Pfizer’s (PFE) coronavirus vaccine candidate is currently being tested on humans, using multiple options and dosing levels, and potentially accelerating the timeline for when it can be used.

It was created using a new technology, which means a new supply chain the company must navigate before its treatment can be deployed, a top executive told Yahoo Finance on Wednesday.

For one of the world’s largest vaccine producers, being the first major U.S. player to reach clinical trials was met with increased optimism about the ability to curb an outbreak that’s infected nearly 4 million around the world.

Pfizer is using messenger RNA — an approach similar to one in use by Moderna (MRNA), which allowed the company to reach clinical trials in record time in March. Several companies, including drug giant Johnson & Johnson (JNJ) are engaged in a race to create a COVID-19 cure.

The smaller Moderna has announced a partnership that will allow it to ramp up production, and bring up to 1 billion doses to market when ready. Meanwhile, Pfizer’s bigger reach, and its position in the industry as a large vaccine producer, has allowed the company to pivot its own resources to meet expected demand.

Using the new mRNA technology makes the task “more complicated,” Philip Dormitzer, Pfizer’s chief scientific officer of viral vaccines, told Yahoo Finance — but a challenge the pharma giant expects to meet using innovation and know-how.

“The elements of the technology, as well as adapting the technology to the new disease, are the challenge,” he said, adding that regulators will be extra wary to ensure it is fit for public use.

“Not only do the regulators want to make sure the vaccine is safe, they want to make sure the underlying technology is safe,” Dormitzer.

Back in August 2018, Pfizer partnered with BioNTech to produce a flu vaccine based on the new technology. So when the sequence of the new coronavirus was released by China in January, the companies plugged it in and shifted their focus.

Usually, vaccine development involves using a piece of the virus, or a weakened version of the virus. With mRNA, the immunization happens with a set of instructions encased in a lipid — an oily or waxy fat bubble — delivery system into the person’s muscle.

Dormitzer said that unlike the 2009 flu pandemic, the coronavirus outbreak has no current vaccine to use in developing a variant, so the timeline is unknown for the untested technology.

BioNTech already has production capability in Germany, and Pfizer is working on its manufacturing capabilities in the U.S. The two-part production requires a specialized encasing.

“It’s really (both) an RNA and lipid vaccine, so you’ve got to make every piece of it. So the lipid piece turns out to be one of the most challenging pieces,” Dormitzer said.

But, he added, at-large, its an efficient process, even though the lipids are specialized.

"We are innovating our virtual technology transfer process at speed and a completely virtual transfer will be a first for Pfizer, but we are confident in our abilities to successfully complete and implement the technology,” he said.

But in order to meet the demand of hundreds of millions of doses, even with a robust manufacturing system, “there’s no getting around having the infrastructure to make many, many vials, accessing lots of syringes — all that part remains a challenge, even as we make the upstream part much more efficient,” Dormitzer added.

Anjalee Khemlani is a reporter at Yahoo Finance. Follow her on Twitter: @AnjKhem

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