Ruxolitinib (Topical)

Ruxolitinib cream is a (JAK) inhibitor indicated for

• The topical short-term and non-continuous chronic treatment of mild to moderate atopic dermatitis in non-immunocompromised adult and pediatric patients 12 years of age and older.
• The topical treatment of nonsegmental vitiligo in adult and pediatric patients 12 years of age and older.

Janus kinase (JAK) pathways inhibitor; JAK consists of a group of intracellular tyrosine kinases that transmit signals from cytokine or growth factor-receptor interactions on the cellular membrane to influence cellular processes of hematopoiesis and immune cell function, including inflammation associated with atopic dermatitis. JAKs phosphorylate and recruit signal transducers and activators of transcription (STATs) which modulate intracellular activity including gene expression. JAK inhibitors modulate the JAK signaling pathway, which in turn prevents the phosphorylation and activation of STATs.

• Absorption: Peak plasma concentration: 449 nM (adults); 110 nM (adolescents). AUC: 3,215 h.nM (adults); 801 h.nM (adolescents).
• Distribution: Protein bound of Ruxolitinib is approximately 97%.
• Metabolism: Primarily metabolized by CYP3A4 and CYP2C9 (lesser extent) in vitro. Half-life: 116 hr.
• Excretion: Urine (74%) and feces (22%); <1% excreted as unchanged drug.

For atopic dermatitis: Apply a thin layer of Ruxolitinib twice daily to affected areas of up to 20% body surface area. Stop using when signs and symptoms (e.g., itch, rash, and redness) of atopic dermatitis resolve.

For nonsegmental vitiligo: Apply a thin layer of Ruxolitinib twice daily to affected areas of up to 10% body surface area.

• Drug interaction studies were not conducted
• Ruxolitinib is a substrate of CYP3A4
• Strong CYP3A4 inhibitors
• Avoid coadministration
• Strong CYP3A4 inhibitors may increase ruxolitinib systemic exposure and adverse reactions

It is contraindicated in patients with known hypersensitivity to the drug or any of its components.

Side effects of Ruxolitinib cream are Nasopharyngitis (3%), Bronchitis (1%), Ear infection (1%), Eosinophil count increased (1%), Urticaria (1%), Diarrhea (1%), Folliculitis (1%), Tonsillitis (1%), Rhinorrhea (1%).

Serious infections: i) Serious and sometimes fatal infections due to bacterial, mycobacterial, invasive fungal, viral, or other opportunistic pathogens reported with oral JAK inhibitors, ii) Serious lower respiratory tract infections reported in the clinical development program with topical Ruxolitinib.

Viral reactivation: Viral reactivation, including cases of herpes virus reactivation (eg, herpes zoster), were reported with JAK inhibitors used to treat inflammatory conditions.

Hepatitis B and C: i) Impact of JAK inhibitors used to treat inflammatory conditions on chronic viral hepatitis reactivation is unknown, ii) Patients with history of hepatitis B or C infection were excluded from clinical trials.

Pyrrolopyrimidines

Store below 30°C away from sunlight and keep out of reach of children.