What happened

Shares of BioNTech (NASDAQ:BNTX) rose nearly 30% today after the company announced it will soon begin clinical trials of coronavirus vaccine candidates in Germany. The biotech and its development partner, Pfizer (NYSE:PFE), were granted permission from the Paul-Ehrlich-Institut, Germany's medical regulatory body, to proceed with investigational studies. 

The clinical trial will be the first of a coronavirus vaccine candidate to begin in Germany, although BioNTech and Pfizer expect to soon begin trials in the United States and China, too. As of 10:51 a.m. EDT on Wednesday, the pharma stock had settled to a 13.1% gain.

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So what

The German clinical trial will actually test four unique vaccine candidates. BioNTech designed each to trigger the body's production of antibodies thought to protect against the SARS-CoV-2 virus, which appears to attach to certain cells in the human body using high-affinity spike proteins. 

Two of the vaccine candidates target a long genetic sequence of the spike protein found on the surface of SARS-CoV-2 particles, while the other two contain a shorter sequence targeting a specific section of the spike protein. 

The four coronavirus vaccine candidates are based on messenger RNA (mRNA) chemistry, similar to the technology platform of Moderna. The phase 1/2 trial will seek to find the optimal dose in healthy individuals. 

Now what

Today's news signals progress in humanity's race against the coronavirus pandemic, but there's still a long road ahead for BioNTech and Pfizer. It will take time to assess the safety and efficacy of the vaccine candidates. The human body and adaptive immune system can only produce antibodies so quickly. Meanwhile, it will be important to ensure that the vaccine candidates don't trigger antibody-dependent enhancement (ADE), which could make individuals more susceptible to severe infections. 

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