Ritlecitinib: uses, dosing, side effects & brands

The following clinically significant adverse reactions are described elsewhere in the labeling: • Serious Infections [see Warnings and Precautions (5.1) ] • Malignancy and Lymphoproliferative Disorders [see Warnings and Precautions (5.3) ] • Thromboembolic Events [see Warnings and Precautions (5.5) ] • Hypersensitivity [see Warnings and Precautions (5.6) ] • Laboratory Abnormalities [see Warnings and Precautions (5.8) ] Most common adverse reactions (incidence ≥1%) are headache, diarrhea, acne, rash, urticaria, folliculitis, pyrexia, atopic dermatitis, dizziness, blood creatine phosphokinase increased, herpes zoster, red blood cell count decreased, and stomatitis. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact Pfizer Inc. at 1-800-438-1985 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The safety of LITFULO was evaluated in three randomized, placebo-controlled clinical trials and one long-term trial in subjects with alopecia areata, including alopecia totalis and alopecia universalis, who were 12 years of age and older. A total of 1628 subjects were treated with LITFULO…

LITFULO is contraindicated in patients with known hypersensitivity to ritlecitinib or any of its excipients [see Warnings and Precautions (5.6) ] . LITFULO is contraindicated in patients with known hypersensitivity to ritlecitinib or any of its excipients. ( 4 )

Certain CYP3A substrates : Additional monitoring and dose adjustment of CYP3A substrate should be considered. ( 7.1 ) • Certain CYP1A2 substrates : Additional monitoring and dose adjustment of CYP1A2 substrate should be considered. ( 7.1 ) • Certain CYP3A inducers: Coadministration with strong inducers of CYP3A is not recommended. ( 7.2 ) 7.1 Effects of LITFULO on Other Drugs Table 3 includes clinically significant drug interactions affecting other drugs. Table 3. Clinically Significant Interactions Affecting Other Drugs CYP3A Substrates Where Small Concentration Changes May Lead to Serious Adverse Reactions Clinical Impact Ritlecitinib is a CYP3A inhibitor. Concomitant use of ritlecitinib increases AUC and C max of CYP3A substrates [see Clinical Pharmacology (12.3 )] , which may increase the risk of adverse reactions of these substrates. Intervention Consider additional monitoring and dosage adjustment in accordance with approved product labeling of CYP3A substrates where small concentration changes may lead to serious adverse reactions when used with LITFULO. CYP1A2 Substrates Where Small Concentration Changes May Lead to Serious Adverse Reactions Clinical Impact Ritlecitinib is a CYP1A2 inhibitor. Concomitant use of ritlecitinib increases AUC and C max of CYP1A2 substrates [see Clinical Pharmacology (12.3) ] , which may increase the risk of adverse reactions of these substrates. Intervention Consider additional monitoring and dosage adjustment in accordance with the approved product labeling of CYP1A2 substrates where small concentration changes may lead to serious adverse reactions when used concomitantly with LITFULO. 7.2 Effects of Other Drugs on LITFULO Table 4 includes clinically significant drug interactions affecting LITFULO. Table 4. Clinically Significant Interactions Affecting LITFULO CYP3A Inducers Clinical Impact Concomitant use of strong CYP3A inducer (e.g., rifampin) may decrease AUC and C max of ritlecitinib [see Clinical Pharmacology (12.3) ] , which may result in loss of or reduced clinical response. Intervention Coadministration with strong inducers of CYP3A is not recommended.