UK Gets Halloween Extension, But Brexit is Still Scary

British Prime Minister Theresa May won a further delay from European leaders until Oct. 31 on the UK’s exit from the EU, leaving drugmakers no clearer about the ultimate impact of Brexit on the supply chain.

A hard Brexit—a divorce without any kind of agreement—would mean that drug companies used to testing their products in the UK will find themselves on the outside looking in, because EU law requires drugs to be tested in member countries.

The uncertainty is already taking a toll on the industry. UK regulators—who have promised to implement European drug guidelines even if the UK crashes out of Europe without a deal—will be excluded from Europe’s centralized IT portal for clinical trials and Europe’s single assessment model.

Pfizer has said that Brexit may cost the company up to $100 million because of disrupted trials and the need to stockpile supplies.