Parkinson’s disease is the second most common neurodegenerative disorder next to Alzheimer’s.1

There are approximately one million people in the United States and 10 million people worldwide living with the disease. Moreover, this progressive degenerative disorder usually manifests after 50 years of age — although, about 10 percent of the cases are detected before age 50.2

The typical motor impairments associated with Parkinson’s —namely bradykinesia (slow initiated voluntary movements), muscular rigidity, resting tremor and postural issues3,4 — result from the degenerative loss of dopamine-producing cells in the midbrain.1,5 In fact, more than 60 percent of these cells are lost before the onset of physical symptoms.5

Presently, drugs that substitute dopamine levels in the brain, such as levodopa and dopamine-agonists, are most commonly prescribed to manage the symptoms of Parkinson’s. Nevertheless, these drugs do not mitigate the progression of the disease.6,7 Alternative therapies have also been studied, including transcranial or deep brain stimulation, the restorative implantation of stem cells and disease-modifying therapies which reduce the amount of potentially neurotoxic protein aggregates, the alpha- synuclein. Also home-based exercises designed to help individuals to cope with the disease are evaluated in trials.

Effectively evaluating these alternative interventions depends on patient participation in the clinical trials. However, these trials have logistical challenges related to recruitment and trial retention, which are directly affected by the disease. For example, those with more progressed forms of Parkinson’s will have trouble participating because of limited mobility to travel to clinics, even though alone in the US, multiple ten-thousands of patients with PD are registered in the Michael J Fox Foundation’s trial registry and waiting for an option to participate in a study. Ensuring these patients’ have access to trials calls for steps that allow them to effectively participate at home. Therefore, expanding in-home services could help in Parkinson’s disease research, overall, by increasing participation and retention in clinical trials.

Why in-home services are increasingly important

In-home services gained more momentum with the onset of the COVID-19 pandemic, forcing clinical trials to adapt because of concerns over vulnerable populations contracting the virus as well as limited access to sites. Some patients involved in clinical trials are elderly and/or may have compromised immune systems — which is especially true in Parkinson’s disease trials. For this reason, many potential patients have opted not to participate, causing these trials to come to a halt because of the logistical hurdles.

However, such hurdles must be addressed to keep studies running. If the participant cannot get to a clinical site due to either health issues or inconvenience, there needs to be an efficient way for the study to come to the patient. This could include using decentralised trials and/or providing in-home services either through telemedicine or by having a healthcare professional physically come to the participant’s home to collect biological samples, to check vitals or to help the participant in another manner related to the study. This would increase study compliance and keep participants safe and engaged during the pandemic and beyond.

Study reveals what clinical trial participants really want

Patients have consistently rated alternative access to clinical trials favorably. An ICON survey of 3,800 patients between the ages of 18 to 75+ — with most being above 55 years of age — revealed that clinical study participants want more options. Specifically, when asked where they would prefer a study to take place, the majority selected a combination of study site and either telemedicine or in-home services. Interestingly, a majority said they would participate in a clinical trial if all visits were done virtually. Finally, 72 percent were more willing to participate using technology, such as wearables and mobile devices, in addition to patient diaries.

Location seemed to be a key factor in determining participation. Only 10 percent of those surveyed said that they would travel one hour or more to participate in a clinical trial. A majority, (59 percent) said they were more willing to be part of a clinical trial if logistical support were given. Therefore, the key is to make it easy for participants and sponsors to connect either at the participant’s location or at a clinical site conveniently located.

Changing how clinical services are provided

As more Parkinson’s disease studies use alternative therapeutic strategies that require additional involvement from the patient, researchers need to start thinking beyond traditional on-site clinical participation. Specifically disease-modifying and restorative concepts often require  longer periods of patient involvement, up to several years. Taking advantage of technologies, such as wearables and mobile devices, to provide instruction and collect data can make this possible.

Also, providing in-home services by a healthcare professional makes it easier for participants to stay engaged and can increase the depth and breadth of the study by including individuals who would not typically be able to participate through traditional on-site means. In the end, in-home clinical services offer a solution to some of the major challenges faced by Parkinson’s disease trials including patient mobility impacting travel/access to sites.

For more information about how In-home Services can help your clinical trial, please visit ICON’s in-home services website.

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  1. Alexander, Garrett E., Biology of Parkinson’s Disease: pathogenesis and pathophysiology of a multisystem neurodegenerative disorder, Dialogues Clin Neurosci. 2004 Sep; 6(3): 259–280.
  2. Marras, C., et al., Prevalence of Parkinson’s disease across North America. npj Parkinson's Disease, 2018. 4(1): p. 21.
  3. Hughes, A.J., et al., Accuracy of clinical diagnosis of idiopathic Parkinson's disease: a clinico-pathological study of 100 cases. Journal of neurology, neurosurgery, and psychiatry, 1992. 55(3): p. 181-184.
  4. Sveinbjornsdottir, S., The clinical symptoms of Parkinson's disease. Journal of Neurochemistry, 2016. 139(S1): p. 318-324.
  5. German, D.C., et al., Midbrain dopaminergic cell loss in Parkinson's disease: computer visualization. 1989(0364-5134 (Print)).
  6. Müller, T., Dopaminergic substitution in Parkinson's disease. 2002(1465-6566 (Print)).
  7. Lees, A., Alternatives to levodopa in the initial treatment of early Parkinson's disease. 2005(1170-229X (Print)).