VBI Vaccines (VBIV -9.86%) was a stock market star on Thursday, following some positive news items about its development of a coronavirus vacicine...or vaccines.

The company said it has chosen two vaccine candidates for further development. Both VBI-2901 and VBI-2902 have the potential to be one-dose vaccines, which is attention-grabbing as some of the more advanced candidates being developed by rivals require two doses.

Child getting a jab from a medical professional.

Image source: Getty Images.

The decision comes on the heels of three pre-clinical trials in which VBI's candidates were tested on mice. They induced antibodies that could neutralize the coronavirus after a single dose.

VBI will put both candidates through their paces in phase 1/2 human clinical studies. It hopes to start these around the end of this year.

"We are very encouraged by these results and remain deeply committed to addressing this devastating public health crisis," the company quoted its CEO Jeff Baxter as saying.

Following the news, on Thursday a pair of analysts tracking VBI stock raised their respective outlooks on the company. Oppenheimer's Leland Gershell lifted his price target by 60% to $8 per share, saying that the VBI could produce the best-in-class vaccine against the coronavirus.

His colleague Steven Seedhouse at Raymond James upgraded the stock to strong buy from outperform, bumping the price target up $1 to $9.

VBI said that it has signed an agreement with contract developer and manufacturer Therapure Biomanufacturing to provide its services for VBI-2901 and VBI-2902 in the phase 1/2 clinical trials. VBI specified neither the terms nor the cost of that deal.

Unsurprisingly, VBI's stock took off like a rocket on Thursday, closing 32% higher while the S&P 500 index gained marginally on the day.