Supplying investigational product to decentralised participants

A site-based study solves investigational product supply once, at the site: a pharmacy receives, stores, and dispenses product under controlled conditions, with a paper or digital trail for every unit. A decentralised study has to solve the same problem for every individual participant's home, which turns one controlled logistics chain into as many separate ones as there are participants.

Work from the Trials@Home RADIAL proof-of-concept trial looked directly at what this actually requires in practice, and the findings are a useful corrective to an assumption that sometimes goes unexamined: that decentralised supply is simply "the same process, delivered by courier instead of collected at a site."

What actually gets harder

A few specific challenges consistently show up when investigational product supply moves into participants' homes:

• Temperature control without professional storage infrastructure. A pharmacy has validated refrigeration and monitoring built in. A participant's home has a domestic fridge, which is a meaningfully different environment to guarantee cold-chain integrity in.
• Confirming receipt and condition, not just delivery. A courier confirming a package was delivered isn't the same as confirming the product arrived in the condition it needs to be in, and the person best placed to notice a problem, the participant, may not know what to check for.
• Accountability without a pharmacist physically dispensing each unit. Drug accountability at a site is straightforward because a professional is present at the point of dispensing. At home, accountability depends on participant self-report and remote verification, which introduces genuinely different risks of error.
• Handling returns, unused product, and disposal. A site has established processes for this built into pharmacy operations. Coordinating the same thing across dispersed participant homes is a logistics problem the study has to design for explicitly, not assume will sort itself out.

What the proof-of-concept trial suggests actually works

The RADIAL trial's approach points toward a few practical mitigations worth building into any decentralised supply chain from the start:

1. Purpose-built shipping with active temperature monitoring, not just insulated packaging assumed to be sufficient, with a clear escalation process if a monitored excursion is detected.
2. A simple, guided receipt-confirmation process for participants, specific prompts about what to check (packaging integrity, any visible temperature indicator, expected quantity), rather than a generic "did it arrive" question.
3. Remote accountability logging built into the participant's normal workflow, so recording what was taken and when doesn't require a separate, easily-forgotten step.
4. A clear, participant-friendly returns and disposal process, communicated at the point of delivery, not left for the participant to figure out or ask about later.

Why this matters for anyone considering a fully or partially decentralised design

The lesson from this work isn't that decentralised supply is impractical. Real proof-of-concept trials are demonstrating it can be done reliably. The lesson is that it requires deliberate, specific design attention, exactly the same category of attention that pharmacy operations already receive at a traditional site, rather than being treated as an implementation detail that a good courier service will handle by default.

A study team considering a decentralised or hybrid design for a product with real storage or handling requirements needs to ask, explicitly and early: who verifies condition on arrival, how is accountability logged without a pharmacist present, and what happens to product that isn't used. None of these questions have an obvious universal answer, but all of them have a wrong answer, which is not asking them until after the study is already running.