AstraZeneca stock rose early Thursday after the drugmaker beat fourth-quarter earnings views and delivered upbeat guidance.

In addition to the UK investment controversy, AstraZeneca is also dealing with legal challenges in China. The company confirmed that its Chinese business is under investigation for alleged unpaid import taxes on certain cancer drugs, including Imfinzi (durvalumab) and Imjudo (tremelimumab).

Investors were reassured after the drugmaker said a potential fine in China would have only a minor business impact.The company said it could face a charge of up to $4.5 million in the country over suspected unpaid import taxes for two cancer drugs.

Drugmaker AstraZeneca has warned it could face a fine in China over possible unpaid import taxes, as it revealed strong sales of cancer drugs helped drive revenues higher. At such a critical moment in US history, we need reporters on the ground. Your donation allows us to keep sending journalists to speak to both sides of the story.

AstraZeneca investors will look past another strong set of quarterly results on Thursday to focus on the main issue overhanging shares: an investigation of a top executive by authorities in China, one of its key markets.