| Manufacturer || Pfizer
| Disease || Rheumatoid Arthritis
| Indication || Moderately to severely active rheumatoid arthritis
| Mode of Action || Inhibitor of Janus kinases (JAKs)
| Approval Status || EMA approved (EU); FDA approved (USA); TGA approved (AUS)
| Strength || 5 mg
Who is tofacitinib for?
Xeljanz (tofacitinib) is indicated for the treatment of patients with moderately to severely active rheumatoid arthritis who have had an inadequate response or intolerance to methotrexate. It may be used as monotherapy or in combination with methotrexate 
or other nonbiologic disease-modifying antirheumatic drugs 
Complete information about Xeljanz (tofacitinib) dosage and administration can be found here: 
The standard dosage is:
Consult your treating doctor for personalised dosing.
What is tofacitinib and how does it work?
Xeljanz (tofacitinib) is an inhibitor of Janus kinases (JAKs) used to treat adult patients with moderately to severely active rheumatoid arthritis who have had an inadequate response or intolerance to methotrexate 
The active substance in Xeljanz, tofacitinib, works by blocking the action of enzymes known as Janus kinases which play an important role in the process of inflammation and joint damage that occurs in rheumatoid arthritis. By blocking their action, tofacitinib helps reduce the inflammation and other symptoms of the disease 
What is tofacitinib's approval status?
Xeljanz (tofacitinib) was approved by, among others:
- FDA (USA) on November 6, 2012 
- EMA (EU) on March 22, 2017 
- TGA (AUS) on February 5, 2015 
for the treatment of adults with moderately to severely active rheumatoid arthritis who have had an inadequate response or intolerance to methotrexate.
The approvals were based on 6 studies in over 4,200 patients with rheumatoid arthritis which have shown the effectiveness of tofacitinib at reducing joint pain and swelling, improving joint movement and slowing down joint damage 
. An important measure in patients with rheumatoid arthritis is the ACR 20, 50 or 70 which is a criteria to measure the improvement of patients of 20 %, 50 % or 70 % based on measures as swollen joint count, tender joint count, patient assessment of global status, acute phase reactant (dramatic increase in hepatic synthesis of plasma proteins which accompanies acute phases of tissue injury and inflammation), health professional assessment of global status, physical function, and pain 
In the clinical studies patients treated with either 5 or 10 mg Xeljanz (tofacitinib) twice daily had ACR20, ACR50, and ACR70 response rates over two times higher than placebo. Higher ACR20 response rates were observed within 2 weeks compared to placebo and were consistent at 6 and 12 months 
. Detailed information about the clinical studies can be found here: 
The most commonly reported adverse reactions were upper respiratory tract infections, headache, diarrhea, and nasopharyngitis