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.