Determining the Right Dose
A decades-long trend in prescribing hormonal contraceptives is to prescribe the lowest dose of estrogen possible to avoid unwanted side effects. But co-medications often cause estrogen or progesterone to be metabolized more quickly, leading to unintended pregnancies. Another common scenario is a co-medication causing metabolism to slow, leading to higher estrogen levels that increase the risk of weight gain, heart disease and stroke.
By inputting databases of clinical trials of hormonal control therapies into physiological-based pharmacokinetic, or PBPK, models, researchers can use computer simulation to evaluate drug interactions between hormonal control agents and other drugs.
Co-investigators Dr. Joshua Brown, an assistant professor of pharmaceutical outcomes and policy, and Dr. Almut Winterstein, a professor and chair of pharmaceutical outcomes and policy, will use real-world, pharmacoepidemiologic data to translate findings from the models to real-life patients to further identify clinically relevant drug interactions. Researchers can then determine appropriate dosage recommendations when administering with other interacting drugs. If a specific type of hormonal control agent interacts poorly with other drugs, prescribers can recommend an alternative therapy.
After identifying proper doses of combined hormonal contraceptives, UF researchers will continue to maintain a database of models, making them open source for other researchers to explore. At a yearly public workshop, the UF researchers will share study results.
“It is very exciting to be able to help improve the health care of a specific subset of the population. Here we’ll be able to provide information to drug labels that are often void of actionable information,” said Dr. Larry
Lesko, an emeritus professor of pharmaceutics and a co-investigator on the study.
Once researchers build the computer simulation models, they can change the model’s system and drug parameters to study hormonal contraceptive drug interactions among specific subsets of the population, and can include non-oral administered drugs.
“I think we have an outstanding opportunity and partnership with the Gates Foundation to focus globally on women’s health,” Schmidt said. “We will try to reach out to private industry for additional partnering and sharing of drug interactions data that may accelerate our research.”
Reprinted with permission from UF College of Pharmacy.
