Drug Interactions between betiatide and ivacaftor / lumacaftor

MONITOR: The administration of an organic anion transporter 1 (OAT1) inhibitor just prior to or concurrently with the radiopharmaceutical, technetium (Tc99m) mertiatide, may reduce its renal uptake and excretion as it is a substrate of this transporter. Delayed clearance could result in a misinterpretation of diagnostic study results. Clinical data is limited. One crossover study conducted in 12 healthy male volunteers (22-25 years old), compared the results of Tc99m mertiatide injection alone to those obtained after the subjects received a potent OAT1 inhibitor (probenecid 750 mg) 1 hour prior to the radiopharmaceutical injection. Probenecid administration prolonged the plasma clearance half-life of Tc99m mertiatide in the late phase (30-60 minutes post injection), from 24.4 +/- 9.9 minutes to 33.1 +/- 12.9 minutes. Similarly, the volunteer's Tc99m mertiatide blood concentrations were higher after treatment with probenecid, suggesting that renal excretion of the radiopharmaceutical was inhibited by the OAT1 inhibitor.

MANAGEMENT: Administration of an organic anion transporter 1 (OAT1) inhibitor just prior to or concurrently with technetium (Tc99m) mertiatide should be done with caution as it may delay excretion of the radiopharmaceutical and affect the efficacy of the diagnostic procedure. Dehydration and acidosis can also lead to prolonged elimination of Tc99m mertiatide, further impacting the efficacy of the diagnostic test. Refer to the product labeling or local protocols for guidelines on patient hydration.