"Clinical Trial Endpoints and Therapies in Polycystic Kidney Disease"
FDA & PKD Foundation Workshop
May 17, 2007

The Food & Drug Administration and the PKD Foundation co-sponsored a workshop in Washington, D.C., on May 17, 2007, that discussed outcome measures in clinical trials for PKD patients. The Workshop engaged the federal regulatory community, PKD clinicians and research scientists and pharmaceutical companies in a discussion of new endpoints appropriate for PKD patients in clinical studies of possible therapeutics to slow or stop disease progression.

The standard measure of kidney function, glomerular filtration rate (GFR) is accepted as an outcome measure in clinical trials for kidney drugs. GFR remains stable in PKD patients over a long period of time while the disease progresses because the non-cystic tubules are able to compensate for the loss of normal tissue. However, as cysts continue to form and enlarge, eventually there is not enough normal tissue left and GFR drops rather precipitously. When the measured GFR begins to fall, it is too late for therapeutic interventions to slow or stop the disease.

Because of the problem of using GFR as an outcome measure in PKD patients, the Workshop presentations (linked below) demonstrated the use of kidney and cyst volume measures in PKD patients as indicators of disease progression. The presentations were excellent and stimulated much discussion among the attendees and the speakers. One important result of the Workshop is that a dialogue has been opened between PKD clinicians and scientists and the FDA to further discuss cyst and kidney volumes and other measures of benefit in PKD clinical trials.

Please click on the following links to view the Workshop presentations:

"FDA Regulatory Perspective" (PDF)
Norman Stockbridge, M.D., Ph.D.

"Autosomal Dominant Polycystic Kidney Disease" (PDF)
"Clinical Stages of ADPKD" (PDF)
Ronald D. Perrone, M.D.

"Autosomal Recessive Polycystic Kidney Disease" (PDF)
Lisa Guay-Woodford, M.D.

"Biology and Pathology of the Cyst" (PDF)
Arlene Chapman, M.D.

"Volume as an Endpoint in PKD" (PDF)
Vicente Torres, M.D., Ph.D.

"Utility of MRI in the Assessment of Renal Volume in Children" (PDF)
Melissa Cadnapaphornchai, M.D.

"MRI Techniques for Volume Estimation in Polycystic Kidney Disease" (PDF)
Kyongtae Bae, M.D., Ph.D.