Novavax (NASDAQ:NVAX) was up 9.1% in early afternoon trading Thursday after it announced that it had signed a development and supply agreement with SK Bioscience, a subsidiary of SK Group, to produce the antigen component of its COVID-19 vaccine candidate. In addition, both companies signed a letter of intent to make Novavax's vaccine available in South Korea.

Word of this deal comes on the heels of major international supply agreements Novavax signed last week. On Aug. 6, it inked a license agreement with the Serum Institute of India to provide a billion doses of Novavax's COVID-19 vaccine throughout India and other low- and middle-income countries. On Aug. 7, Novavax signed a license agreement with Takeda Pharmaceutical (NYSE:TAK) to provide 250 million doses of the vaccine in Japan.  

bottles of COVID-19 vaccine

Image source: Getty Images

While the size of the SK Bioscience deal was not disclosed, Novavax has already lined up enough manufacturing capacity to produce almost 3 billion doses of its vaccine in 2021. By contrast, consider the new COVID-19 vaccine candidate of Moscow-based Binnopharm, which Russian regulators approved for use this week, despite the fact that it has not yet been tested in a phase 3 clinical trial. Binnopharm has said that it can only produce 1.5 million doses of its vaccine per year.

The announcement that the Russian vaccine candidate had been approved for use in its home market sent COVID-19 vaccine stocks tumbling this week. Novavax dropped from a high of $181 a share on Monday to $112 a share on Wednesday. That sell-off was very likely an overreaction, though, given the limited manufacturing capacity available for producing that vaccine, and the lack of trial data that would show whether or not it works well enough to justify its approval.

For the year, Novavax stock remains up by more than 3,200%.