Disease and treatment characteristics of polycythemia vera patients in Belgium: Results from a scientific survey

Real-World Clinical Characterisation of Polycythaemia Vera Patients from a Prospective Registry in Portugal: Is Resistance to Hydroxyurea a Reality?

Patients with polycythaemia vera (PV) are at increased risk of thrombosis and haemorrhages. Although hydroxyurea (HU) has been the frontline therapy for patients at high risk of vascular complications, about 25% of patients develop resistance/intolerance to this therapy. The aim of this non-interventional, multicentre cohort study was to understand the clinical characteristics and HU treatment response of Portuguese PV patients. HU resistance/intolerance was defined according to adjusted European LeukemiaNet (ELN) criteria. In total, 134 PV patients with a mean (SD) disease duration of 4.8 (5.0) years were included and followed up for 2 years. At baseline, most patients were ≥60 years old (83.2%), at high risk for thrombotic events (87.2%), and receiving HU therapy (79.1%). A total of 10 thrombotic events and 8 haemorrhagic events were reported, resulting in a 5-year probability of thrombo-haemorrhagic events of 17.2%. Haematocrit (p = 0.007), haemoglobin (p = 0.012) and MPN10 symptom score (12.0 (11.6) vs. 10.3 (9.1); p = 0.041) decreased significantly at the 24-month visit compared to baseline. Overall, 75.9% of patients met at least one of the adjusted ELN criteria for HU resistance, and 14.4% of patients remained on HU throughout the study. The results from this real-world study may help identify the subset of patients at higher risk for disease sequelae who may benefit from earlier second-line treatment.

Real-world patient characteristics and treatment patterns of polycythemia vera in Taiwan between 2016 and 2017: a nationwide cross-sectional study

Background

Polycythemia vera (PV) patients often experience constitutional symptoms and are at risk of thromboembolism as well as disease progression to myelofibrosis or acute myeloid leukemia. Not only is PV often overlooked but treatment options are also limited, however.

Objectives

To explore the patient characteristics and treatment pattern of PV patients in Taiwan, and compare with other countries reported in the literature.

Design

This is a nationwide cross-sectional study.

Methods

The National Health Insurance Research Database in Taiwan, which covers 99% of the population, was utilized. Patients were identified during the cross-sectional period between 2016 and 2017, and their retrospective data were retrieved from 2001 to 2017.

Results

A total of 2647 PV patients were identified between 1 January 2016 and 31 December 2017. This study described the demographic information of these patients, including number of patients by risk stratification and by sex, age at diagnosis, age at cross-sectional period, rate of bone marrow aspiration/biopsy at diagnosis, comorbidities, number of postdiagnosis thrombosis, number of disease progression, and death. The mortality rate of PV patients (4.1%) over 60 of age was higher than the general population of the same age group (2.8%). This study also compared the different treatment patterns between sexes and risk groups. Hydroxyurea was deferred to an older age, but conversely was prescribed at higher dose to younger patients. Alarmingly, a high proportion of patients did not receive phlebotomy or hydroxyurea for at least 2 years. Furthermore, discrepancies in prevalence, age at diagnosis, sex ratio, incidence of thrombosis and mortality were also found when compared with data reported in other countries.

Conclusion

The clinical landscape of PV in Taiwan between 2016 and 2017 was examined. Distinctive patterns of phlebotomy and hydroxyurea were identified. Overall, these findings highlight the importance of understanding the patient characteristics and treatment patterns of PV in different regions to better inform clinical practice and improve patient outcomes.

Patterns of Hydroxyurea Prescription and Use in Routine Clinical Management of Polycythemia Vera: A Multicenter Chart Review Study

Objective:

This study aimed to evaluate real-life data on patterns of hydroxyurea prescription/use in polycythemia vera (PV).

Materials and Methods:

This retrospective chart review study included PV patients who had received hydroxyurea therapy for at least 2 months after PV diagnosis. Data were collected from 10 representative academic medical centers.

Results:

Of 657 patients, 50.9% were in the high-risk group (age ≥60 years and/or history of thromboembolic event). The median duration of hydroxyurea therapy was 43.40 months for all patients; 70.2% of the patients had ongoing hydroxyurea therapy at last follow-up. Hydroxyurea was discontinued in 22.4% of the patients; the most common reason was death (38.5%). The predicted time until hydroxyurea discontinuation was 187.8 months (standard error: ±21.7) for all patients. This duration was shorter in females (140.3±37.7 vs. 187.8±29.7) (p=0.08). This trend was also observed in surviving patients aged ≥50 years at hydroxyurea initiation (122.2±12.4 vs. 187.8±30.7, p=0.03). Among the patients who were still on hydroxyurea therapy, 40.3% had a hematocrit concentration of ≥45% at their last follow-up visit, and the rate of patients with at least one elevated blood cell count was 67.8%.

Conclusion:

Hydroxyurea prescription patterns and treatment aims are frequently not in accordance with the guideline recommendations. Its discontinuation rate is higher in females.

Treatment strategies for polycythemia vera: Observations in a Dutch "real-world" cohort study

OBJECTIVES

Assessment of "real-world" treatment strategies and outcome in Dutch polycythemia vera (PV) patients.

METHODS

Retrospective chart review in 150 patients with PV (WHO 2008 diagnostic criteria) from 10 major non-academic hospitals in the Netherlands.

RESULTS

Patients (median age 64 years, 49% male) frequently had cardiovascular risk factors (56%) and prior vascular events (31%). About 70% of patients were high-risk, based on ELN criteria. However, the majority of patients were treated with phlebotomies alone (55%). Cytoreduction with hydroxyurea (HU) was received by 44% as part of their initial therapy, with or without phlebotomies. The time to achieve the 45% hematocrit target was shortest in patients treated with phlebotomies with or without HU (125 ± 99 and 197 ± 249 days, respectively) compared to patients treated with only HU (232 ± 216 days). Leukocyte and platelet levels were lower in HU-treated patients, and ELN response targets were more often reached. During the median follow-up period of 4.1 years, 14 patients (9%) suffered a thrombotic vascular event.

CONCLUSIONS

In Dutch clinical practice, there is major clinical variation in treatment strategies for PV. Phlebotomizing patients shorten the time to achieve hematocrit control, while HU better controls platelet and leukocyte levels. The thrombotic vascular event rate remains clinically significant.