Tofacitinib

Tofacitinib is a DMARD used to treat inflammatory types of arthritis, such as rheumatoid arthritis (RA).

Tofacitinib is recommended for use in combination with methotrexate (MTX) in adult patients with moderate to severely active RA who have had an inadequate response to MTX. For patients who cannot tolerate MTX, tofacitinib may be given as monotherapy.

Tofacitinib is never used in combination with biologic medications. Combining tofacitinib with biologic therapy is not recommended because of the increased risk for infection.

Tofacitinib is taken orally in pill form.

Tofacitinib is available in 5 mg tablets. The usual dose is one tablet twice daily. Your prescriber may reduce the dose if you have liver or kidney problems.

The JAK-STAT pathway is an important pathway for communication in the body related to the bone marrow and immune system activation. It involves the enzyme Janus Kinase (JAK) and a system called Transducers and Activators of Transcription (STAT). Cells in the immune system use this pathway to communicate with one another. Tofacitinib works by disrupting a key signal sending process in the JAK-STAT pathway. By doing this, tofacitinib interferes with how cells in the immune system talk with each other. This reduces the immune system’s ability to attack the joints and patients can benefit from reduced pain, swelling, and inflammation.

Like many of the DMARDs, you will not feel the effects of tofacitinib right away. Most people may start noticing the effects about two to eight weeks after they start taking the medication, but full benefits may not occur for three to six months. It is important to be patient and keep taking your medication.

Tofacitinib can make it harder for your body to fight infections. Therefore, if you have a fever or think you may have an infection, contact your health-care provider immediately. Also contact your prescriber if you are having surgery as you may need to stop tofacitinib until you are healed and there is no sign of infection.

Before taking tofacitinib, tell your health-care provider if you are pregnant or planning to become pregnant or are breastfeeding or planning to breastfeed. Women should not breastfeed while being treated with tofacitinib.

Ideally your vaccinations should be up to date prior to starting tofacitinib. If you have already started therapy with tofacitinib, most inactive vaccines are recommended, if indicated (e.g., influenza, pneumococcal). Live vaccines are not recommended due to risk of causing infection. Please speak with your health-care providers about vaccinations before starting tofacitinib.

Anyone who has had a previous allergic reaction to tofacitinib should avoid the medication.

Ask your doctor about getting the shingles vaccine, which is best administered before starting tofacitinib. 

Tofacitinib interacts with a number of other medications. Please speak with your health-care provider about whether any of the other medications you currently take interact with tofacitinib. It is also recommended that you avoid grapefruit juice and St. John’s wort while taking tofacitinib.

Your body may harbour the bacteria that can cause tuberculosis (TB) if you have been exposed to TB in the past. You may not know you are carrying TB as the bacteria remain in an inactive state and cause no symptoms. This is known as latent TB infection (LTBI). People with LTBI are not infectious and cannot spread TB to others. Tofacitinib can increase the risk of reactivation of LTBI. Prior to starting tofacitinib therapy, your prescriber will screen for LTBI. If you test positive you will be required to take an anti-TB medication prior to starting tofacitinib. Please speak with your health-care provider about LTBI screening before starting a tofacitinib.

Tofacitinib has been rarely associated with a small increased risk of developing certain types of cancer. Proof of a link between tofacitinib and the development of cancer is difficult as people with inflammatory arthritis are generally at a higher risk of developing certain cancers, as compared to the general population. The role of tofacitinib in the development of cancer is currently unknown. Please speak with your health-care provider if you have any questions.

If you are starting this medication and are a current or past smoker, or have had a heart attack, other heart problems, known malignancy or cancer, stroke, or blood clots in the past, you should ensure your doctor is aware of the risks factors you have and discuss the risks and benefits of this treatment. These factors may put you at higher risk for serious problems with this medication. It is important that your doctor is aware if you have any of these risk factors if you are starting this medication. 

If you are unsure whether your doctor is aware of these risk factors you may have, you should contact your doctor and make an appointment to discuss these risk factors as well as the risks and benefits of using this medication.

Like all medications, taking tofacitinib carries some risk of side effects, which must be balanced with the potential benefits. In general, the risk of joint damage and permanent disability (resulting from arthritis) is much greater than the risks of side effects from tofacitinib. When monitored properly the vast majority of side effects are rare, most improve over time and are reversible.

The most common side effects of tofacitinib are nausea, indigestion and diarrhea. Some people also experience headaches, high blood pressure, urinary tract infections and upper respiratory tract infections.

Tofacitinib may affect your blood counts, liver or kidney function and cholesterol levels. Your health-care provider will use blood tests to monitor for these changes.

In rare cases, tofacitinib has been associated with stomach perforations (holes in the lining of the stomach). All patients who developed stomach perforations were also taking NSAIDs and/or corticosteroids. However, the contribution of these medications to the development of stomach perforations is not known. Tofacitinib should be used with caution in patients who may be at increased risk for stomach perforation (e.g., using NSAIDs and/or corticosteroids, people with a history of diverticulitis). Stomach perforations require immediate medical attention. If you develop fever and severe stomach pain that does not go away, seek medical attention.

Recent reports have associated this medication, which belongs to a class of drugs called JAK-inhibitors, with an increased risk of serious heart-related events such as heart attack, stroke, blood clots and rarely cancer and death, particularly in those with risk factors such as having a history of smoking, past heart attack, known malignancy or cancer, stroke, or blood clots. Ensure your doctor is aware if you have any of these risk factors and discuss the risk and benefits of using this medication.

Take tofacitinib as prescribed and contact your health-care provider if you have any concerns while taking the medication.

Taking tofacitinib with food may help reduce nausea and stomach upset.

You will need blood tests every one to three months. This is important to ensure the tofacitinib is having no harmful effects on your blood counts, liver, kidneys or cholesterol levels.

Store this medication at room temperature (15 to 30 degrees Celsius) and keep it out of reach of children.

The patient support program for Xeljanz is called the “Pfizer Flex”. Their phone number is 1-855-935-3539.