Subcutaneous Mirikizumab Found Tolerable After Hypersensitivity Reaction to IV Infusion
A case study published in The American Journal of Gastroenterology presented at Advances in Inflammatory Bowel Diseases (AIBD), highlights a successful rechallenge with subcutaneous (SC) mirikizumab following a hypersensitivity reaction to intravenous (IV) infusions in a patient with ulcerative colitis (UC) and primary sclerosing cholangitis (PSC). This finding underscores the potential for continued use of mirikizumab in patients experiencing mild infusion-related reactions.
The patient, a 24-year-old woman with a history of UC and PSC diagnosed in 2016, had previously failed multiple therapies, including infliximab, adalimumab, vedolizumab, ustekinumab, tofacitinib, and upadacitinib. After declining surgery, mirikizumab was initiated. She received 300 mg IV infusions at weeks 0, 4, and 8, followed by SC injections of 200 mg every 4 weeks starting at week 12.
After the first infusion, the patient developed generalized pruritus and hives, which resolved with diphenhydramine. Subsequent infusions with premedications (diphenhydramine and dexamethasone) resulted in mild reactions that resolved with antihistamines. Following consultation with an allergist, the patient transitioned to SC mirikizumab with premedication using cetirizine. She has since tolerated 3 maintenance SC injections without adverse reactions.
Clinical improvements included reduced urgency and more formed stools, accompanied by a decrease in fecal calprotectin levels from 224 mcg/g to 109 mcg/g over 4 months.
This case suggests that SC mirikizumab may remain a viable option after mild infusion-related hypersensitivity reactions, with proper premedication and careful monitoring. Further studies may help establish protocols for rechallenging biologic therapies in similar scenarios.
Reference
Crosby S, Squire J, Hashash JG. Rechallenge with subcutaneous mirikizumab after mild hypersensitivity reaction to intravenous mirikizumab in a patient with ulcerative colitis and primary sclerosing cholangitis. Presented at: Advances in Inflammatory Bowel Disease annual meeting; December 9-11, 2024. Orlando, Florida.
