Vonjo (pacritinib) is a type of targeted therapy called a JAK inhibitor. It’s used to treat adults with a rare blood cancer called myelofibrosis (MF). This medication specifically helps people with MF who have very low platelet counts. Vonjo (pacritinib) is a capsule that you take by mouth twice a day. The medication might cause side effects like diarrhea, nausea, and swelling. It might also raise the risk of easy bleeding or bruising.
Intermediate or high-risk primary or secondary myelofibrosis (MF) in adults with a platelet count below 50,000/µL
Vonjo (pacritinib) is a type of targeted therapy known as JAK inhibitor. This means it blocks JAK2 proteins. JAK2 proteins usually send signals that tell blood cells to grow and divide. The medication can also block the protein IRAK1, which does something similar.
People with MF have abnormal JAK2 proteins that work out of control. By blocking these abnormal JAK2 proteins, Vonjo (pacritinib) helps stop abnormal blood cells from growing too much in people with MF.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
A pill that’s taken by mouth
Can take with or without food
Recommended treatment option for adults with myelofibrosis and low platelets
Taken twice a day
Might cause side effects like bleeding and diarrhea
Might not be safe to take with certain medications because of drug interactions
Take Vonjo (pacritinib) twice a day, with or without food. Set up reminders on your phone to help you remember when to take the medication. Taking it around the same times each day can also help make it a part of your daily routine.
Swallow Vonjo (pacritinib) capsules whole. Don’t chew, open, or break them.
Tell your prescriber if you have any surgeries, procedures, or dental work planned. Also let your other care teams know you’re taking Vonjo (pacritinib). This medication can raise your risk of bleeding, so you might need to stop taking it a few days before. Only start taking it again when your prescriber says it’s safe. Always follow your care team’s instructions.
It’s common to have diarrhea while taking Vonjo (pacritinib). Be sure to drink plenty of fluids so you don’t get dehydrated if you have a lot of diarrhea. Your oncologist or hematologist might tell you to have medications for diarrhea, like loperamide (Imodium A-D), on hand. If diarrhea doesn’t get better with medication, call your healthcare team.
Vonjo (pacritinib) can sometimes cause nausea or vomiting. If your stomach feels upset, try eating smaller, more frequent meals during the day. You can ask your oncologist or hematologist about getting antiemetic medications to help with these side effects.
If you miss a dose of Vonjo (pacritinib), skip it and wait to take the medication at the next usual time and dose. Don’t take extra capsules to make up for a missed dose.
Ask your oncology team about the best way to handle and throw away Vonjo (pacritinib) safely. Anticancer medications can be harmful to people who handle or come in contact with them. Keep Vonjo (pacritinib) up and away, so children, pets, and others can’t reach it.
If you want to have children in the future, talk to your oncologist or hematologist about ways to preserve fertility. Vonjo (pacritinib) might affect fertility in males.
Vonjo (pacritinib) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Some people taking Vonjo (pacritinib) can have bleeding. Sometimes, it can sometimes be serious and, in rare cases, even life-threatening. Serious bleeding can happen in people with low platelets (below 50,000/µL).
Your care team will check your platelet levels with blood tests while you’re taking Vonjo (pacritinib). If your levels are too low, your prescriber might tell you stop the medication for a while or take a lower dose. This helps lower the risk of bleeding.
Tell your oncology or hematology team if you have any surgeries, medical procedures, or dental work planned. Because of the risk of bleeding, your prescriber will probably tell you to stop taking Vonjo (pacritinib) 7 days before the procedure to keep you safe. Follow their instructions on when you can start taking it again.
Call your care team right away if you have any unusual bleeding or bruising while taking Vonjo (pacritinib). Watch for things like unexplained bruising, nosebleeds that won’t stop, bloody urine, or blood in your stool.
Diarrhea is a common side effect of Vonjo (pacritinib). In studies, people had diarrhea generally within the first 2 months of treatment. It got better over a couple weeks to a few months. Sometimes, diarrhea can even be serious.
If you have diarrhea while taking Vonjo (pacritinib), make sure to stay hydrated. Drink plenty of fluids like water or Pedialyte. Avoid sugary sports drinks such as Gatorade, as these can make diarrhea worse.
Also tell your care team if you have watery stools or more stools than usual while taking Vonjo (pacritinib). It’s important to treat diarrhea right when it begins. Your prescriber can help decide the best way to treat it. They might lower your dose of Vonjo (pacritinib) or suggest medications to help with the diarrhea.
Most people with myelofibrosis have platelet levels that are lower than normal (also called thrombocytopenia). But it’s possible for Vonjo (pacritinib) to make the platelet count drop even more. Platelets help clot blood. So when they’re low, this puts you at risk of bleeding.
Your clinical care team will check your platelet counts often with lab tests. If your platelets get too low, you might need to take a break from Vonjo (pacritinib) to help. Your prescriber might then lower your dose when you can restart the medication.
Risk factors: Long QT syndrome | Low potassium levels | Taking other medications that can cause long QT syndrome
Vonjo (pacritinib) can make the heart take longer to recharge between beats. This is called QT prolongation. It can sometimes cause dangerous changes to heart rhythm, though this hasn’t been reported with Vonjo (pacritinib) so far.
To help keep you safe, your oncologist or hematologist will check your heart rhythm while you’re taking Vonjo (pacritinib). You’ll need to get tests called electrocardiograms (EKGs) to do this. If your heart rhythm isn’t normal, you might need to take a break from Vonjo (pacritinib) for a while.
Your care team will also check your potassium levels during treatment. Having low potassium can put you at greater risk of heart rhythm problems. If your potassium is low, you might need to take a potassium pill or get potassium as an infusion through the vein.
Risk factors: At risk of heart disease | Currently smoke | Have smoked in the past
Talk to your oncology or hematology team about your risk of serious health problems like heart attack or stroke while taking Vonjo (pacritinib). Make sure to tell them about all your medical conditions and if you’ve ever smoked. This helps them check your risk.
This warning comes from experiences of people with RA who took a medication like Vonjo (pacritinib). They had a higher risk of heart attack or stroke than those who took a different kind of medication called TNF blockers. These events could be life-threatening. Vonjo (pacritinib) isn’t approved for RA. But it works in a similar way as that other medication so it could have the same risk.
Get medical help right away if you have signs of a heart attack, like sudden chest pain, trouble breathing, sweating, or nausea.
Also call for medical help if you have signs of a stroke. These can include numbness on one side of the body, a drooping face, severe headache, or trouble speaking or walking.
It’s possible that there could be a risk of blood clots with Vonjo (pacritinib). People with RA who took a similar medication to Vonjo (pacritinib) have had blood clots. This includes deep vein thrombosis (DVT) and pulmonary embolism (PE). Although Vonjo (pacritinib) isn’t approved for RA, it works the same way as that medication.
To be safe, watch for signs of a blood clot. They include swelling in one arm or one leg, sudden chest pain, and sudden trouble breathing. Get medical help right away if this happens while taking Vonjo (pacritinib).
Risk factors: Known cancer (besides non-melanoma skin cancer) | Currently smoke | Have smoked in the past
Talk to your oncology or hematology care team about the risk of getting a new cancer while taking Vonjo (pacritinib). They can review the risks and benefits of treatment.
This risk is based on findings that people with RA who took a similar medication had a higher chance of getting new cancers, like lymphoma, than those who took TNF blockers. Vonjo (pacritinib) isn’t approved for RA. But it’s still important to know about this risk to stay safe.
It’s possible for Vonjo (pacritinib) to raise your risk of serious infection. This includes bacterial, viral, and fungal infections.
Before you start taking Vonjo (pacritinib), tell your oncology care team about any health problems you have. If you have an infection, you should wait until it goes away before starting the medication.
Call your oncologist or hematologist right away if you think you might have an infection. Signs to watch for include a fever (a temperature over 100.4ºF), body aches, chills, tiredness, trouble breathing, or a cough.
Tell your care teams about the medications you take or plan to take. Vonjo (pacritinib) can interact with other medications and can sometimes be harmful. Your care team and pharmacist can check your medication list for interactions to make sure everything is safe to take together. Remember to update them if your medications change.
You can’t take Vonjo (pacritinib) if you take certain medications known as CYP3A4 inhibitors and CYP3A4 inducers. Inhibitors can make the levels of Vonjo (pacritinib) too high in your body. This can raise the risk of serious side effects. Examples of strong inhibitors include antibiotics like clarithromycin, heart medications like diltiazem (Cardizem), and antifungals like itraconazole (Sporanox). Inducers, like carbamazepine (Tegretol), can make the levels of Vonjo (pacritinib) in your body too low. This might make it not work well to treat MF.
In addition, some medications can raise your risk of heart rhythm problems like Vonjo (pacritinib) can. These medications include ciprofloxacin, antipsychotics like aripiprazole (Abilify), and some antidepressants, among others. Taking these medication with Vonjo (pacritinib) can make your risk of heart rhythm problems even higher.
The typical dose is 200 mg by mouth twice a day.
Your oncologist can lower the dose if you have serious side effects.
Take medications known as strong CYP3A4 inhibitors or CYP3A4 inducers
Intermediate or high-risk primary or secondary myelofibrosis (MF) in adults with a platelet count below 50,000/µL
Intermediate or high-risk myelofibrosis (MF) in adults
Polycythemia vera (PV) in adults who can’t take or have already tried hydroxyurea (Hydrea)
Acute graft-versus-host disease (aGVHD) in people 12 years and older who’ve already tried corticosteroids
Chronic graft-versus-host disease (cGVHD) in people 12 years and older who’ve already tried at least one therapy option already
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