%0 Journal Article
%T Effect of Hepatic Impairment on Trofinetide Exposures Using an In Silico Physiologically Based Pharmacokinetic Model.
%A Darwish M
%A Obianom ON
%A Youakim JM
%A Darling I
%A Lukacova V
%A Bradley H
%J Adv Ther
%V 0
%N 0
%D 2024 Jul 4
%M 38963587
%F 4.07
%R 10.1007/s12325-024-02926-6
%X <B>BACKGROUND: </B>Trofinetide is the first drug to be approved for the treatment of Rett syndrome. Hepatic impairment is not expected to affect the pharmacokinetic (PK) profile of trofinetide because of predominant renal excretion. This study was conducted to help understand the potential impact of any hepatic impairment on trofinetide PK.<BR><B>METHODS: </B>This study used physiologically based PK modeling to estimate trofinetide exposure (maximum drug concentration and area under the concentration-time curve from time zero to infinity) in virtual patients with mild, moderate, and severe hepatic impairment (per Child-Pugh classification) compared with virtual healthy subjects following a 12 g oral trofinetide dose.<BR><B>RESULTS: </B>In individual deterministic simulations for matched individuals and stochastic simulations at the population level (100 virtual individuals simulated per population), as anticipated, predicted plasma exposures were similar for healthy subjects and for patients with mild, moderate, and severe hepatic impairment. However, predicted blood concentration exposures slightly increased with increasing severity of hepatic impairment because of change in hematocrit levels.<BR><B>CONCLUSIONS: </B>This study indicates that hepatic impairment is not expected to have a clinically relevant effect on exposure to trofinetide.<BR>Trofinetide is the first approved treatment for Rett syndrome, a rare genetic condition that affects brain development. When a person takes trofinetide, most is removed from the body via the urine in its unchanged form (no chemical alteration). Regulatory requirements mean researchers must confirm the safety of any pharmaceutical drug and evaluate whether changes in liver function lead to harmful levels of drug exposure. Researchers used a computer model to predict how much trofinetide would be present in the blood and plasma (the liquid portion of blood) over time in virtual healthy subjects and virtual patients with varying degrees of liver disease (mild, moderate, or severe). Computer simulations showed that predicted trofinetide levels in plasma were similar in virtual healthy subjects and each virtual patient group with liver disease. Predicted levels of trofinetide in blood were slightly elevated with increasing severity of liver disease. This is because people with liver disease have fewer red blood cells, so the cell portion of blood becomes smaller relative to the liquid portion (plasma), which leads to higher trofinetide concentrations in whole blood (trofinetide minimally enters the red blood cell). The small increase in trofinetide levels in blood and the absence of any change in trofinetide levels in plasma means that people with Rett syndrome and liver disease are unlikely to be exposed to harmful levels of trofinetide after a 12 g oral dose.