Case 4
A 35-year-old male with CF (F508del/F508del) status post dual bilateral lung and liver transplant in late September 2018. Due to extensive sinus disease, the patient expressed interested in trialing elx/tez/iva, and as a collaborative agreement between his transplant team and CF care team, he initiated full dose elx/tez/iva therapy. Per his transplant center, labs were ordered weekly including a tacrolimus concentration, hemogram, and comprehensive metabolic panel. Baseline LFTs were WNL. At one week of therapy, the patient’s LFTs remained WNL, but his tacrolimus concentration was 25.6 ng/mL (goal: 8-10 ng/mL). That same day, he reported symptoms of tacrolimus toxicity including severe gastrointestinal upset and acute kidney injury was noted on labs with a serum creatinine of 1.6 times his baseline. His transplant center discontinued elx/tez/iva the next day when the labs resulted. No pulmonary function outcomes were measured given that he was only on modulator therapy for about one week. At this point, the patient has not been re-challenged with elx/tez/iva therapy, and does not express interest in re-challenge in the future.