Name: Emcitate (tiratricol) in MCT8 deficiency: Pharmacokinetics
Published: 2026-09-14T15:39:06-04:00

Product information and disease description Product description Product information Pharmacology

Pharmacokinetics

5 evidence topics · 4 sources

Pharmacokinetic parameters: prescribing information

Parameter	Prescribing information
Dose proportionality	“The area under the plasma concentration-time curve (AUC) and maximal plasma concentration (Cmax) of tiratricol increased dose proportionally over the dose range studied (175 mcg to 1050 mcg) after oral administration.”
Enteral tube administration	“Administration of EMCITATE via an enteral tube compared to standard oral administration did not affect tiratricol pharmacokinetics.”
Absorption	“The absorption of tiratricol is rapid with a median time to maximum plasma concentration (Tmax) of 0.5 hours (range 0.25 to 1 hour).”
Plasma protein binding	“Tiratricol plasma protein binding is 99%.”
Apparent volume of distribution	“The apparent volume of distribution is 364 L for a 70 kg patient and 130 L for a 25 kg patient.”
Apparent clearance	“The apparent clearance of tiratricol is 21 L/hr for a 70 kg patient and 10 L/hr for a 25 kg patient.”
Steady-state half-life	“The steady state half-life is approximately 12 hours for a 70 kg patient and 9.4 hours for a 25 kg patient.”
Metabolism	“Tiratricol is metabolized by stepwise deiodination, sulfation and glucuronidation, mainly in the liver.”
Excretion	“Tiratricol and its metabolites are predominantly eliminated in urine as inorganic iodine and in bile.”

Effect of food: prescribing information

“Administration of EMCITATE in healthy volunteers at doses of 175 mcg and 1050 mcg with a high-fat high-calorie meal (956 kcal energy, 35 g protein, 65 g carbohydrate and 61 g fat (with 57% energy from fat)) resulted in a delayed Tmax (1 hour), reduced Cmax (67%-70%), and unchanged AUC, compared to fasted conditions.” (opens the prescribing information at this quote)
“These changes are not clinically significant” (opens the prescribing information at this quote)

Healthy-volunteer bioequivalence, food-effect, and dose-proportionality study

“This study investigates the pharmacokinetics (PK) of tiratricol.” (opens the source at this quote in a new tab)
“This novel Phase 1, randomized, five-period cross-over study was a hybrid combination of a two-period cross-over and a three-period balanced incomplete block design in healthy adult male subjects (n = 30) with a washout of ≥3 days between periods.” (opens the source at this quote in a new tab)
“Bioequivalence was established between 350μg tiratricol oblong and 350μg tiratricol round tablets in terms of AUC and Cmax with a serum half-life of approximately 13h for both administrations.” (opens the source at this quote in a new tab)
“Overall exposure (AUC) was comparable between the fasted and fed state.” (opens the source at this quote in a new tab)
“Absorption was rapid in the fasted state (median Tmax 0.5 hr) but slower in the fed state (median Tmax approximately 1.5 hr), with Cmax 67–70% lower.” (opens the source at this quote in a new tab)
“Cmax following treatment with the 175μg, 350μg, and 1050μg oblong tablet doses increased proportionally with increasing dose, whereas AUC increased in a slightly greater than proportional manner with increasing dose.” (opens the source at this quote in a new tab)
“Tiratricol was well tolerated in all doses and fasting states, with no serious adverse events recorded.” (opens the source at this quote in a new tab)

Population pharmacokinetics in patients and accumulation

“The applicant analysed PK measurements from 10 patients from the ReTRIACt study with the Population PK modelling. The Population PK modelling of the ReTRIACt data supports that in patients tiratricol PK is similar to healthy volunteer PK.” (opens the source at this quote in a new tab)
“The Population PK model predicts some accumulation of AUC and Cmax when comparing a single administration versus steady state. However, accumulation ratios based on the same dose frequency on day 1 to steady state are modest (≤1.5) regardless of dose frequency, dose and body weight, consistent with the relative short half-life of tiratricol.” (opens the source at this quote in a new tab)
“No formal clinical study to investigate the impact of special populations on tiratricol PK has been conducted.” (opens the source at this quote in a new tab)
“The available data indicate a weight dependence of PK.” (opens the source at this quote in a new tab)

Pharmacokinetics: European summary of product characteristics

“The in vitro plasma protein binding of tiratricol is high, with protein binding of > 99% in human plasma. The bioavailability of tiratricol (F) was 67 ± 6% suggesting tiratricol is well absorbed from the gastrointestinal (GI) tract.” (opens the source at this quote in a new tab)
“The geometric mean t½ was between 13.3 – 14.0 hours for the 350 microgram and 1 050 microgram doses, respectively. Tiratricol is eliminated through bile and urine.” (opens the source at this quote in a new tab)