Who is INREBIC for?
INREBIC is a prescription medicine used to treat adults with primary or secondary intermediate-2 or high-risk myelofibrosis (MF).
That includes patients:
- Who have been previously treated with ruxolitinib
- Who have not taken a JAK inhibitor
- With platelet counts over 50 x 109/L)
How was INREBIC clinically studied?
The clinical trial of INREBIC was called JAKARTA. The JAKARTA study looked at whether INREBIC was safe and effective in treating adult patients with intermediate-2 or high-risk primary or secondary MF with splenomegaly.
The study included 289 patients who had intermediate-2 or high-risk primary or secondary myelofibrosis. INREBIC users were compared with a group given a placebo. In the study, 97 patients took a 500-mg dose, 96 patients took a 400-mg dose and 96 patients took a placebo. The recommended daily dose is 400 mg, so only data from the group of patients that took the 400-mg dose are shown.
The study was designed to look at:
- The main study goal, or primary endpoint of the study, was to measure the number of patients who had a 35% reduction or more in the volume of their spleen. This was measured after patients took 6 cycles of INREBIC and then had follow-up scans 4 weeks later.
- To measure the change in spleen volume, patients had an MRI or CT scan after Cycle 3 and Cycle 6.
- Also in this clinical trial, an additional goal, or secondary endpoint, of the study was to measure the percent of people who had a 50% or greater reduction in their Total Symptom Score (TSS) after 6 cycles of taking INREBIC. The TSS tallied symptom scores for each patient and looked at the following symptoms:
Bone or muscle pain
Pain under ribs on left side
In the JAKARTA trial, symptoms were measured by the modified Myelofibrosis Symptom Assessment Form (MFSAF) v2.0 diary.
The modified MFSAF v2.0 is a patient diary that looked at 6 core symptoms of MF: night sweats, itching, abdominal discomfort, early satiety, pain under ribs on left side, and bone or muscle pain. The modified MFSAF diary was filled out daily during the week prior to Day 1 of each treatment cycle, and at the end of Cycle 6. Symptom scores ranged from 0 (“absent”) to 10 (“worst imaginable”). These scores were added to create the Total Symptom Score (TSS).
What did the INREBIC study show?
Reduced spleen volume
In the JAKARTA study, 37% of patients had greater than or equal to 35% reduction in spleen volume after taking INREBIC for 6 cycles, with a follow-up scan 4 weeks later.
*Out of the 289 patients, 97 patients received 500-mg dose, 96 patients 400-mg dose,
and 96 patients a placebo. The recommended daily dose is 400 mg. That is why the
500-mg dose arm of the study is not shown in the chart.
MF symptoms studied
INREBIC showed reduction in MF symptoms as measured by the Total Symptom Score (TSS) calculation at the end of Cycle 6.
*A total of 89 patients receiving INREBIC 400 mg and 81 patients receiving placebo were evaluated in the study for this endpoint.
†Some symptoms had significant reduction but that does not mean that they went away.
Selected safety findings
Most Common Side Effects (reported in > 20% of Patients Taking INREBIC)
These are not all of the possible side effects of INREBIC.
INREBIC may cause serious side effects, such as: Encephalopathy (including Wernicke’s encephalopathy). A serious and sometimes fatal neurological problem called encephalopathy (including Wernicke’s encephalopathy) has happened in some people who take INREBIC. Wernicke’s encephalopathy is a neurologic emergency that can happen if you do not have enough vitamin B1 (thiamine) in your body. Your healthcare provider will do a blood test to check your vitamin B1 level before starting and during treatment with INREBIC. Your healthcare provider may tell you to stop taking INREBIC and take a vitamin.