What Your Tier 1 Supplier Map Might Be Missing

A conversation between David Fairnie, Principal Consultant, BSI Group, and Elizabeth Urbanek, Executive Editor, Clinical Supply Leader

A clinical supply team may know its Tier 1 suppliers, but that doesn’t necessarily mean it knows all of the dependencies behind them. Two suppliers that look independent on paper may rely on the same manufacturer, specialist input, infrastructure, or transportation hub.

Those dependencies can become much more important when conditions change. A shipment may be diverted to a different airport, a qualified packaging component may become unavailable, or a power disruption may affect manufacturing, testing, or product release. In each case, the question is not just whether a supplier has a contingency plan, but whether that plan addresses the dependencies that could actually stop supply.

In this Q&A, David Fairnie, principal consultant at BSI Group, discusses some of the dependencies clinical supply teams may be missing and what they can do to better understand where their supply chains could be vulnerable.

1. When clinical supply teams map their Tier 1 suppliers, what risks or dependencies are they most likely to miss?  

A Tier 1 supplier map shows who you buy from; a dependency map shows what can stop supply. Independent suppliers may rely on the same manufacturer, specialist input, or infrastructure. That concentration can undermine diversification.

Low-spend suppliers are also easily overlooked, even when their products or services are difficult to replace. Ask what must keep functioning for the product to reach the clinical site, where those dependencies converge, and whether the map is current enough to support decisions when disruption hits. 

2. Cold chain is an obvious critical dependency, but what vulnerabilities can exist beyond the temperature-controlled shipment itself, particularly when infrastructure or transport conditions change?  

The vulnerability often sits at a handover point or on a contingency route. A refrigerated clinical shipment diverted to another airport may face longer customs delays without suitable cold storage, exceeding its qualified shipping duration. Power, refrigerant availability, handling staff, and local transport all matter. Teams should check whether contingency arrangements can support the product throughout the revised journey, including delays, and establish who can intervene. A route that works under normal conditions may not remain viable during disruption. 

3. Packaging is often treated as a relatively straightforward part of clinical supply. What happens when packaging materials, specialized components, or packaging capacity become constrained?  

Packaging constraints can leave usable product unable to reach a trial site. A shortage of a qualified vial stopper, for example, cannot necessarily be solved by ordering a similar component: the replacement may require compatibility assessment, qualification, and regulatory review. Specialist packaging capacity can be equally difficult to replace. Treat packaging as a critical supply dependency. Prequalify alternatives where possible, confirm that capacity is genuinely available, and understand which changes would trigger requalification or regulatory approval. 

4.  How can energy disruptions affect clinical supply operations in ways that may not be immediately visible on a supplier risk map?  

Energy disruption can interrupt manufacturing controls, laboratory testing, product release, and distribution systems, as well as refrigeration. Backup power only helps if it supports the critical processes for long enough and fuel can be replenished. Recovery may also take longer than the outage because equipment and controlled environments need checks before operations resume. Ask suppliers which activities can continue, how long they can operate independently, and how quickly they can restart safely. That reveals exposure that a supplier location alone cannot show. 

5.  What role do specialist inputs and lower-tier suppliers play in creating vulnerabilities that clinical supply teams may not discover until a disruption occurs?  

A specialist input can have a low purchase value but a high consequence if it becomes unavailable. Lower-tier dependencies are particularly difficult to spot when there is only one qualified source, limited capacity, or a lengthy approval process for alternatives.

Start with the products and processes whose interruption would most affect trial continuity, then trace their essential inputs upstream. The aim is to identify the dependencies that could stop supply and agree practical recovery options with the suppliers involved. 

6. Transport corridors can look like logistics issues rather than supply chain dependencies. What should clinical supply teams be asking about their routes, and how can they determine whether an alternative route actually reduces risk? 

Ask what each route depends on, how quickly it can be switched, and whether usable capacity exists. Two routes may share the same hub, border crossing, handling provider, or chokepoint, leaving both exposed to one failure. An alternative must still meet the product's temperature, security, and transit time requirements under disruption. Test it through scenario exercises and, where practical, test shipments. The real test is whether it removes a shared failure mode, rather than simply creating a second line on the map.

About the Expert: 

David Fairnie is a principal consultant at BSI Group, specializing in supply chain security and organizational resilience. He works with global life sciences organizations on supply chain risk, resilience strategy, and crisis preparedness.