombocythemia MF.

Jakafi is marketed by Incyte in the United States and by Novartis as Jakavi® (ruxolitinib) outside the United States.

Important Safety Information

Jakafi can cause serious side effects, including:

Low blood counts: Jakafi may cause your platelet, red blood cell, or white blood cell counts to be lowered. If you develop bleeding, stop taking Jakafi and call your healthcare provider. Your healthcare provider will perform blood tests to check your blood counts before you start Jakafi and regularly during your treatment. Your healthcare provider may change your dose of Jakafi or stop your treatment based on the results of your blood tests. Tell your healthcare provider right away if you experience unusual bleeding, bruising, fatigue, shortness of breath, or a fever.

Infection: You may be at risk for developing a serious infection during treatment with Jakafi. Tell your healthcare provider if you develop any of the following symptoms of infection: chills, nausea, vomiting, aches, weakness, fever, painful skin rash or blisters.

Skin cancers: Some people who take Jakafi have developed certain types of non-melanoma skin cancers. Tell your healthcare provider if you develop any new or changing skin lesions.

The most common side effects of Jakafi include: anemia, low platelet count, bruising, dizziness, headache.

These are not all the possible side effects of Jakafi. Ask your pharmacist or healthcare provider for more information. Tell your healthcare provider about any side effect that bothers you or that does not go away.

Before taking Jakafi, tell your healthcare provider about all the medications, vitamins, and herbal supplements you are taking and all your medical conditions, including if you have an infection, have or had tuberculosis (TB), or have been in close contact with someone who has TB, have or had liver or kidney problems, are on dialysis, had skin cancer or have any other medical condition. Take Jakafi exactly as your healthcare provider tells you. Do not change or stop taking Jakafi without first talking to your healthcare provider. Do not drink grapefruit juice while on Jakafi.

Women should not take Jakafi while pregnant or planning to become pregnant, or if breast-feeding.

Full Prescribing Information, including a more complete discussion of the risks associated with Jakafi, is available at

About Incyte

Incyte Corporation is a Wilmington, Delaware-based biopharmaceutical company focused on the discovery, development and commercialization of proprietary therapeutics, primarily for oncology. For additional information on Incyte, please visit the Company’s website at

Forward Looking Statements

Except for the historical information set forth herein, the matters set forth in this press release, including statements regarding the long-term efficacy and safety of Jakafi and the disclosure of such data, contain predictions, estimates and other forward-looking statements. These forward-looking statements are based on the Company’s current expectations and subject to risks and uncertainties that may cause actual results to differ materially, including unanticipated developments and the risks related to the efficacy or safety of the Company’s development pipeline, the results of further research and development, the high degree of risk and uncertainty associated with drug development, clinical trials and regulatory approval processes, other market or economic factors and competitive and technological advances; and other risks detailed from time to time in the Company’s reports filed with the Securities and Exchange Commission, including its Form 10-Q for the quarter ended September 30, 2015. Incyte disclaims any intent or obligation to update these forward-looking statements.


Leukemia & Lymphoma Society. “Polycythemia Vera Facts.” Available at: Accessed November 2015.


Marchioli R, Finazzi G, Specchia G, et al. Cardiovascular Events and Intensity of Treatment in Polycythemia Vera. N Engl J Med. 2013;368:22-33.


National Institutes of Health. “What Are the Signs and Symptoms of Polycythemia Vera?" Available at: Accessed November 2015.

4 Tefferi A. Polycythemia Vera and Essential Thrombocythemia: 2013 Update on Diagnosis, Risk-Stratification, and Management. Am J Hematol. 2013;88:507-16.
5 Data on file. Incyte Corporation
6 Vannucchi AM. How I treat polycythemia vera. Blood. 2014; 124(22):3212-20
7 Passamonti F. How I treat polycythemia vera. Blood. 2012; 120(2):275-84.
8 Barosi G, Birgegard G, Finazzi G, et al. A Unified Definition of Clinical resistance and Intolerance to Hydroxycarbamide in Polycythaemia Vera and Primary Myelofibrosis: Results of a European LeukemiaNet (ELN) consensus process. Br J Haematol. 2010;149:961-3.
9 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;119:1363-9

For Incyte Corporation
Catalina Loveman, +1-302-498-6171
Michael Booth, DPhil, +1-302-498-5914

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