Pfizer Inc. and BioNTech SE will raise COVID-19 vaccine deliveries to the European Union by 25 per cent this quarter, helping the bloc overcome delays to the shot from Johnson & Johnson.

The U.S. drugmaker and its partner will bring forward 50 million deliveries scheduled for the fourth quarter, adding to the 200 million doses already planned. The company provided about 66 million in the first three months of the year.

Faster deliveries could help offset the impact of delays to the J&J shot, which was paused while U.S. regulators review rare cases of blood clots to the brain. The possible side effects are similar to those seen with AstraZeneca Plc’s vaccine, which relies on the same approach.

Concern about Astra’s shot has already limited its usage: A number of EU countries have restricted it to certain age groups, and Denmark on Wednesday dropped it completely from its inoculation program.

European Commission President Ursula von der Leyen said the J&J news showed there are “many factors that can disrupt” schedules, but that the commission will press ahead to accelerate inoculations. EU countries have now administered 100 million shots, and 27 million people are fully vaccinated, she said.

The EU, grappling with a fresh wave of the pandemic, was counting on getting about 55 million J&J vaccines by the end of June. A prolonged delay would mark another setback for the 27-member bloc, which was finally starting to accelerate vaccinations after trailing far behind the U.S. and U.K.

While Pfizer’s new timetable will help, its shot takes two injections for full protection, compared with just one for J&J.

Von der Leyen also announced the EU was entering formal negotiations with Pfizer and BioNTech for as many as 1.8 billion additional vaccine doses through 2023.

The talks are part of the EU’s push to ensure citizens don’t face shortages of crucial shots in coming years, and to secure vaccines that will be effective if future virus variants are able to elude the current shots. The additional doses would mainly include booster shots and vaccines for children, EU officials have said.

The U.S. Food and Drug Administration said Tuesday it had made the recommendation to pause J&J “out of an abundance of caution.”