BACKGROUND. Recombinant human PDGF-BB (rhPDGF-BB) reduces Parkinsonian symptoms and increases dopamine transporter (DAT) binding in several animal models of Parkinson’s disease (PD). Effects of rhPDGF-BB are the result of proliferation of ventricular wall progenitor cells and reversed by blocking mitosis. Based on these restorative effects, we assessed the safety and tolerability of intracerebroventricular (i.c.v.) rhPDGF-BB administration in individuals with PD.
METHODS. We conducted a double-blind, randomized, placebo-controlled phase I/IIa study at two clinical centers in Sweden. Twelve patients with moderate PD received rhPDGF-BB via an implanted drug infusion pump and an investigational i.c.v. catheter. Patients were assigned to a dose cohort (0.2, 1.5, or 5 μg rhPDGF-BB per day) and then randomized to active treatment or placebo (3:1) for a 12-day treatment period. The primary objective was to assess safety and tolerability of i.c.v.-delivered rhPDGF-BB. Secondary outcome assessments included several clinical rating scales and changes in DAT binding. The follow-up period was 85 days.
RESULTS. All patients completed the study. There were no unresolved adverse events. Serious adverse events occurred in three patients; however, these were unrelated to rhPDGF-BB administration. Secondary outcome parameters did not show dose-dependent changes in clinical rating scales, but there was a positive effect on DAT binding in the right putamen.
CONCLUSION. At all doses tested, i.c.v. administration of rhPDGF-BB was well tolerated. Results support further clinical development of rhPDGF-BB for patients with PD.
TRIAL REGISTRATION. Clinical Trials.gov NCT00866502.
FUNDING. Newron Sweden AB (former NeuroNova AB) and Swedish Governmental Agency for Innovation Systems (VINNOVA).
Gesine Paul, Olof Zachrisson, Andrea Varrone, Per Almqvist, Markus Jerling, Göran Lind, Stig Rehncrona, Bengt Linderoth, Hjalmar Bjartmarz, Lisa L. Shafer, Robert Coffey, Mikael Svensson, Katarina Jansson Mercer, Anton Forsberg, Christer Halldin, Per Svenningsson, Håkan Widner, Jonas Frisén, Sven Pålhagen, Anders Haegerstrand