Litfulo (ritlecitinib) is both a Janus kinase (JAK) inhibitor and a tyrosine kinase inhibitor. It's used to treat alopecia areata, an autoimmune condition that results in hair loss, in adults and children ages 12 years and older. Litfulo (ritlecitinib) comes as a capsule that's taken by mouth once per day. The most common side effects of this medication are headache and diarrhea.
People who have alopecia areata have a condition where their immune system attacks hair follicles by mistake, which results in hair loss.
Litfulo (ritlecitinib) is a kinase inhibitor. It works by blocking immune proteins called Janus kinase (JAK) and tyrosine kinase. In doing so, Litfulo (ritlecitinib) blocks your immune system from attacking hair follicles and causing hair loss.
The following side effects may get better over time as your body gets used to the medication. Let your healthcare provider know immediately if you continue to experience these symptoms or if they worsen over time.
Contact your healthcare provider immediately if you experience any of the following.
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
A study looked at how well Litfulo (ritlecitinib) worked for people who lost more than half of the hair on their scalp from alopecia areata. Results showed about 23% of people noticed significant hair growth within 6 months of starting Litfulo (ritlecitinib), compared to about 2% of people who took placebo. Talk with your primary care provider if you've more questions about how well Litfulo (ritlecitinib) works.
Clinical study suggests that few people might start to notice more scalp hair growth within 2 months of starting Litfulo (ritlecitinib). But you might need to take this medication for about 6 months to get a better idea if it works for you. Keep in mind that not everyone will see an improvement in hair growth after taking Litfulo (ritlecitinib). Let your prescriber know if you're concerned with how well Litfulo (ritlecitinib) is working for you.
Yes, you can still get most vaccines, including the flu shot, while taking Litfulo (ritlecitinib). But you shouldn't get live vaccines while taking or right before starting Litfulo (ritlecitinib). This is because it's not known how your body will react and if they're safe while you're taking Litfulo (ritlecitinib). Examples of live vaccines include the live flu vaccine (which is given through a nasal spray) and the MMR (measles, mumps, and rubella vaccine). Before you get any vaccines, let your primary care provider or pharmacist know that you're taking Litfulo (ritlecitinib). They can determine which vaccines are appropriate for you.
Litfulo (ritlecitinib) hasn't been studied in male pattern baldness and isn't meant for this condition. Litfulo (ritlecitinib) is only FDA-approved to treat baldness caused by alopecia areata, an autoimmune condition where your body's own immune system attacks your hair follicles. Litfulo (ritlecitinib) treats alopecia areata by stopping the immune system from attacking hair follicles. Male pattern baldness isn't an autoimmune condition; but rather, it's related to age and genetics. If you have male pattern baldness, talk with your primary care provider about possible treatment options.
Yes, Litfulo (ritlecitinib) is an oral JAK inhibitor. It's also a tyrosine kinase inhibitor. Both JAK and tyrosine kinase are immune proteins that play a role in hair loss in people with alopecia areata.
Both Litfulo (ritlecitinib) and Olumiant (baricitinib) are oral JAK inhibitors used to treat alopecia areata. One of the main differences between them is that Litfulo (ritlecitinib) is FDA-approved for children 12 years of age and older, whereas Olumiant (baricitinib) is only approved for adults. Litfulo (ritlecitinib) and Olumiant (baricitinib) haven't been directly compared to each other, so it's unclear whether one works better for alopecia areata. Talk to your healthcare team if you've questions about either medications.
Pfizer is the manufacturer that makes Litfulo (ritlecitinib).
Litfulo (ritlecitinib) 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.
Litfulo (ritlecitinib) can affect your body's ability to fight off infections. This can raise your risk of serious bacterial (e.g., tuberculosis (TB)), viral (e.g., COVID-19, hepatitis), or fungal infections. Your prescriber will routinely monitor you for infections before and during treatment with Litfulo (ritlecitinib). If you notice any signs of infection during treatment like fever, chills, body aches, or cough, let your care team know right away.
In study of a different JAK inhibitor for rheumatoid arthritis, results showed that it was linked to higher risk of death for some people, such as older adults with at least one heart-related risk factor. Talk to your prescriber about the risks and benefits of using Litfulo (ritlecitinib) before you start treatment.
In study of a different JAK inhibitor for rheumatoid arthritis, people who took the medication were at higher risk for cancer during treatment. These cancers included lymphoma and skin cancer. Some cancers have been reported by people taking Litfulo (ritlecitinib) during clinical studies. Because of this, your prescriber will monitor you for your risk of cancer during treatment. Additionally, make sure you schedule yearly screenings for skin cancer and let your healthcare team know if you notice changes to your skin. Wear protective clothing and use sunscreen if you're out in the sun, and avoid UV light (e.g., tanning beds) to lower your risk of skin cancer.
People who took JAK inhibitors reported blood clots in various parts of the body, including the heart and brain. While these conditions haven't been linked to Litfulo (ritlecitinib), these risks are still possible. Get medical help right away if you experience symptoms of blood clots, such as:
- Legs (deep vein thrombosis): leg cramp, swelling, pain, muscle tightness;
- Lungs (pulmonary embolism): cough, chest pain, trouble breathing, racing heart
- Heart (arterial thrombosis): chest pain, short of breath, pain in the jaw, neck, or back, feeling weak or light-headed
- Brain (stroke): sudden weakness in your body, trouble speaking, confusion, dizziness
- Eyes: vision changes, pain.
Although rare, Litfulo (ritlecitinib) can cause serious allergic reactions, including anaphylaxis (e.g., closing of the throat). If you experience hives, swelling in your lips, tongue, or throat, or trouble breathing, get medical help right away.
Some people who took Litfulo (ritlecitinib) saw changes in their lab tests, such as lower levels of white blood cells and platelets and higher liver enzyme levels. Because of this, your prescriber will order lab tests before and after you start Litfulo (ritlecitinib) treatment.
It's not known how Litfulo (ritlecitinib) might affect your body's response to vaccines. Before you start Litfulo (ritlecitinib) treatment, make sure you're up to date on all your vaccines. You'll need to avoid receiving live vaccines right before starting and during Litfulo (ritlecitinib) treatment.