Jakafi (ruxolitinib)
Also marketed as Jakafi XR. An approved treatment for Chronic Graft-versus-Host Disease.
The same compound appears under different names depending on the context. Here is how to identify Ruxolitinib wherever you encounter it, plus the key facts at a glance.
- Generic name
- Ruxolitinib
- Brand names
- Jakafi, Jakafi XR
- Development code
- INCB018424
- Drug class
- JAK1/JAK2 inhibitor
- Manufacturer
- Incyte Corporation
- How it's taken
- Taken as an oral tablet, either Jakafi 10 mg twice daily or the extended-release Jakafi XR 22 mg once daily (approved May 2026).
An oral JAK1/JAK2 inhibitor approved for chronic graft-versus-host disease in adults and children 12 years and older after failure of one or two prior lines of systemic therapy. The REACH-3 trial showed superior failure-free survival compared to best available therapy, making ruxolitinib the most evidence-supported novel agent for steroid-refractory cGVHD.
Where Ruxolitinib fits
The most evidence-supported second-line agent for chronic GVHD based on the REACH-3 trial's superior failure-free survival data. Often considered the first-choice novel agent after steroid failure. Part of a growing treatment landscape that now includes ibrutinib (2017), belumosudil (2021), and axatilimab (2024) for different lines of therapy.
How Ruxolitinib works
After a bone marrow or stem cell transplant, donor immune cells sometimes attack the recipient's tissues, causing chronic graft-versus-host disease. This immune attack is fueled by inflammatory signaling molecules (cytokines) that communicate through JAK1 and JAK2 proteins inside immune cells. Ruxolitinib blocks both JAK1 and JAK2, effectively turning down the volume on these inflammatory signals.
When JAK signaling is inhibited, several things happen: production of inflammatory cytokines decreases, activated immune cells calm down, and protective regulatory T cells (Tregs) expand. This rebalancing of the immune system helps reduce the attack on the patient's tissues while preserving some immune function against infections.
In the landmark REACH-3 trial, ruxolitinib produced responses in 70% of patients and delivered median failure-free survival of 38.4 months compared to just 5.7 months with best available therapy, establishing it as the standard second-line treatment for cGVHD.
Mechanism: Selective inhibitor of JAK1 and JAK2 kinases, suppressing the inflammatory cytokine signaling that drives graft-versus-host disease
Side effects and safety
The most common side effects relate to blood count changes: anemia (low red blood cells), thrombocytopenia (low platelets), and neutropenia (low white blood cells). Infections including viral reactivations (particularly cytomegalovirus) require monitoring. Other common effects include fatigue, headache, diarrhea, nausea, and muscle spasms. Blood counts are monitored regularly during treatment. The label also warns about serious infections (including tuberculosis, PML and hepatitis B flare-ups), flares of symptoms if treatment is stopped (seen mainly in myelofibrosis), non-melanoma skin cancer (regular skin checks), higher cholesterol, and, based on another JAK inhibitor, a higher risk of heart attack, stroke, blood clots, lymphoma and other cancers, especially in current or past smokers.
This is not a complete list of side effects. Talk to your doctor or pharmacist about what to expect and when to seek medical attention.
Taking Ruxolitinib
Taken as an oral tablet, either Jakafi 10 mg twice daily or the extended-release Jakafi XR 22 mg once daily (approved May 2026). Treatment continues until cGVHD progression or unacceptable side effects. No food restrictions. Dose adjustments may be needed based on blood counts or drug interactions.
Availability and cost
Only available as the brand-name product.
Help paying for Jakafi
Pick your insurance to see which help fits. Drugmaker copay cards can't be used with Medicare, Medicaid or TRICARE; charity funds are the usual route there.
- Copay help
Eligible commercially insured patients may pay as little as $0 per month for Jakafi or Jakafi XR; annual benefit maximum applies. Government-insured and uninsured patients are not eligible.
For: private insurance · source - Free medicine program
Free Jakafi for uninsured patients, Medicare Part B/D/Advantage patients, or patients whose coverage was exhausted or denied, if they meet household income criteria.
For: no insurance, underinsured, Medicare · source - Bridge or quick-start supply
Free 30-day supply if commercial or exchange-plan coverage is delayed; proof of the insurance claim and delay is required.
For: private insurance · source - Other support
If not eligible for Incyte programs, IncyteCARES can share information on independent foundations that may help with drug, travel or lodging costs.
The official page does not say who qualifies. Ask the program. · source
Good to know: Patients in Alternate Funding Programs are not eligible for free drug. Phone line Mon-Fri 8 AM-8 PM ET.
- From a charity · TotalAssist (formerly PAN Foundation)Graft-vs-Host Disease (GVHD) fundOpen
Pays for: Out-of-pocket costs for approved medications, up to $9,500 per year. Requires health insurance (any kind).
- From a charity · NMDP (formerly Be The Match / National Marrow Donor Program)NMDP Patient Financial Assistance Grants fundApply directly
Pays for: Out-of-pocket costs before and after blood or marrow transplant, ongoing GVHD treatment costs, clinical-trial travel and financial-crisis grants.
The foundation says: “Status not shown on page”
Clinical trial results
The Phase 3 REACH-3 trial randomized 329 patients with steroid-refractory or steroid-dependent cGVHD to ruxolitinib or best available therapy. Ruxolitinib achieved an overall response rate of 70% versus 57% for best available therapy. Median failure-free survival was 38.4 months versus 5.7 months (HR 0.36). The probability of sustained response at 36 months was 59.6% versus 26.7%. These results established ruxolitinib as the most effective proven option for steroid-refractory cGVHD.
Development history
Ruxolitinib was developed by Incyte Corporation and first approved for myelofibrosis in 2011, followed by polycythemia vera. The recognition that JAK signaling drives GVHD pathology led to clinical development in transplant settings. FDA approved ruxolitinib for acute GVHD in May 2019 and for chronic GVHD in September 2021 based on the REACH-3 data. It also has indications for myelofibrosis and polycythemia vera.
Explore Chronic Graft-versus-Host Disease trials
Other Chronic Graft-versus-Host Disease treatments
Common questions about Ruxolitinib
▸What is Ruxolitinib (Jakafi)?
An oral JAK1/JAK2 inhibitor approved for chronic graft-versus-host disease in adults and children 12 years and older after failure of one or two prior lines of systemic therapy. The REACH-3 trial showed superior failure-free survival compared to best available therapy, making ruxolitinib the most evidence-supported novel agent for steroid-refractory cGVHD.
▸How does Ruxolitinib work?
After a bone marrow or stem cell transplant, donor immune cells sometimes attack the recipient's tissues, causing chronic graft-versus-host disease. This immune attack is fueled by inflammatory signaling molecules (cytokines) that communicate through JAK1 and JAK2 proteins inside immune cells. Ruxolitinib blocks both JAK1 and JAK2, effectively turning down the volume on these inflammatory signals.
When JAK signaling is inhibited, several things happen: production of inflammatory cytokines decreases, activated immune cells calm down, and protective regulatory T cells (Tregs) expand. This rebalancing of the immune system helps reduce the attack on the patient's tissues while preserving some immune function against infections.
In the landmark REACH-3 trial, ruxolitinib produced responses in 70% of patients and delivered median failure-free survival of 38.4 months compared to just 5.7 months with best available therapy, establishing it as the standard second-line treatment for cGVHD.
▸What are the side effects of Ruxolitinib?
The most common side effects relate to blood count changes: anemia (low red blood cells), thrombocytopenia (low platelets), and neutropenia (low white blood cells). Infections including viral reactivations (particularly cytomegalovirus) require monitoring. Other common effects include fatigue, headache, diarrhea, nausea, and muscle spasms. Blood counts are monitored regularly during treatment. The label also warns about serious infections (including tuberculosis, PML and hepatitis B flare-ups), flares of symptoms if treatment is stopped (seen mainly in myelofibrosis), non-melanoma skin cancer (regular skin checks), higher cholesterol, and, based on another JAK inhibitor, a higher risk of heart attack, stroke, blood clots, lymphoma and other cancers, especially in current or past smokers.
▸How is Ruxolitinib taken?
Taken as an oral tablet, either Jakafi 10 mg twice daily or the extended-release Jakafi XR 22 mg once daily (approved May 2026). Treatment continues until cGVHD progression or unacceptable side effects. No food restrictions. Dose adjustments may be needed based on blood counts or drug interactions.
▸Is Ruxolitinib FDA approved?
Yes, Ruxolitinib (Jakafi) is FDA approved (2021) for the treatment of Chronic Graft-versus-Host Disease.
▸Is Jakafi approved for chronic GVHD?
Yes. Jakafi (ruxolitinib) was FDA-approved in September 2021 for chronic graft-versus-host disease in adults and children 12 years and older after failure of one or two prior lines of systemic therapy, based on the REACH-3 trial.
▸How effective is ruxolitinib for chronic GVHD?
In the REACH-3 trial, ruxolitinib achieved a 70% response rate and median failure-free survival of 38.4 months, compared to 5.7 months with best available therapy, making it the most evidence-supported option for steroid-refractory cGVHD.
Sources and references
Every factual claim on this page is drawn from the public sources listed below. Click any reference to open the original document.
- U.S. Food and Drug Administration · September 22, 2021. FDA approves ruxolitinib for chronic graft-versus-host disease. https://www.fda.gov/drugs/resources-information-approved-drugs/fda-approves-ruxolitinib-chronic-graft-versus-host-disease
- New England Journal of Medicine. Ruxolitinib vs Best Available Therapy in Steroid-Refractory Chronic GVHD. https://www.nejm.org/doi/full/10.1056/NEJMoa2033122
- Incyte Corporation. IncyteCARES for Jakafi. https://www.incytecares.com/oncology-hematology-jakafi/financial-assistance