CLINICAL TRIALS ON PAR KINSON'S DISEASE

Christopher Goetz, MD, Rush University Medical Center, Chicago, Illinois, USA, presented an overview of findings from recently published clinical trials on Parkinson's disease (PD). He emphasized that there have been many new trials over the past year with a focus on both motor (Table 1) and nonmotor (Table 2) aspects of the disease, as well as a broad range of treatments, pharmacologic, surgical, and otherwise.

Dr. Goetz limited his discussion to randomized clinical trials with larger samples or particularly novel approaches, published since the 2013 International Parkinson and Movement Disorder Society (IPMDS) meeting in Sydney, through May 15, 2014, as well as studies being presented at the 2014 meeting. Dr. Goetz ended his presentation by highlighting that 383 active trials were underway as of May 15, 2014, with 335 in or near recruitment and 48 with recruitment completed. These trials are focused on old drugs for new indications, new drugs, novel interventions, and surgical therapies.

CLINICAL TRIALS ON OTHER MOVEMENT DISORDERS

Recent clinical trials on other movement disorders were presented by Werner Poewe, MD, Innsbruck Medical University, Innsbruck, Austria. Like Dr. Goetz, he limited his discussion to larger randomized trials published since the 2013 IPMDS meeting through May 27, 2014 (Table 3). These trials included patients with atypical parkinsonism (eg, parkinsonism due to multiple system atrophy, progressive supranuclear palsy, Huntington's disease, dystonia, and essential and other tremor disorders).

ONGOING TRIALS: CHALLENGES

The session ended with a presentation by Joaquim Ferreira, MD, PhD, University of Lisbon, Lisbon, Portugal, on what to expect from ongoing clinical trials, including current challenges and their influence on future trial design.

Prof. Ferreira emphasized that there is a gap in pharmaceutical interventions for PD, with no new licensed drugs specifically for PD since the United States Food and Drug Administration approved rivastigmine in 2007. Although most clinical trials underway since June 2013 are primarily examining the safety and efficacy of pharmaceutical agents, the number of clinical trials aimed at nontraditional interventions, such as physiotherapy and exercise, has increased substantially. The rationale behind this is reflected in the primary outcome used in most studies since June 2013: the effect of the intervention on gait, balance, and falls.

Those designing future clinical trials need to learn from prior clinical trials to improve design. Design elements that will validate the study have to be incorporated into the early stages of trials, such as the use of active controls, and trials must focus on more than just the type of intervention. Prof. Ferreira emphasized that when designing future clinical trials, researchers need to keep in mind what really matters most to the patient. What are the determinants of improving functional status, health-related quality of life, and perceived health status? As PD is a slowly progressive disease, there are further considerations of the different treatment goals for early versus later stages of disease.

Finally, Prof. Ferreira highlighted the need for researchers of future trials to consider the type of patients to recruit and the broad spectrum of issues needed to consider when choosing patients, including types of markers, stage of disease, and route of administration. As an example of the importance of properly selecting patients for future clinical trials, he noted that registries of ongoing fall-related clinical trials in PD patients show that patients with cognition problems are excluded from many of these trials, despite the fact that cognition problems and falls are often connected.