Clinical drug research in chronic central neurodegenerative disorders

Several compounds developed the treatment of Alzheimer's disease and Parkinson's disease have been clinically unsuccessful. Suggested reasons for these failures have included heterogeneous symptom expression, inappropriate assessment of effects, safety and tolerability hurdles, short duration of disease-modifying trials, recruiting pressure on study centers, administrative and bureaucratic overload, and pooling results from trial centers in different health care systems with differing quality and therapeutic concepts. The solution to these problems will include reducing the costs of drug development, with a concomitant reduction of approval hurdles. Trial designs are influenced by ethics committees, health care officials, political administrations, and research scientists. None have direct contact with the treated patients. Approval of novel therapeutic agents lies in the remit of health care officials, whereby price plays a more dominant role than therapeutic efficacy. Patients and prescribing physicians, however, are better placed to act as arbiters of the efficacy, risks, and overall value of a new drug in practice.