Industry eyes myelofibrosis drug Ojjaara’s reimb progress

in Korea

GSK Korea prepares to submit reimbursement listing application in December

Can be prescribed regardless of JAK inhibitor treatment history

Interest is gathering on the insurance reimbursement of Omjjara, a targeted therapy for myelofibrosis.

 

According to industry sources, GSK Korea is preparing to submit a reimbursement application for its myelofibrosis drug, Ojjaara (momelotinib) in Korea.

 

The company is expected to submit its application next month (December).  Specifically, the indication the company will apply for reimbursement is for the “treatment of myelofibrosis in intermediate- or high-risk adults with anemia.” The drug’s approved indication includes both primary myelofibrosis and myelofibrosis post-polycythemia vera (PV) and post-essential thrombocythemia (ET).

 

Unlike existing drugs that act on a single target, Ojjaara is a multi-target drug that blocks all three major signaling pathways that lead to the disease, providing a potent treatment effect.

 

The drug blocks three key signaling pathways, including the JAK1 and JAK2 proteins that were inhibited by existing therapies, and the ACVR1 (activin A receptor type).

 

The recommended dose is 200 mg orally once daily and can be taken with or without food.

 

Myelofibrosis is a rare blood cancer in which the bone marrow becomes fibrotic, causing symptoms such as anemia, thrombocytopenia, and spleen and liver enlargement.

 

It affects about 1 in 100,000 people worldwide, and in Korea, about 2,292 patients were confirmed to have received inpatient and outpatient treatment for the condition as of 2023.

 

Patients with anemia symptoms in particular have a poor prognosis, and the problem is that the majority of patients experience anemia.

 

In one study, 87% of patients with myelofibrosis were anemic at the time of referral, and in another study, 46% of patients required a blood transfusion more than a year after diagnosis.

 

In general, the development of anemia in myelofibrosis patients doubles the risk of death compared to other prognostic factors such as age, leukocytosis, and systemic symptoms.

 

In 2 global Phase III clinical trials - the SIMPLIFY-1 study and the MOMENTUM study - Ojjaara confirmed the clinical efficacy and safety profile of anemia in adult myelofibrosis patients, including the treatment of key symptoms such as improved splenomegaly and reduced transfusion dependency in patients with anemia.  The SIMPLIFY-1 study directly compared Ojjaara to ruxolitinib in 432 adult myelofibrosis patients who had not previously received JAK inhibitor therapy, with a post hoc analysis in the anemia subgroup.  The results demonstrated non-inferiority of Ojjaara to ruxolitinib for the primary efficacy endpoint of spleen volume response (>35% reduction) at 24 weeks of treatment but did not show non-inferiority in terms of total symptom score improvement.

 

The proportion of patients in each arm who were transfusion-free was 66.5% in the Ojjaara arm and 49.3% in the ruxolitinib arm, with significantly lower transfusion dependence (better transfusion independence) in the Ojjaara arm.

 

In the MOMENTUM study, another pivotal trial, which evaluated the efficacy and safety of Ojjaara versus danazol in 195 adult patients with myelofibrosis who were previously treated with a JAK inhibitor and had symptoms and anemia.  All subjects enrolled in the study had previously received ruxolitinib, and 4.6% had received fedratinib.

 

The co-primary efficacy endpoints were the proportion of patients with a 50% or greater reduction in Total Symptom Score (TSS) at 24 weeks of treatment and transfusion independence.

 

Key secondary endpoints included spleen volume response.