Eligible participants will participate in 2 treatment periods separated by a washout of at least 30 days between investigational product (IP) administrations in each period. Participants will be randomized to 1 of 2 sequences. Participants will be admitted to the clinical unit on day -1 of each period and will be residential for 5 days/4 nights. Participants will receive a single dose of isavuconazonium sulfate IV solution via NG tube (test formulation) or isavuconazonium sulfate capsules for oral administration (i.e., oral capsules administered to nonintubated participants) (reference formulation) under fasting conditions on day 1 of each period. Participants are to remain semirecumbent and avoid lying on either the left or right side for 4 hours postdose. Correct placement of the NG tube will be confirmed using X-ray radiography. Pharmacokinetic samples will be collected predose on day 1 of each period and at multiple time points postdose. Standard safety and tolerability assessments will be conducted. Participants will be discharged from the clinical unit on day 4 of each period on the condition that all required assessments have been performed and that there are no medical reasons for a longer stay in the clinical unit. Participants will return for ambulatory visits to collect pharmacokinetic samples on days 8, 11, 15 and 21 of each period.~The study will be completed with an end-of-study visit (ESV). The ESV will take place 5 to 9 days after day 21 of period 2 or at early discontinuation from the study.
The purpose of this study is to evaluate the bioequivalence of isavuconazole following a single dose of isavuconazonium sulfate intravenous (IV) solution via nasogastric (NG) tube (test formulation) compared to a single dose of isavuconazonium sulfate capsules for oral administration (i.e., oral capsules administered to nonintubated participants)(reference formulation). In addition, this study will evaluate the safety and tolerability of isavuconazole and the general pharmacokinetic (PK) parameters of isavuconazole when administered as a single dose of isavuconazonium sulfate IV solution via NG tube (test formulation) and a single dose of isavuconazonium sulfate capsules for oral administration (i.e., oral capsules administered to nonintubated participants) (reference formulation) under fasting conditions in healthy male and female participants.