Pfizer Inc. (NYSE:PFE) announced today top-line results from a Phase 3B/4 study of RAPAMUNE® (sirolimus) evaluating kidney transplant patients who transitioned from tacrolimus-based therapy (TAC) to RAPAMUNE® 3 to 5 months after transplant. The primary endpoint of the study was not achieved as there was not a statistically significant difference in renal function improvement between patients who continued receiving TAC and those who switched to RAPAMUNE®.
For patients who were switched to RAPAMUNE®, 33.7% of patients achieved the primary endpoint of a ≥ 5 ml/min/1.73m2 renal function improvement based on glomerular filtration rate (GFR) from randomization to 24 months post-transplantation and 42.3% of patients continuing to take TAC achieved the primary endpoint (p=0.239).
The study was an open-label, randomized, comparative, multi-center, multi-national study conducted in Europe, Latin America, North America, and the Pacific Region. There were 256 subjects randomized at 3 to 5 months after transplant, with two subjects not receiving any medication. Group I included 131 subjects receiving RAPAMUNE®; the dose was adjusted to sirolimus blood levels of 7-15 ng/mL during the first year post-transplantation and 5-15 ng/mL thereafter. Group II, the control group, included 123 subjects who continued receiving the same TAC-based treatment that was being administered prior to randomization. Subjects in both groups were evaluated at a pre-randomization visit, at the day of randomization, 4-weeks after randomization, and 6-, 12-, 18- and 24-months post transplantation.
The study also evaluated the safety of RAPAMUNE® and the adverse events observed in the study were consistent with the known safety profile of RAPAMUNE®. The results of this study are expected to be submitted for presentation at upcoming scientific congresses and for publication in peer-reviewed medical journals.In the United States, RAPAMUNE® is indicated for the prevention of organ transplant rejection in kidney transplant patients aged 13 years and older. Important RAPAMUNE® Safety Information There is an increased risk of developing infections or certain cancers, especially lymphoma and skin cancers. RAPAMUNE® has not been shown to be safe and effective in people who have had liver or lung transplants. Serious complications and death may happen in people who take RAPAMUNE® after a liver or lung transplant. You should not take RAPAMUNE® if you have had a liver or lung transplant without talking with your doctor. Do not take RAPAMUNE® if you know you are allergic to sirolimus or any of the other ingredients in RAPAMUNE®. Symptoms of an allergic reaction include swelling of your face, eyes, or mouth; trouble breathing or wheezing; throat tightness; chest pain or tightness; feeling dizzy or faint; and rash or peeling of your skin.