What happened 

Cruise ship stocks rallied on Friday, following the blockbuster news of a game-changing new COVID-19 treatment.

As of 3:45 p.m. EDT, shares of Royal Caribbean (NYSE:RCL), Carnival (NYSE:CCL) (NYSE:CUK), and Norwegian Cruise Line Holdings (NYSE:NCLH) were up 9%, 8%, and 8%, respectively. 

So what

An interim analysis of a phase 2/3 clinical trial showed that Pfizer's (NYSE:PFE) experimental antiviral pill reduced the risk of hospitalization or death by 89% in adults with COVID. The news gave health officials hope that the pandemic could soon come to an end. 

"By Jan. 4, this pandemic may well be over, at least as it relates to the United States, after we get through this delta wave of infection," Dr. Scott Gottlieb, Pfizer board member and former commissioner of the Food and Drug Administration, said in an interview on CNBC. 

A cruise ship is at port near an island.

Cruise ship stocks rose sharply on Friday. Image source: Getty Images.

Investors took the news as a sign that the cruise industry's recovery could gain steam, and they bid up the shares of the major cruise operators in kind.

Now what

COVID took a brutal toll on Carnival, Royal Caribbean, and Norwegian Cruise Line during the early stages of the pandemic. With their ships stuck in port due to coronavirus-related sailing restrictions, they quickly racked up massive losses. This in turn forced these cruise operators to take on debt and dilute shareholders with stock sales.

But if Pfizer's new drug can help reduce the risks of COVID, passengers could return in droves. That could help cruise lines begin to recoup their losses -- and perhaps place them on a course to sustained profitability once again.

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