Efficacy

Inrebic (Fedratinib) and Its Efficacy in Treating Myelofibrosis

Inrebic, which contains the active ingredient fedratinib, is a medication approved by the U.S. Food and Drug Administration (FDA) for the treatment of adults with intermediate-2 or high-risk primary or secondary (post-polycythemia vera or post-essential thrombocythemia) myelofibrosis. Clinical trials have demonstrated the efficacy of Inrebic in reducing spleen size, a common symptom of myelofibrosis, as well as improving symptoms related to the disease. The pivotal JAKARTA trial, a phase III study, showed a significant proportion of patients treated with fedratinib experienced a reduction in spleen volume of 35% or more compared to those who received a placebo.

The efficacy of Inrebic in alleviating symptoms of myelofibrosis was also assessed using the Myelofibrosis Symptom Assessment Form (MFSAF), which is a patient-reported outcome measure. Patients reported improvements in symptoms such as abdominal discomfort, pain under the left ribs, early satiety, itching, night sweats, and bone or muscle pain. These improvements were maintained over a period of 24 weeks, highlighting the potential of Inrebic to enhance the quality of life for individuals suffering from myelofibrosis.

Vonjo (Pacritinib) and Its Efficacy in Treating Myelofibrosis

Vonjo, with the active ingredient pacritinib, is another medication that has shown promise in the treatment of myelofibrosis. It is specifically indicated for the treatment of adult patients with intermediate or high-risk primary or secondary myelofibrosis who have thrombocytopenia, meaning a platelet count below 50 × 10^9/L. The efficacy of Vonjo was established through the PERSIST-1 and PERSIST-2 clinical trials. In these studies, pacritinib demonstrated a significant reduction in spleen volume when compared to best available therapy, including the JAK1/JAK2 inhibitor ruxolitinib, or a placebo in PERSIST-2.

Furthermore, the PERSIST-2 trial also showed that a higher percentage of patients treated with pacritinib achieved a 50% or greater reduction in total symptom score, which is a composite measure of myelofibrosis-related symptoms. This indicates that Vonjo not only targets the physical manifestations of myelofibrosis, such as spleen enlargement but also provides symptomatic relief. The improvement in symptoms, which include abdominal discomfort, pain under the ribs, feeling full, muscle or bone pain, night sweats, and itching, contributes to the overall benefit of pacritinib in managing myelofibrosis, particularly in patients with thrombocytopenia who have limited treatment options.