The European Medicines Agency (EMA) is based in London's Canary Wharf, sitting amidst the skyscrapers of international financial groups. Here, new drugs go through a scientific assessment. The results are then sent to the European Commission in Brussels, which decides whether or not to authorize the drug's use across member states. Each state has its own national regulatory agency, but the EMA reviews the safety of all medicines.

The future of this system is yet another thing that is deeply uncertain as Britain hurtles towards Brexit. The EMA will leave London when Britain leaves the EU - and as the EMA is subject to the European Court of Justice, the British government has indicated that it will leave it. But it is not clear whether the UK will have to develop its own system for drugs approval.

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Although regulatory frameworks are hardly the most exciting topic for discussion, changes to this system could have an immediate and serious impact on people's lives. "This background stuff - the process by which drugs are approved and distributed - is absolutely vital to how things are run," says Jennifer Erskine, a London-based medical researcher. "We're living in a time of medical breakthroughs, so it matters how quickly new treatments get approved, and the mechanisms by which they get there."

In July, pharmaceutical leaders sent a letter to the UK's Brexit minister, David Davis, and the EU's chief negotiator, Michel Barnier, warning that the supply of life-saving medicines in both Europe and the UK could be severely disrupted: "In the case of a disorderly withdrawal, there is a risk that all goods due to be moved between the UK and EU could be held either at border checks, in warehouses or manufacturing and/or subject to extensive retesting requirements."

Alternate systems

Some experts have raised concerns that if Britain has to develop its own approvals system, the UK may be last in the queue for new medicines as drug companies will focus on securing approval in bigger and more lucrative markets. "Faced with a choice of access to a market of patients across the whole of the EU, or limited to the UK, pharma companies will act rationally and choose the EU, or at least the EU first. We will come later, with New Zealand or Canada," says Tamara Hervey, professor of EU law at Sheffield University.

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There is also the question of whether the Medicines and Healthcare Products Regulatory Agency, the British body that would replace the EMA, can cope. Mike Rawlins, head of this regulator, said recently that he was "hoping and praying" that Britain would remain in the EU.

This is big business: in Britain, the life sciences industry generates more than £60 billion (66 billion euros) a year and supports 220,000 jobs. Scientists have warned that it might be difficult for British researchers to continue to take leading roles in collaborative EU projects looking into cures for cancer or HIV.

Yet for many, the most pressing concern is patient safety being affected by changes in regulation. "I worry about the delay of life-saving drugs, and potentially the additional costs, I worry about this being an extra factor in the [priorities] of the UK not only for making drugs available but research and development as well," says Professor Paul Workman, president of the Institute of Cancer Research.

Next steps

Some indication of how seriously this issue is being taken in the UK is evident in the fact that in early July in a letter to the Financial Times newspaper, Health Secretary Jeremy Hunt and Business Secretary Greg Clark called for continued collaboration with the EU on drugs "in the interests of public health and safety." This was highly unusual as it amounted to ministers spelling out their negotiating position before talks have begun in earnest.

The pharmaceutical industry wants the UK to continue to participate in the EMA's initial assessment process. Under this plan, once a recommendation has been made, separate but identical proposals would be sent to Brussels and London for authorization. This would allow the UK government to make a decision separately to that of the European Court of Justice.

"The worst-case scenario is that we crash out of the EU and that amidst the scores of regulatory frameworks that need to be replaced, this crucial issue gets drowned out," says Erskine. "In that scenario, we could see lives being lost."

Twenty countries have so far offered to host the EMA and its 900 highly skilled workers once it leaves its base in Canary Wharf. As with every other aspect of Brexit, exactly what relationship Britain will have with it after this point is still up in the air.

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