Novavax (NVAX -0.43%) has brought investors extreme gains and extreme losses in just a few years. In 2020, the biotech company soared more than 2,700%. That was as investors bet on its coronavirus vaccine program. But Novavax fell behind. And it launched its vaccine a year after those of rivals.

Since, Novavax shares have made their way progressively back down to earth. And this year, they're heading for a 92% loss. Meanwhile, due to a late commercial start, Novavax's vaccine sales have disappointed. Now the question is: Is there any hope for this embattled stock? Let's find out.

An alternative to mRNA vaccines

First, a bit of background on Novavax's vaccine story. The company developed a protein subunit vaccine, one that works a lot like traditional vaccines. So, it offers an option for individuals who hesitated to go for the new technology of mRNA proposed by rival vaccine makers Pfizer and Moderna.

But, by the time Novavax's vaccine entered the market, most people who wanted vaccination already had gotten a jab. That left a limited audience for the Novavax product. Still, Novavax generated more than $620 million in vaccine sales in the most recent quarter.

And even though it's lowered annual sales forecasts, it still expects about $2 billion in total revenue for the year. That's significant considering it had zero product revenue before the vaccine's launch.

Novavax is likely to continue generating vaccine sales next year. Many countries, including the U.S., have authorized Novavax's vaccine for use as a booster in adults. This revenue could become recurrent. That's because the coronavirus booster market may follow in the footsteps of the flu vaccine market. People may go for covid boosters every year.

That said, Novavax may struggle to carve out much of a share facing market giants Pfizer and Moderna.

A drop in vaccine deliveries

And recent news hasn't been bright. Novavax announced a cut to vaccine deliveries to the U.K. It now will deliver 7.5 million doses instead of 15 million. This means Novavax must repay about $112 million from the U.K.'s upfront payment to the company.

Novavax also recently ended its purchase agreement with Gavi, the Vaccine Alliance. Gavi didn't purchase the vaccine doses covered by the contract, the company said. But a Gavi spokesperson told Reuters Novavax wouldn't be able to meet its commitment to actually produce the doses this year.

All of this makes Novavax's near term look very complicated. I recently wrote that the company's long-term prospects still look good. And I maintain that view.

Like Moderna, Novavax is working on a combined coronavirus/flu vaccine. But Novavax's program is more advanced. If it's successful, this could be a big product. And Novavax could carve out a significant share in the future vaccine market. This means Novavax shareholders may want to hold on and wait for better days.

Should you buy the shares?

But I've become a little more pessimistic on Novavax's near-term story considering the recent supply agreement news.

I wouldn't recommend buying Novavax stock today -- unless you're a very aggressive investor and want to start building a small position. Why? It doesn't look as if there is any near-term news to boost this stock. And any new disappointments could seriously drag it down. So, it's best to wait until the company's situation stabilizes.

But there's still hope for Novavax over the long term. That's why it's a great idea to add Novavax to your watch list now. Then look for two things: its vaccine sales as we shift to a post-pandemic situation and the progress of its combined vaccine candidate. If and when the company reports positive news in these areas, Novavax could be a great biotech buy once again.