Efficacy and Safety of Pegylated Interferon Alfa in Polycythemia Vera
Condition: Polycythemia Vera
MeSH terms: Polycythemia Vera; Polycythemia
Study type: Interventional
Phase: Phase 2

Summary: 
      Interferon alfa is an effective treatment of polycythemia vera (PV), but about 20% of
      patients discontinue their treatment because of side effects and treatment schedule (three
      times per week administration). The pegylated form of interferon alfa-2a has shown a better
      tolerance in hepatitis patients and is administered only once a week. The purpose of this
      study is to determine efficacy and safety of pegylated interferon alfa-2a in the treatment of
      PV patients.
    

Detailed description: 
      The aim of PV treatment is to reduce the risk of vascular thrombosis without enhancing the
      long-term risk of evolution toward myelofibrosis or MDS/AL. Although currently controversial,
      phlebotomies have been shown in the old PVSG01 study to increase the risk of both thrombosis
      and myelofibrosis. On the other hand, currently available cytoreductive treatments have been
      shown to efficiently reduce the thrombotic risk, but were demonstrated (32P, busulfan,
      chlorambucil) or suspected (pipobroman, hydroxyurea) to enhance the risk of evolution to
      MDS/AL. In fact, the main widely used cytoreductive treatment, when indicated, is hydroxyurea
      (HU). This drug is very efficient to control myeloproliferation with a response rate of 80 to
      90%. It is generally well tolerated, even if long term toxicity leads to treatment change in
      10% of cases. Although no prospective study has yet clearly demonstrated its leukemogenic
      potential in PV, a non-leukemogenic alternative treatment is highly warranted, especially for
      younger patient.

      Interferon (IFN) alpha is a promising agent in PV both because of good efficacy and absence
      of leukemogenic risk. Expanded experience with IFN-alpha was recently reported, showing a
      control of erythrocytosis in approximately 75% of patients. A similar percentage of patients
      also have resolution of disease-related symptoms, in particular a reduction in spleen size
      and relief from intractable pruritus. In some cases, long-term persisting remissions after
      treatment discontinuation have been observed as well as demonstration of eradication of the
      myeloproliferative clone. However, 20% of patients may not tolerate the treatment because of
      side effects. Furthermore, the treatment schedule (three times per week administration) may
      be a factor reducing long-term compliance to this drug.

      In this regard, pegylated-IFN could be a major drug in PV. The weekly administration and
      better tolerance by comparison to IFN reported in hepatitis patients could allow to obtain
      results similar to chemotherapy in terms of compliance to treatment and efficacy, with a
      major advantage, its lack of mutagenicity.
    

Intervention name(s): pegylated interferon-alfa 2a
Intervention type(s): Drug
Intervention MeSH terms: Interferons; Interferon-alpha; Interferon alpha-2; Peginterferon alfa-2a
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: myeloproliferative disorder; polycythemia vera; interferon