The NHS cold chain is about to be stress-tested by a new medicine

Gene therapies are some of the most complicated medical products given to patients. Usually they have to be delivered through an infusion in a specialist facility or require an operation that removes cells from the body, re-engineers them and returns them.

But a new treatment called Vyjuvek, approved by the Medicines and Healthcare products Regulatory Agency in May, is different. The gel is applied directly to wounds and has been authorised from birth for patients with dystrophic epidermolysis bullosa (DEB), a rare genetic condition that leaves skin fragile and prone to blistering because of a fault in the gene that helps hold its layers together. In a study of 31 patients, 67% of wounds treated with the medicine were completely healed at six months, compared with 22% treated with a placebo.

Removing the complexity of treatment has been replaced with a different kind of problem – delivering it to patients. Vyjuvek needs to be stored at -15°C to -25°C, but can be kept at 2-8°C for up to a month if a freezer is not available. It should not be refrozen once refrigerated. After preparation, administration syringes can sit at room temperature for up to eight hours or refrigerated for up to 48 hours.

That makes it an engineering problem.

“Gene therapies fundamentally change the cold chain model,” says Chris Carver, director at clinical homecare provider HealthNet. “We move from standard refrigerated distribution to ultra-low, precision-controlled pathways with near-zero tolerance for deviation.”

The NHS developed its capacity to transport vials of liquid at cool temperatures during the Covid pandemic and subsequent vaccine drive. But with Vyjuvek, it needs to know where every carton, vial and syringe is, how long they have spent at each temperature and when they were thawed to know whether a nurse, pharmacist, clinician, patient or parent is allowed to apply the medicine.

Tracking more than temperature is the challenge, Carver says. The NHS has some experience of this – NHS England already runs an Advanced Therapy Medicinal Products programme to prepare the health service for complex products such as Car-T cell therapies. The UK also has a network of Advanced Therapy Treatment Centres, coordinated with the Cell and Gene Therapy Catapult, to build the systems needed to deliver advanced therapies routinely across the NHS.

But Vyjuvek moves the distribution point from hospitals into dermatology clinics, pharmacies and homes. “The last mile is where complexity peaks,” says Carver. “You’re coordinating tightly timed preparation, transport and administration, often within very narrow windows.”

The biggest challenge in the last mile is accounting for human factors. Children with DEB may need regular treatment on wounds that reopen, while adults may need a schedule that fits around work or daily care.

“The biggest challenges aren’t isolated,” Carver says. “Ultra-low storage capacity, real-time monitoring, validated transport and highly trained staff all need to work together.” Whether there is a courier van stuck in traffic or a freezer door left ajar, that needs to be registered to ensure it does not affect the final product.

For treatments such as Vyjuvek, the margin for error is tiny. “With gene therapies, there’s effectively no margin for error,” Carver says. “Even minor temperature excursions can compromise a product, which makes proactive monitoring, validated processes and rapid escalation protocols absolutely essential.”

The lesson from vaccines, biologics and Car-T, Carver says, is that “standardisation, continuous monitoring and strong governance are key to reliability”. Just as important is coordination – the logistics providers, pharmacy teams, clinicians and specialist nurses have to behave less like separate services and more like parts of one engineered system – something that has traditionally been tricky for the NHS.

Coordination will become even more important as gene therapies become more common. Vyjuvek shows advanced therapy may be heading away from rare, centralised procedures towards repeatable, distributed treatment. The challenge, Carver says, is making sure the infrastructure adapts with that change too. “It becomes a highly coordinated system,” he says, “where reliability depends on every link in the chain.”