BackgroundIn May 2022, a multi-national mpox outbreak was reported in several non-endemic countries. The only licensed treatment for mpox in the European Union is the orally available small molecule tecovirimat, which inOrthopoxviruses inhibits the function of a major envelope protein required for the production of extracellular virus.MethodsWe identified presumably all patients with mpox that were treated with tecovirimat in Germany between the onset of the outbreak in May 2022 and March 2023 and obtained demographic and clinical characteristics by standardized case report forms.ResultsA total of twelve patients with mpox were treated with tecovirimat in Germany in the study period. All but one patient identified as men who have sex with men (MSM) who were most likely infected with mpox virus (MPXV) through sexual contact. Eight of them were people living with HIV (PLWH), one of whom was newly diagnosed with HIV at the time of mpox, and four had CD4+ counts below 200/µl. Criteria for treatment with tecovirimat included severe immunosuppression, severe generalized and/or protracted symptoms, a high or increasing number of lesions, and the type and location of lesions (e.g., facial or oral soft tissue involvement, imminent epiglottitis, or tonsillar swelling). Patients were treated with tecovirimat for between six and 28 days. Therapy was generally well-tolerated, and all patients showed clinical resolution.ConclusionsIn this cohort of twelve patients with severe mpox, treatment with tecovirimat was well tolerated and all individuals showed clinical improvement.