Phlebotomy Burden Undermines Consistent PV Control

Treatment burden is high for polycythemia vera (PV), one of the most common myeloproliferative neoplasms, with patients frequently encountering access, logistical, and adherence issues when undergoing phlebotomy. Experts are calling for approaches to this standard, typical first-line treatment for PV^1,2 that are safer, more effective, and better tolerated to lend consistency to patient outcomes in a variety of care settings.^3,4 This need for improvements to the phlebotomy process for PV, an incurable condition, was evident in a pair of abstracts presented at the 2026 American Society of Clinical Oncology Annual Meeting.

Both abstracts stressed the importance of the goal for patients with PV to achieve and maintain a total red blood cell count below 45% of total blood volume,⁵ as measured via hematocrit (HCT).

Treatment Approaches Need to Be More Sustainable³

HCT is greatly dependent on phlebotomy. However, new evidence from the Adelphi PV Disease Specific Programme, a cross-sectional survey that took place from August 2025 to January 2026, shows phlebotomy may be inadequate for this goal, with repeated procedures deemed a logistical challenge.

Investigators performed a retrospective chart review using Adelphi data, gleaning information on patient demographics, disease characteristics, and treatment history. They defined frequent phlebotomy as 3 or more procedures in the past 6 months or 5 or more procedures in the past 12 months and uncontrolled HCT at any measure at or above 45% in the past year. A total of 143 patients were included, with a median (IQR) age of 65 years (52-70) and a median time since diagnosis of 11 months (4.0-33.5), most of whom were male (77%), had undergone at least 1 phlebotomy in the prior year (60%), and were considered high risk (62%) due to older age or thrombosis history.

Top treatment barriers were care coordination challenges (22%), lack of resources (12%), travel time (12%), and vein access (10%). Fifty percent of the patients experienced at least 1 phlebotomy-related challenge. This translated to 38% of patients considered not fully adherent to their recommended treatment plan and 76% of patients undergoing the procedure on an infrequent basis. Overall, 90% of patients had uncontrolled HCT. Since their PV diagnosis, 13% had experienced a thromboembolism, and of those patients, 45% had experienced one in the 12 months prior to the survey.

“These findings highlight the need for more effective and sustainable approaches to prevent consequences, such as TEs,” the authors concluded, “commonly associated with uncontrolled HCT, while also reducing pt burden.”

Treatment Approaches Need to Be More Effective and Tolerable⁴

The second abstract’s authors explained that they wanted a more thorough understanding of phlebotomy patterns overall, as the procedure’s use can vary, with potential adverse impacts on utilization from treatment interruptions, discontinuation, and iron deficiency. They used a retrospective chart review on adult patients diagnosed with PV between August 2020 and July 2023 and who had at least 2 years of follow-up unless deceased (N = 128). Median patient age was 62 years, with most patients (n = 60) treated in the community setting over a mean follow-up of 2.7 years.

For this analysis, poor phlebotomy response was defined as the patient not meeting hematologic criteria, demonstrating intolerance to phlebotomy, and not benefiting from the procedure. Overall, 45% of medical centers planned to administer phlebotomy every 4 weeks, making this the most common frequency, with 79% of treatment plans aiming for HCT below 45%, and community centers besting academic centers by 10 percentage points (86% vs 76%). However, the mean phlebotomy rate was 7.3 per patient per year, and more were performed by academic centers (8.1 vs 7.5).

First phlebotomy interruptions were most often due to a hematologic reason (56%). Among those who discontinued treatment, the most common reasons were hematologic (41%), patient-centered factors (18%), and limited tolerability (18%). The mean treatment duration was longer at academic medical centers vs community centers (296 vs 262 days) before patients ultimately discontinued the procedure. After discontinuation, half of patients went on to cytoreductive treatment (hydroxyurea or ruxolitinib, 19% each; ropeginterferon alfa‑2b, 12%); the other half stayed off treatment. Iron deficiency was seen in 17% of patients overall, with slightly more community-treated vs academic center–treated patients experiencing this outcome (14% vs 13%). Of these patients, 93% also experienced fatigue and 60% paused phlebotomy.

“These findings highlight a need for more effective, better-tolerated treatments that reduce PHL reliance, achieve and maintain HCT control and support consistent care across settings,” the authors concluded.

References

1. Treatment for myeloproliferative neoplasms (MPN). Memorial Sloan Kettering Cancer Center. Accessed June 10, 2026. https://www.mskcc.org/cancer-care/types/leukemias/treatment/treatment-myeloproliferative-neoplasms
2. Bukszpan D. Polycythemia vera and phlebotomy. myMPNteam. Updated February 9, 2021. Accessed June 10, 2026. https://www.mympnteam.com/resources/polycythemia-vera-and-phlebotomy
3. Pettit KM, Fan A, Hammond C, et al. Phlebotomy, adherence, and hematocrit control in patients with polycythemia vera in the United States: real-world analysis. Presented at: American Society of Clinical Oncology Annual Meeting; May 29-June 2, 2026; Chicago IL. Abstract 6568.
4. Pemmaraju N, Fan A, Cerretani A, et al. Real-world phlebotomy (PHL) burden and treatment gaps in US patients with polycythemia vera: a chart review across physician practice settings. Presented at: American Society of Clinical Oncology Annual Meeting; May 29-June 2, 2026; Chicago IL. Abstract e18588.
5. Hematocrit test. Cleveland Clinic. Updated May 12, 2025. Accessed June 10, 2026. https://my.clevelandclinic.org/health/diagnostics/17683-hematocrit