The Financial Times reports Pfizer saw a price hike of over 25%, while Moderna was up roughly 10% as demand for the vaccines increases because of the wildfire-like spread of the Delta variant.

The deals cover 2.1 billion doses through 2023 and follow Phase III trial data that shows their mRNA vaccines had higher efficacy rates than those by AstraZeneca and Johnson & Johnson.

Pfizer will now get about $23.16 per jab from the EU, compared with the $18.41 it previously received. Moderna shots are jumping from $22.60 to $25.50. (That would have been even higher, the FT reports, but the order was increased, bringing the price down.)

Last week, Pfizer raised its global sales forecast for its COVID vaccine from $26 billion in 2021 to $33.5 billion.

So far, there’s no sign that either company hopes to raise prices in the next round of negotiations with U.S. government officials. Pfizer has said that it is providing its vaccine at a discount to poorer countries.

In either case, both the Pfizer and Moderna vaccines are still being provided free of charge for citizens of the U.S. and EU—and will continue to be for the foreseeable future.

The mRNA-based vaccines from Pfizer and Moderna may not be quite as effective at reducing transmission of the Delta variant, but available data from multiple nations finds that the two vaccines are 96% effective in preventing COVID hospitalizations and deaths from Delta variant infections.