New Single-Dose, Intranasal COVID-19 Vaccine May Prevent Transmission, Disease

Pharmacy Times® interviewed Sarah Browne, MD, senior director of vaccine development at Altimmune, on the commencement of enrollment for a phase 1 clinical trial of AdCOVID, a single-dose, intranasal, adenovirus vector COVID-19 vaccine.

During the discussion, Browne explained that so far, all of the authorized vaccines are injected by a needle into the muscle, making the immune response a systemic immune response. For this reason, the AdCOVID vaccine is unique in that it’s administered as a spray into the nose, allowing the vaccine to be introduced to the nasal mucosa, creating a mucosal immune response in the body.

“The reason that this is important is because if you think about respiratory viral infections, like SARS-CoV-2 or influenza for example, they infect through the nose and get into the respiratory tract. So, there's really a special kind of immunity called mucosal immunity, which is generated at that site of infection,” Browne said. “So, by introducing the vaccine to the nasal mucosa via the intranasal root, you generate that special immunity to block the infection where it enters and potentially to also prevent it from exiting so that you avoid transmission.”

Since clinical trials are in the first human study, Browne explained that the majority of the data will be available in the spring, driving subsequent studies into the safety and immunogenicity.

“Moving into the summer and the fall, we'll be getting into advanced development. We're optimistic we could apply for an emergency use authorization or potentially an approval in early 2022,” Browne said.

Browne also noted that there are specific advantages to this vaccine being needle-free that will impact distribution and administration prospects.

“I think the needle-free aspect minimizes the need for health care providers to administer the vaccine, so you could really imagine just broad scale up in vaccination programs in community-based outreach that doesn't require that cold chain,” Browne said. “So, you could go to regions that don't have the same sort of take technological capability and give the vaccine broadly.”