Safety and efficacy of recombinant human erythropoietin treatment of non-motor symptoms in Parkinson's disease

Abstract

Objective: Numerous animal studies and clinical trials have demonstrated that erythropoietin (EPO) has therapeutic effects in ischemic and degenerative diseases. However, there have been few clinical trials to investigate the effect of EPO in Parkinson’s disease (PD) patients. This study was an exploratory pilot study to investigate the effects of recombinant human EPO (rhEPO) on motor and non-motor symptoms (NMS) in PD patients.Methods: A total of 26 PD patients at the Hanyang University Hospital were enrolled in the study. The participants were randomly assigned to rhEPO and placebo groups. The rhEPO group was infused intravenously (40000 IU each) twice a week for 5 weeks. Clinical improvement was estimated using the United Parkinson's Disease Rating Scale-III (UPDRS-III), the NMS scale (NMSS) and the 39-question Parkinson’s Disease Questionnaire (PDQ-39). [18F] N-(3-fluoropropyl)-2β-carbon ethoxy-3β-(4-iodophenyl) nortropane (FP-CIT) photon emission tomography (PET) scan was performed on each participant at baseline and again after 12 months.Results: The rhEPO administration significantly improved the NMSS and PDQ-39 scores at 12 months. The UPDRS-III, which reflected motor function, did not change significantly after the rhEPO treatment. With the NMSS, the domains of cardiovascular autonomic function, sleep/fatigue, mood/cognition and attention/memory showed significant changes. None of the participants experienced any serious adverse effects.Conclusions: We found that rhEPO had beneficial effects on NMS but not on motor function. Dopaminergic refractory NMS, such as cardiovascular autonomic dysfunction and cognition, showed improvement after the administration of rhEPO. Our results suggest that rhEPO might be a good candidate for the overall treatment of NMS in PD patients.