Patient Experience and Outcomes of Patients Receiving Phlebotomy for Polycythemia Vera: A Retrospective Medical Chart Audit Study
Authors: Howe Andrew , Castro Claudia , Chien Hung-Lun , De Atish , Dehipawala Sumudu , O'Hara Matthew , Geller Robert 
Published: December 2024

Introduction:

Polycythemia Vera (PV) is a rare, chronic, and life-threatening myeloproliferative neoplasm (MPN) associated with an elevated risk of thromboembolic complications, persistent symptom burden, decreased survival and a significant economic, and humanistic burden. This study aims to understand the patient journey of PV, including utilization and patient experience with phlebotomy, treatment decision-making and clinical impacts of treatments.

Methods:

A retrospective medical chart review was conducted in October-December 2023 among US hematologists/oncologists healthcare providers (HCPs) managing adult patients with a confirmed diagnosis of PV in the prior 12 months, receiving either phlebotomy alone (PLB), or any of the following cytoreductive therapies (CT) with or without concomitant phlebotomy: hydroxyurea (HU), ruxolitinib (RUX), peginterferon alfa-2a (PEG), and ropeginterferon alfa-2b-njft (ROP). Descriptive analysis were conducted to assess patient characteristics, symptom burden, NCCN recommended treatment modalities, and potential adverse effects during initial presentation of PV, diagnosis, and at the most recent HCP visit; additionally, HCP treatment rationale.

Results :

A total of 125 HCPs representing academic (30%), community (28%), and private practice (33%) settings of care abstracted data from 420 unique charts. The mean patient age was 61.5 (SD±11) years at their most recent visit, 40% of patients were male, 38% with a delayed PV diagnosis and 37% were diagnosed with low-risk status. All patients received at least one phlebotomy during the chart review. The frequency of phlebotomy (≥1 per month) within the first six months of phlebotomy initiation was 72% (n=301) which decreased to 42% (n=173) after 6 months following initiation.

As of their most recent visit, 103 patients (25%) were receiving only PLB without CT, including 56 patients identified as high risk (≥60 years or history of thrombosis). Patients receiving PLB experienced a reduction in hematocrit values from diagnosis to their most recent visit (12%) as well as significant reduction in hemoglobin (11%).

Patients on PLB experienced worsening symptom burden (33%) or symptoms not resolving (24%) from diagnosis to most recent visit with worsening pruritus, recent vision change, and ringing ears over time; severe symptoms experienced by patients included severe reddened face, gastric ulcer, anxiety/depression, and unintentional weight loss.

Among patients who discontinued on PLB (n=166), side effects were the most common reason for discontinuation across treatment strategies (63%). Side effects (44-71%) leading to discontinuation for all therapies included dizziness, headache, injection site reactions, vision changes, depression, weakness, unusual bleeding, balance impairment, skin ulcers, and gastrointestinal bleeding.

Among these patients, the top-cited reasons to consider initiation of CT would include worsening symptoms (n=34, 33%), followed by increased frequency of need for phlebotomy (n=31, 30%), symptom non-resolution (n=25, 24%), and worsening or difficult to control hematocrit (n=25, 24%). Despite the shortest duration of use (mean 8.9 months), ROP experienced the highest reduction in severe symptoms (75%) compared to RUX (45%), HU (43%) and PEG (33) respectively and a greater reduction in overall symptoms 37% vs. 25% ROP (37% vs PEG (25%)) respectively. Preferred CT to administer first for patients on PBL included HU (n=52, 50%), RUX (n=33, 32%), PEG (n=11, 11%), and ROP (n=7, 7%). Among high-risk patients, first-line CT choices were HU (n=27, 48%), RUX (n=19, 34%), PEG (n=6, 11%), and ROP (n=4, 7%).

Conclusion

PBL demonstrated efficacy in reduction/normalization of hematocrit however, patients demonstrated symptom persistence and side effects burdens. Treatment choices for initial CT after PBL, including those for high-risk patients, indicates high degree of heterogeneity and variability from NCCN clinical guidelines, which recommend initiation of ROP as a first line CT in low-risk and high-risk patients, potentially speaking to the need for additional physician education and consensus-building.

Funding:

This study is funded by PharmaEssentia.