This 1 Factor May Limit the Reach of Pfizer's Coronavirus Vaccine

Investors -- and the rest of the world -- recently cheered when Pfizer (PFE -3.85%) released positive interim efficacy data from the phase 3 study of its investigational coronavirus vaccine. The big pharma company and its German biotech partner, BioNTech (BNTX -1.57%), said that their candidate was more than 90% effective in preventing infection.

Last week's report pushed Pfizer just ahead of rival Moderna (MRNA -2.45%). The two have been neck and neck from a timeline and data perspective since both launched phase 3 studies on July 27. But just yesterday, Moderna released interim data that showed its candidate is almost 95% effective at preventing infection. In an increasingly tight race, there is one element that may hold Pfizer back -- even if it crosses the finish line and wins an Emergency Use Authorization (EUA) first. And it has to do with something very basic: temperature.

Image source: Getty Images.

Transportation with dry ice

Pfizer's vaccine must be stored at negative 94 degrees Fahrenheit. Most vaccines can be kept at normal refrigerator temperatures of 35 degrees Fahrenheit to 46 degrees Fahrenheit. A few require freezers, with negative 58 degrees Fahrenheit being the lowest temperature. These temperatures make it easy enough to transport the vaccines and store them in medical offices and pharmacies. Those locations, however, usually don't have the equipment needed to store a vaccine at ultra-low temperatures.

In a statement made to FiercePharma back in August, Pfizer said its vaccine candidate can be stored at refrigerator temperatures for only two days. With regards to transportation, it plans to pack doses in special containers that are kept cold with dry ice. But what happens once the doses arrive at their destination? If the medical setting doesn't have freezers to store vaccine at the correct temperature, vaccinations would have to be administered within 48 hours.

Otherwise, only hospitals or clinics with the right infrastructure could offer the vaccine to patients. This implies vaccinations in specific locations only. Sutter Health, a hospital operator in Northern California, has already invested $100,000 in freezers to store the vaccine, according to the local ABC affiliate. Some of the freezers are portable, so vaccinations could take place in various locations. Even if other hospital operators throughout the country follow Sutter's lead, it's clear some small towns, medical offices, and pharmacies will be left out.

The challenge extends beyond the U.S. Bringing Pfizer's vaccine to countries with poor infrastructure seems unlikely at this point. Even if Pfizer manages the transport and delivery, most medical facilities don't have the equipment to store the vaccine or the funds to buy the necessary freezers.

A look at rivals

How do Pfizer's rivals compare? Moderna's investigational vaccine is similar in terms of technology. Like Pfizer, it is based on messenger RNA (mRNA) technology. Both vaccines use mRNA to instruct the body to make a protein from the virus. Then the immune system creates antibodies to target that protein. But Moderna's vaccine candidate can be stored at much warmer temperatures -- negative 4 degrees Fahrenheit. That puts it in the temperature range of other commercialized vaccines, and it makes transport and storage of this vaccine easier than Pfizer's.

Novavax (NVAX -4.82%) is farther behind in the race. The biotech company started its phase 3 trial in September and expects initial data in the early part of the first quarter. But down the road it has a logistical advantage. Its vaccine must be stored at 35 degrees to 46 degrees Fahrenheit. So, it can be stored in something as basic as a home refrigerator. Of course, this means Novavax's potential product could be more easily distributed and stored than those of Pfizer and Moderna.

What does this mean for Pfizer?

This doesn't mean that Pfizer's vaccine is out of the race. But it does suggest that its market potential could be more limited than that of Novavax or even Moderna, unless countries and medical facilities are willing and able to spend a lot -- and quickly -- on temperature infrastructure. As we saw with Sutter Health in California, some will do this. But it's unlikely the majority of hospital systems and countries will choose to spend, especially if other vaccines are available.

While Pfizer and BioNTech's vaccine candidate is incredibly promising in terms of its efficacy and safety profile, its temperature requirements may prevent it from becoming the market leader -- even if it wins the coronavirus vaccine race.