What happened

Moderna (MRNA 0.42%), considered by some to be the leader of the pack of coronavirus stocks at the moment, fell by 3.9% Tuesday on what was generally an up day for the broader stock market.

The most likely reason for this is the pronouncement of a Chinese pharmaceutical company, Sinopharm, which on Tuesday set a price range for its two COVID-19 vaccine candidates. 

A syringe being filled with a vaccine from a vial.

Image source: Getty Images.

So what

Like Sinopharm, Moderna is in late-stage testing of a vaccine candidate, the quite promising mRNA-1273. Moderna investors might have been spooked by the Chinese company's announcement of a price range, as it could imply that one or both of Sinopharm's candidates will soon be ready for regulatory review.

Probably almost immediately after that -- given the vast need for a vaccine -- it would be made available for public consumption.

Sinopharm's chairman, Liu Jingzhen, told China's Guangming Daily that his company's vaccines would cost less than the equivalent $145 for two doses, if either or both receive regulatory approval. Liu didn't specify whether he meant the list price or out-of-pocket-cost. 

Now what

That price is well above Moderna's stated "budget" range for mRNA-1273 of $32 to $37 per dose, and it's also higher than other Western developers' pricing targets. But first-mover advantage is going to be significant with coronavirus/COVID-19 vaccines, and a relatively small biotech like Moderna could face a serious challenge in trying to compete as a runner-up.