The approval of Nefecon in China is a significant milestone for Calliditas, as it opens up a large market for the treatment of IgA nephropathy. This is likely to be viewed positively by investors, as it represents progress in the company's pipeline and potential for revenue growth. The partnership with Everest Medicines is crucial for distribution and market penetration in China, which is a key factor in the potential increase in Calliditas' stock value in the short term.