Among patients with phlebotomy-dependent polycythemia vera (PV), treatment with rusfertide, a hepcidin mimetic administered weekly as a subcutaneous injection, continues to be effective, results in sustained hematocrit control, and eliminates the need for repeated phlebotomies. These results from the ongoing phase II REVIVE trial were presented at the 2022 American Society of Clinical Oncology (ASCO) Annual Meeting. Patients received rusfertide for 28 weeks, after which they could continue therapy in the open-label extension phase for up to 36 months after a 12-week withdrawal phase. Of 70 patients, 84% did not require a phlebotomy, 14% required one, and 2% required two during the initial 28 weeks of rusfertide treatment. The therapy was equally effective in controlling hematocrit levels in patients who were treated previously with phlebotomy alone or those who required myelosuppressive agents. Patients had been treated for up to 1.5 years and essentially did not need phlebotomies. Patients had normalized iron stores, as measured by ferritin levels, and reduced red blood cell counts, yet therapy did not affect white blood cell or platelet counts. Most adverse events (AEs) were grade 1 or 2. Injection site reactions were the most common, occurring with 33% of injections. There were no grade 3 AEs related to rusfertide. One grade 4 event occurred in a patient with asymptomatic thrombocytosis possibly related to rusfertide. Two patients withdrew from the trial as a result of AEs possibly related to the therapy. “Rusfertide can potentially be used to treat virtually all patients with PV,” Dr. Hoffman said. “This drug will likely allow one to reduce the doses of myelosuppressive agents and eliminate the need for supplemental phlebotomy in order to maintain [normal] hematocrit levels associated with a reduced risk of thrombotic events.” A phase III clinical trial in patients with PV (VERIFY) has been developed to validate these phase II results.
Jakafi (ruxolitinib) was approved by FDA in 2022 as a second line therapy for PV when patients did not respond adequately or resistant or intolerant to hydroxyurea.
One spoken error: At 30 sec, I said "a tight bonding between oxygen (O2) and hemoglobin". It should be "a tight bonding between carbon monoxide (CO) and hemoglobin". Because CO molecule binds to hemoglobin very tightly, O2 molecules gradually lose their place in RBCs. Its like when a naughty girl (CO) steals a man's heart and attaches to him (Hemoglobin) too tightly, a good girl (O2) has no chance to associate with the man (hemoglobin) and the good girl (O2) loses her chance to let him know her. So, the carboxyhemoglobin (COHb) occupying the RBC has no O2 to give to the tissue of the organ resulting in low tissue O2 concentration. Patients with secondary polycythemia from chronic carbon monoxide poisoning have normal O2 saturation when measured with a pulse oxymetry device because it falsely overestimates the SPO2 in the presence of high COHb. Therefore, when you suspect carbon monoxide poisoning, you need to get the arterial blood gas (ABG) analysis in order to obtain the accurate SPO2.
I was diagnosed with hyperthyroidism with secondary polycythemia. I already had 2 therapeutic phlebotgomies. I’m currently taking methimazole for my hypertyhroidism. Will my hgb/hct go back to normal once my thyroid hormones are corrected? Thank you very much.
I am not sure if hydroxyurea is a very toxic drug. I have old patients whose age older than 80 have been taking more than 20 years without problem and children with sickle cell anemia takes it daily for many years.
I have high platelets with JAK2 V617F. Platelets average around 450,000. RBCs run on average about 5.1, Hemoglobin averages around 15.6 to 16.0 and Hematocrit around 46 to 49. I have been diagnosed with ET via BMB but wonder if my condition is not PV instead? My CBCs have been pretty stable for decades.
You probably have thalassemia trait, either alpha or beta. Then you do not have polycythemia. Patients with thalassemia trait have a small size RBC shown as a low MCV. Please watch my RU-vid lecture about thalassemia.
@@chetanrs in my report normal range is from 14-16 . Initially it was 16.6 after 9 days it was 16.5. and after 1 week during donating blood drop to 16. I hve no PVC and Rbc count in the report. WBC count=6700
