UQ team develop model for correct drug use for child transplant recipients

University of Queensland researchers have developed a mathematical model to ensure correct anti-rejection drug dosages for babies and children receiving liver transplants.

The research team, headed by School of Pharmacy head Professor Susan Tett, discovered children receiving cut-down adult liver transplants had a slower metabolism than those receiving rarely donated child livers.

"In other words, children receiving a part of an adult liver could not process drugs through their bodies at the same rate as young patients receiving children's livers and were at risk of accumulating immunosuppressant drugs in their systems over time," she said.

The preferred immunosuppressant for these children, tacrolimus, must be administered just after surgery and then twice a day for their rest of their lives. Too little of the drug can result in liver rejection and potential death while too much can have unpleasant side-effects including seizures, according to Professor Tett.

"Adult livers are more commonly donated for transplant with only a third of one liver required for babies and young children and two-thirds then available for transplant into an adult recipient," she said.

Funded by a three-year, $142,000 National Health and Medical Research Council grant, researchers analysed data from 35 cases of babies receiving liver transplants through Brisbane's Royal Children's Hospital.

The mathematical model of drug clearance rates from child liver transplant recipients is being further tested before a computer model is developed for doctors and surgeons to assist in choosing the correct drug dose.

"Doctors will eventually be able to type variables such as whether the donor liver is from an adult or child as well as patient details such as weight into the program and be given the optimal drug dosage," Professor Tett said.

The research team included Queensland Liver Transplant Unit Director Associate Professor Steve Lynch, Princess Alexandra Hospital scientists Paul Taylor and Paul Salin, Pharmacy School PhD student Christine Staatz and research assistant Charlene Willis.

The same UQ team in conjunction with PA Hospital clinical pharmacologist Dr Peter Pillans have also developed a strategy for monitoring and determining optimal dosage of the immunosuppressant drug mycophenolate mofetil in adult kidney transplant recipients.

For more information, contact Professor Susan Tett (telephone 07 3365 3191, email s.tett@pharmacy.uq.edu.au) or Shirley Glaister at UQ Communications (telephone 07 3365 2339).

Enquiries can also be directed to communications@mailbox.uq.edu.au