In short
- A sponsor developing an imaging study in Parkinsonian syndromes required a site strategy aligned to radiopharmaceutical manufacturing locations, as the investigational product had a short shelf-life of only several hours from manufacture to dosing
- PSI identified movement disorder clinics within a viable geographic range of planned contracted manufacturing organization (CMO) locations, aligning investigator expertise with product-delivery requirements
- When one planned manufacturing location in the Western US presented patient availability challenges due to the isolated geography, PSI proposed a referral network model designed to connect patients from more distant regions to a specialist site in the main city
- Site selection focused on centers experienced with DaT-scan and PET imaging capabilities, as required by the protocol
- These creative solutions to enable on-time enrollment provided a future framework for complex neuroscience protocols involving radiopharmaceuticals
The challenge
A sponsor planning an imaging study in Parkinsonian syndromes approached PSI with a significant operational constraint: The investigational product had a short shelf life and needed to be administered within less than half a day of manufacturing.
The requirement immediately influenced site strategy. Rather than selecting sites solely based on patient volume, or prior study experience, the program required alignment between CMO locations and movement disorder clinics capable of supporting the protocol.
The sponsor initially proposed several manufacturing locations across the US. PSI’s feasibility team evaluated those locations against existing movement disorder centers and neurology site experience to determine whether sufficient patient access and operational feasibility could be maintained within the product delivery window.
At the same time, the study targeted patients with Parkinsonian syndromes undergoing imaging assessment – making investigator specialization an important factor during site identification. The team therefore focused on identifying sites with movement disorder expertise and experience managing patients referred for advanced neurological evaluation.
Parkinsonian syndromes
Parkinsonian syndromes include progressive supranuclear palsy (PSP), multiple system atrophy (MSA), and corticobasal degeneration (CBD). While Parkinson’s disease is relatively common [1], Parkinsonian syndromes each have an incidence of about 1 in 100,000 [2]; these related syndromes are typically managed by movement disorder specialists.
Designing a geographically constrained site strategy
Using data from previous neuroscience studies, the team triangulated movement disorder clinics around proposed CMO locations to identify sites capable of operating within the required delivery timeframe. The objective was to align three factors simultaneously:
- Manufacturing location
- Product delivery feasibility
- Access to investigators experienced in movement disorders
PSI conducted blinded outreach with potential sites to assess investigator interest and to evaluate whether clinics were already seeing patients consistent with the study population.
The sponsor’s proposed manufacturing locations varied significantly in operational practicality – sites around Florida offered broad access to movement disorder clinics and large patient populations, while proposed CMO locations in the Mountain West presented greater geographic limitations because of lower population density and fewer nearby specialist centers.
Rather than treating this as a barrier, we evaluated how the study design could adapt operationally, while still remaining within the product delivery constraints.
Building a referral network around the CMO
Due to the limited patient pool serviced across the sites within the product delivery range of the manufacturing location, PSI recommended a referral network model centered around the main city.
In the Western United States, patients already travel long distances for sophisticated movement disorder care. We recognized that a referral network model centered on the CMO location could align with those existing care patterns, while staying within the product delivery constraints.
Rather than expanding the site footprint, this approach connected existing neurology practices with a centralized, specialist center, balancing the realities of the region with the investigational product’s delivery constraints.
Referral networks remain an underused opportunity for clinical trial recruitment, particularly for connecting patients in community or geographically distant settings with specialist research sites. Deliberately designed and operationally connected referral networks in neurology can be highly productive. Evidence from stroke and Parkinson’s research shows that structured referral networks can substantially extend recruitment reach, with one stroke trial achieving nearly 9x the monthly randomization rate of conventional sites [3], and another contributing 75% of included patients [4].
Aligning imaging capability with protocol requirements
As participating sites required access to PET imaging capabilities, during feasibility the team focused on identifying centers with the imaging infrastructure and operational familiarity needed to support the protocol requirements.
From a site strategy perspective, imaging capability was not treated as an unusual barrier, as many movement disorder centers already had experience coordinating PET imaging and DaT-scan workflows for patients undergoing neurological evaluation. The key was confirming imaging capability and availability (while keeping the broader focus on geographic feasibility and product delivery logistics).
Outcome and sponsor response
The program highlighted the importance of integrating manufacturing logistics, investigator specialization, and regional referral behavior early during feasibility planning for complex imaging studies involving a geographically constrained product delivery.
It also demonstrated how operational flexibility – including referral network development and targeted site identification – can help sponsors evaluate difficult feasibility scenarios without defaulting to large or unnecessarily dispersed site networks.
Contact PSI's team to discuss your neuroscience and radiopharmaceutical site strategy
Abbreviations
CBD, corticobasal degeneration;
DaT-scan, dopamine transporter scan;
CMO, Contract Manufacturing Organization;
CNS, central nervous system;
MSA, multiple system atrophy;
PET, positron emission tomography;
PSP, progressive supranuclear palsy;
References
1. Li, M., et al., Global burden of Parkinson’s disease from 1990 to 2021: a population-based study. BMJ Open, 2025. 15(4): p. e095610.
2. Lo, R.Y., Epidemiology of atypical parkinsonian syndromes. Tzu Chi Med J, 2022. 34(2): p. 169–181.
3. Kernan W.Y., et al. Neurology, 2009. (15):1345-51.
4. Verschuur C.V.M., et al. R. Trials, 2022. (1):141.
