Four COVID-19 vaccines have started Phase 3 human clinical trials in the United States, and a fifth is expected to be announced this month by Novavax. Two coronavirus vaccines are in development by Pfizer at the Michigan Center for Medical Research in Rochester and by Moderna at the Henry Ford Health System in Detroit.
The Johnson & Johnson / Janssen and AstraZeneca clinical trials, which were ongoing at the University of Michigan, have been suspended in the United States for safety reasons. The AstraZeneca trial was suspended for more than a month after two people fell ill. The J&J lawsuit was suspended last week when a person fell with an unexplained illness.
Still, the CEOs of Pfizer and Moderna say their vaccines could be mass-produced on a limited scale by the end of the year. Other drugmakers say their vaccines show promise, but some experts estimate mass production is over six months away.
Pfizer’s mRNA-based vaccine now requires ultra-cold storage of -70 degrees Celsius, making administration by physician offices, clinics and retail pharmacies virtually impossible.
Moderna’s vaccine, which also uses the new mRNA-based technology, currently requires a temperature of -20 Celsius, which allows for greater storage flexibility. The company also said its vaccine can be stored in normal vaccine refrigerators for up to seven days.
Novavax said its vaccine can be stored between 2 and 8 degrees Celsius in an unfrozen liquid formulation that can be stored in a standard vaccine refrigerator. The Maryland-based drug maker takes a more traditional approach to vaccine development. It uses viral proteins rather than an mRNA genetic code approach to train the body against coronavirus infection.
Merck and Sanofi, two veteran vaccine makers who jumped into the vaccine race this summer, are said to be about to begin Phase 3 trials.
Once one or more vaccines are approved by the FDA, possibly through emergency use authorization, companies will begin mass production.
Chaz Calitri, Pfizer’s vice president of operations for sterile injections, said the drug company had packed the vaccine doses filled to Kalamazoo for its Phase 3 trial since the start of this year. More than 300 workers have been hired for the coronavirus vaccination effort, he said.
“If the vaccine is successful and we launch it, we plan to hire up to 700 people” in Kalamazoo, Calitri said. The plant currently has around 3,000 employees.
Pfizer’s COVID-19 clinical trials have been expanded to more than 44,000 people, including adding more minorities and adolescents and young people as young as 12, officials said.
“What we’re going to do is have the vials (of vaccine) wrapped in little pizza-shaped boxes and placed in a container wrapped in dry ice. It will be like a container in a container that will have a tracker. , “or a sensor that will monitor location and temperatures, Calitri said.
Doctors asked Pfizer if the company would develop a way to store the vaccines at temperatures above -70 degrees Celsius. Pfizer said it was working on a plan to store its vaccines for up to 24 hours in the standard refrigerator.
“They are still testing to see if there can be less storage time and higher temperatures,” Calitri said.
Another question is whether the vaccines will be single-dose injections, like the proposed Johnson & Johnson / Janssen or Merck vaccines, or two-dose injections like Pfizer, Moderna and others. Two doses will require careful monitoring of people and appointment reminders, like the shingles vaccine.
Experts are also concerned that the hundreds of millions of vaccine doses will also require an increase in the production of pharmaceutical grade syringes and glass vials needed to transport and administer the vaccines. Operation Warp Speed awarded large contracts to companies to build up inventory.
Julie Swann, professor of industrial and systems engineering and department head at North Carolina State University in Raleigh, said there were a number of logistical challenges in the transport and distribution of COVID-19 vaccines, in particularly the Pfizer vaccine which appears to be the most advanced towards approval.
“It’s not like the vaccines you know, the seasonal flu shot you might get at a target or CVS, or at your doctor’s office. It’s different from that,” said Swann, who is an expert in the vaccine supply chain. “It has a much greater perishability and needs to be stored at a much cooler temperature. Dry ice will also need to be provided throughout the supply chain.”
Pfizer vaccine, for example, must be shipped in containers with dry ice containing 975 doses.
“So you’re going to send this specialized 1,000-dose box to a hospital and you’re only allowed to open it once a day because it will be frozen and you will have to take out enough for these people,” Swann said.
Vaccines with lower doses per box, such as those from Moderna, which are expected to launch with orders of 100 doses, can be shipped to doctors’ offices, clinics and retail pharmacies, Swanson said.
“If this is the Pfizer vaccine, with the ultra-cold requirements, it is likely to be shipped directly from the drug company to the hospital or to a large clinic,” Swanson said.
CVS Health spokesperson Mike DeAngelis said its Minute Clinic sites are well placed to administer COVID-19 vaccines.
“We look forward to playing an important role in the vaccine distribution process, and our experience of delivering millions of flu shots each year helps inform our plans,” DeAngelis said in an email.
Most pharmacies and doctors’ offices have regular freezers and could only store vaccines at low temperatures for short periods.