Patients who receive immunosuppressants as a result of organ or hematopoietic stem-cell transplantation are more susceptible to COVID-19 infection and may not benefit from current COVID-19 vaccines. Lena Peter, Berlin Institute of Health Center for Regenerative Therapies, Berlin, Germany, describes treating COVID-19 in immunocompromised patients with adoptive T-cell therapy. T-cells derived from donors were isolated and were made resistant to tacrolimus, a common immunosuppressant, via knockout of the gene encoding FKBP12. In vivo studies determined the modified T-cells to effectively target COVID-19 and its variants, and Phase 1 are currently being planned to assess the novel approach. This interview took place at the International Conference on Lymphocyte Engineering (ICLE) 2022.