ENDO: Coffee Does Not Impede Bioavailability of LT4 Solution

FRIDAY, June 17, 2022 (HealthDay News) -- Bioavailability is equivalent for a single oral dose of levothyroxine (LT4) sodium solution administered five minutes prior to coffee or under fasting conditions, according to a study presented at the annual meeting of the Endocrine Society, held from June 11 to 14 in Atlanta.

Kris Washington, Pharm.D., from Vertice Pharma in Berkeley Heights, New Jersey, and colleagues conducted a bioavailability study to assess the rate and extent of absorption of the oral LT4 solution administered with coffee compared to administration under fasting conditions in 40 healthy adults in a two-period, two-treatment, two-sequence, crossover study. In each study period, a single 600-μg oral dose of LT4 solution was administered five minutes before drinking 8 ounces of American coffee (without milk or sweeteners) or under fasting conditions. For 48 hours after drug administration, blood samples were collected for total T4. A 40-day washout period separated treatment periods.

The researchers found there were no serious adverse events or discontinuations due to adverse events. For baseline-adjusted LT4, the geometric LT4 solution mean ratio of area under the receiver operating characteristic curve 0 to 48 hours and maximum serum concentration were 93.98 percent and 95.99 percent, respectively. The corresponding 90 percent confidence intervals fell within the U.S. Food and Drug Administration acceptance range for bioequivalence.

"The results demonstrate that the absorption of levothyroxine sodium oral solution was not affected by the consumption of coffee, potentially offering patients and providers more dosing flexibility," Washington said in a statement.

This research was conducted by Vertice Pharma, the manufacturer of the oral levothyroxine sodium solution used in the study.

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