Product Description

Description:

Tofacitinib is a Janus kinase (JAK) inhibitor that works inside cells by blocking enzymes involved in immune and inflammatory responses. Normally, JAK enzymes transmit signals from cytokines and growth factors, activating STAT proteins that regulate gene expression and immune function. Tofacitinib inhibits this pathway by preventing STAT activation, thereby reducing inflammation and immune activity. It acts on multiple JAK combinations (JAK1/JAK2, JAK1/JAK3, JAK2/JAK2), although the exact contribution of each pathway to its clinical effects is not fully established.

Indications:

Tofacitinib (including extended-release forms) is indicated for:

Rheumatoid arthritis in adults with moderate to severe disease who have not responded adequately to methotrexate (used alone or with nonbiologic DMARDs)

Psoriatic arthritis in adults with inadequate response to methotrexate or other DMARDs

Ankylosing spondylitis in adults who did not respond well to one or more TNF blockers

Moderate to severe ulcerative colitis in adults

Polyarticular course juvenile idiopathic arthritis (pcJIA) in patients aged 2 years and older who have not responded to TNF blockers

Limitation: It should not be used together with biologic DMARDs or strong immunosuppressants such as azathioprine or cyclosporine.

Dosage and Administration:

Treatment should not be started if lymphocyte count is <500 cells/mm³, neutrophil count <1000 cells/mm³, or hemoglobin <9 g/dL.

Rheumatoid Arthritis & Ankylosing Spondylitis: 5 mg twice daily or XR 11 mg once daily

Psoriatic Arthritis: 5 mg twice daily or XR 11 mg once daily (with nonbiologic DMARDs)

Ulcerative Colitis:

Induction: 10 mg twice daily or XR 22 mg once daily for 8 weeks (up to 16 weeks if needed)

Maintenance: 5 mg twice daily or XR 11 mg once daily

Higher doses may be used short-term if response is lost, with careful risk assessment

Juvenile Idiopathic Arthritis: 5 mg twice daily or weight-based equivalent

Dose adjustment is required in moderate to severe renal impairment or moderate hepatic impairment. Always use the lowest effective dose.

Side Effects:

Common adverse effects include upper respiratory tract infections, nasopharyngitis, diarrhea and headache. In ulcerative colitis, additional effects may include increased cholesterol, rash, elevated creatine phosphokinase and herpes zoster. Higher doses may increase the risk of blood clots and death.

Precautions:

Avoid use during active serious infections

Use cautiously in patients at risk of gastrointestinal perforation

Regular laboratory monitoring is required (blood counts, liver enzymes, lipids)

Avoid live vaccines during treatment

Pregnancy and Lactation:

Tofacitinib is classified as Pregnancy Category C. It should be used during pregnancy only if clearly necessary. It is not known whether it passes into breast milk; therefore, a decision should be made to discontinue either breastfeeding or the drug based on clinical need. Extra caution is advised in elderly patients due to increased risk of infections.

Drug Interactions:

Strong CYP3A4 inhibitors (e.g., ketoconazole): dose adjustment required

Moderate CYP3A4 inhibitors with CYP2C19 inhibitors (e.g., fluconazole): dose adjustment required

Strong CYP3A4 inducers (e.g., rifampin): not recommended

Immunosuppressants (e.g., azathioprine, tacrolimus, cyclosporine): not recommended

Storage:

Store below 30°C, protect from light, and keep out of reach of children.

⚠️ Always use this medication under the supervision of a registered healthcare professional.