According to recent research published in Blood, treatments with therapeutic phlebotomy and hydroxyurea improved overall survival and decreased thrombosis risk in patients with polycythemia vera.
Additionally, the researchers found that despite proven efficacy and guideline recommendations, therapeutic phlebotomy and hydroxyurea are underused in this patient population.
“Current guidelines recommend therapeutic phlebotomy for all polycythemia vera patients and additional cytoreductive therapy (eg, hydroxyurea [HU]) for high-risk PV patients,” Nikolai A Podoltsev, MD, PhD, of the hematology division at Yale University School of Medicine, and colleagues wrote. “However, both treatment modalities were underused in this population of… older patients, as only 64% underwent therapeutic phlebotomy, and 60.6% received hydroxyurea.”
Doctor and patient discussing therapies. Source: Getty
The researchers retrospectively studied a cohort of 820 older patients with polycythemia vera, diagnosed between 2007 and 2013. They utilized multivariable cox proportional hazards models to determine the impact of the two study treatments on overall survival in the patient cohort.
Study results showed that mortality was significantly reduced in patients who received phlebotomy and a higher proportion of days covered by hydroxyurea. Additionally, increasing phlebotomy intensity was also associated with lower mortality (P < .01).
Despite these efficacy results, the researchers found that a significant proportion of the study cohort were not treated with therapeutic phlebotomy and hydroxyurea, per ELN and NCCN guidelines.
The researchers posit that this disconnect between real world practice and guideline recommendations could also result in less use of cytoreductive treatment.
“Same guidelines recommend second-line cytoreductive treatment of patients who are refractory to or intolerant of hydroxyurea, including ruxolitinib, interferons, and busulfan,” Podoltsev and colleagues wrote. “The fact that very few patients received these medications in our study further illustrates the underutilization of cytoreductive treatments. Ruxolitinib was approved by the US Food and Drug Administration as a second-line treatment of PV patients refractory to or intolerant of hydroxyurea in December 2014…”
The researchers concluded that “improved dissemination and implementation of the guidelines may translate to better patient outcomes.”