Study leader to present tacrolimus grant to the Food and Drug Administration, American Society of Transplantation and American Society of Transplant Surgeons Monday, Oct. 22, in Washington, D.C.
A new study at the University of Cincinnati (UC) seeks to end the questions over generic-vs.-brand for a common immunosuppressive drug for transplant patients, tacrolimus.
Rita Alloway, PharmD, UC research professor of medicine and director of transplant clinical research within the UC Department of Internal Medicine, has received a $2.7 million U.S. Food and Drug Administration grant to run a clinical trial studying the immunosuppressant tacrolimus (Prograf) against two other generic manufacturers in liver and kidney transplant patients.
Tacrolimus is a "cornerstone drug" in post-transplant immunosuppression, used after transplant to reduce the activity of the patient's immune system and lower the risk of rejection. It's also a critical dose drug-a medication in which the dosage level between efficacy and unwanted side effects is very close.
"Most immunosuppressant drugs require individualized dosing and careful management to ensure the proper blood concentrations are maintained," says Alloway. "Too high exposure to these drugs increases the risk of toxicity, over-immunosuppression and cancer in patents. Too low exposure may lead to rejection of the organ by the patient's immune system."
Alloway says these conditions have led transplant physicians and their patients to be wary of using generic immunosuppressants-concerned that the quality, pharmacokinetics and therapeutic efficacy of these new drugs may differ from the branded, or innovator, product.
Her study aims to address these concerns in a prospective, blinded, six-way crossover study in kidney and liver transplant patients testing whether the two most disparate generics, based on potency, purity, and dissolution ( "Generic Hi" and "Generic Lo"), are bioequivalent to the innovator version in stable transplant patients.
"Currently more than 50 percent of transplant patients are dispensed generic tacrolimus," says Alloway. "The largest concern for clinicians is the switchability between various generics. When patients receive their prescription, they could be getting medication from different manufacturers each month. We're investigating whether even the most disparate generics have the same efficacy in healthy post-transplant patients."