Introduction:
Mogamulizumab, anti-CC chemokine receptor type 4 (CCR4) antibody, has been used for treatment of adult T cell leukemia (ATL). It depletes Treg cells as well as ATL cells, and the recurrence of autoimmune disease was reported as an adverse effect of mogamulizumab. The association between mogamulizumab therapy and exacerbation of systemic lupus erythematosus (SLE) has not been reported so far.
Methods:
Case Description: We report a woman in her 70s who had been treated for lupus nephritis and presented ATL due to HTLV-1 infection. She was referred to Department of Hematology and started mogamulizumab therapy. After 2nd course of mogamulizumab, she presented renal insufficiency, thrombocytopenia, and anemia with schistocytes. ADAMTS13 activity was normal (0.58 IU/ml). She showed hypocomplementemia which suggested exacerbations of lupus nephritis and was diagnosed with secondary thrombotic microangiopathy. Plasma exchange (PE) with prednisolone administration was introduced following methylprednisolone pulse therapy. After 8 courses of PE, schistocytes disappeared. Although renal insufficiency improved, bicytopenia and hypocomplementemia persisted. Bone marrow biopsy revealed hypocellular bone marrow, then we stopped PE and she was treated with eltrombopag and red blood cell transfusion. Hypocomplementemia gradually improved with oral prednisolone monotherapy afterward.
Results:
Discussion: Our case suggests the association between mogamulizumab and SLE exacerbation. Based on the previous reports of autoimmune response after mogamulizumab therapy, the drug effect in Treg depletion may lead to the exacerbation of lupus nephritis with thrombotic microangiopathy. In our case, schistocytes disappeared with PE but the therapeutic effect was limited. On this point, a previous report showed PE decreased the plasma concentration of mogamulizumab but PE did not lead to the quick recovery of Treg cells.
Conclusions:
Further investigation about the pathological effect of mogamulizumab therapy on disease activity in SLE and effective treatment for disease exacerbation should be needed.
I have no potential conflict of interest to disclose.
I did not use generative AI and AI-assisted technologies in the writing process.