Ruxolitinib for Polycythemia Vera in Patients Resistant to or Intolerant of Hydroxyurea.

Ruxolitinib for the Treatment of Polycythemia Vera in Patients Who Are Resistant to or Intolerant of Hydroxyurea: a Retrospective Non-interventional Study Using the US Optum Electronic Health Record Data Source.

This was an analytical and descriptive, non-interventional, retrospective cohort study of PV patients aged ≥ 18 years in the US using a secondary data source, Optum EHR database.

The Optum EHR database was current up to 30-Jun-2020.

Identification period: From 01-Apr-2007 to 30-Jun-2019

Study period: From 01-Jan-2007 to 30-Jun-2020

Index date:

First evidence of resistance to or intolerance of HU treatment in patients with PV according to modified European Leukemia Net (ELN) criteria and defined as:

1. HCT ≥ 45% with phlebotomy (last phlebotomy within last 3 months) Or
2. Platelet count > 400 x 109/L and presence of palpable splenomegaly (palpable spleen up to 3 months after platelet count)

Pre-index period:

Patients had a minimum of 3 months pre-index data available. Pre-index data availability was determined using the reported 'first month active' field.

Post-index period:

There was no minimum post-index period required. Each patient had a 'first month active' and 'last month active' reported within the database. As the 'last month active' was based on any activity in the database, including encounters such as letters and emails which occurred several months after the 'death_date' of the patient, using the 'last month active' can overestimate the follow-up for a given patient. For this reason, the end of follow-up for each patient was defined as the date of the last activity within the diagnosis, observations, prescriptions, laboratories, procedures tables or discharge date from the last visit within the visit table (whichever of these activities occurs latest). This underestimated the follow-up for some patients where they were not actively using healthcare resources.

Inclusion Criteria:

Included patients:

• With at least one International Classification of Diseases, 9th Revision, Clinical Modification/International Classification of Diseases,10th Revision, Clinical Modification code for PV in the identification period (01-Apr-2007 until 30-Jun-2019) that had non-missing sex and year of birth data and who were treated as part of the Integrated Delivery Network
• That were ≥ 18 years old at PV diagnosis
• With ≥ 2 prescriptions of HU
• That were classified as resistant to or intolerant of HU after a minimum of 3 months HU treatment (index date), defined as:

HCT ≥ 45% with phlebotomy (last phlebotomy within last 3 months) or Platelet count > 400 x 109/L and presence of palpable splenomegaly (palpable spleen up to 3 months after platelet count).

To identify patients in the RUX group:

- With ≥ 2 prescriptions of RUX in the post-index period.

Exclusion Criteria:

Excluded patients:

- With a MF or AML diagnosis prior to a PV diagnosis.