Novavax (NASDAQ:NVAX) shares started off in June around $150 a share. A few weeks later, those same shares are now worth $200. Why are the bulls sending this biotech stock higher? 

In this clip from Fool Live, healthcare and cannabis bureau chief Corinne Cardina and Fool.com writer Taylor Carmichael discuss the recent rise of Novavax stock. This segment was recorded on June 18.

Corinne Cardina: Let's start with Novavax. Between the three authorized vaccines in the United States, according to the CDC, about 44% of adults are fully vaccinated in the US. But we aren't necessarily done seeing new vaccines hit the market. Taylor, what did we hear from Novavax this week and what has been the market reaction?

Taylor Carmichael: Well, Novavax has had two big things that have happened over the last couple of weeks. The first thing that happened, the Biden administration released its hold on the raw materials that companies need to manufacture vaccines. The Biden administration had put a hold on it to keep those materials in the United States, which really hurt Novavax because their manufacturing is mostly abroad. They were manufacturing a billion doses of vaccine in India. That was big news, when the Biden administration finally released that hold, and it's allowed the Serum Institute of India to start ramping up their production. That was a huge boon for the stock, because the delays in Novavax's production had brought the stock, it was over $300 a share when it had positive phase 3 data and dropped all the way down to $120, somewhere in there. After that news came out, it jumped back up to about $200 a share. That was really good news. The other good news that happened is Novavax has positive phase 3 data from their U.S. trial. This is very similar to their phase 3 trial that they did in the U.K.. It's basically the same data, but it just reaffirms that this is great vaccine, that this is as good as the Moderna vaccine, as good the Pfizer vaccine.

They had 90% overall efficacy. One of the major differences like in their first phase, phase 3 trial, they had 96% efficacy against the original strain of COVID-19. All three of these biotech companies have created a vaccine for the original strain of COVID-19 last year. But in Novavax's case we're seeing data also against the mutating strains. In England, they had 96% effectiveness against the original strain and 89% effectiveness overall against the U.K. variant and other whatever variants have been around. This new trial, I believe it's 30,000 people in the United States and Mexico, they had 90% effectiveness overall. We haven't seen a breakdown between the original strain and the variants, but it's probably about the same as the U.K. study which had 89% effectiveness overall. Novavax has reported that almost all the people that got COVID after being vaccinated got one of the variants. These original vaccines aren't as protective against the variants as they are against the original strain of COVID-19. The market liked it. It wasn't a great jump, moved a little bit. I think the market basically was expecting positive phase 3 data for Novavax because they've already had a phase 3 trial. This is the second phase 3 trial. But they are really close to getting their emergency use authorization. The company thinks it might happen this month, but it's probably going to happen in the third quarter in July.

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