Nasal spray may offer room temperature distribution that could reduce logistical challenges for healthcare systems and providers

Intranasal administration targets the virus at its point of entry and in a preclinical study induced local nasal mucosal immunity believed to be critical for preventing further viral transmission

GAITHERSBURG, MD, USA I February 25, 2021 I Altimmune, Inc. (Nasdaq: ALT), a clinical-stage biopharmaceutical company, today announced that it has commenced enrollment in a Phase 1 clinical trial of AdCOVID, a single-dose intranasal COVID-19 vaccine candidate. AdCOVID is an adenovirus-vector vaccine designed to stimulate a broad immune response including both systemic immunity (neutralizing antibody) and local immunity (mucosal IgA and resident memory T cells) in the nasal cavity and respiratory tract.

The Phase 1 clinical trial will evaluate the safety and immunogenicity of AdCOVID in up to 180 healthy adult volunteers between the ages of 18 and 55. Subjects will receive AdCOVID at one of three dose levels administered as a nasal spray. In addition to the primary study endpoint of safety and tolerability, the immunogenicity of AdCOVID will be evaluated by serum IgG binding and neutralizing antibody titers, mucosal IgA antibody from nasal samples, and T cell responses. Altimmune anticipates having a full data readout from this Phase 1 study in Q2 2021.

“The commencement of our Phase 1 clinical trial of AdCOVID is an important milestone for our company and the global healthcare community in our fight against the SARS-CoV-2 virus,” said Dr. Scott Harris, Chief Medical Officer of Altimmune. “We believe that our expertise in intranasal vaccine development will help us bring to market a novel intranasal COVID-19 vaccine with important attributes that could potentially help prevent further transmission of the virus. Delivering vaccine directly to the nasal cavity may stimulate a specialized type of immunity called ‘mucosal immunity,’ which has been shown in a preclinical study to provide sterilizing immunity, that is, complete clearance of the virus from the respiratory tract. As the rise of new variants of the SARS-CoV-2 virus is particularly troubling, to stop mutations of the virus we must stop replication and transmission, and we believe AdCOVID could play an essential role in this endeavor.”

While traditional vaccines delivered by an intramuscular injection can stimulate systemic immunity in the blood, they have not been shown to induce mucosal immunity in the nasal cavity, which may be critical for blocking transmission of the virus. AdCOVID is designed to deliver vaccine directly to the site of viral entry and replication to stimulate mucosal and cellular immunity in the nasal cavity and respiratory tract – potentially offering a first line of defense against the SARS-CoV-2 virus. The ability to stimulate mucosal and resident T cell immunity in the respiratory tract would be a key differentiator for AdCOVID and may play a critical role in blocking transmission of the SARS-CoV-2 virus.

“While the roll out of currently available vaccines is an important first step in our efforts to slow the pandemic, there remains a critical need for vaccines that provide mucosal immunity,” said Scot Roberts, Ph.D., Chief Scientific Officer of Altimmune. “As pioneers in intranasal vaccine development, we believe AdCOVID has the potential for many advantages over currently available vaccines, including, intranasal dosing and ease of distribution and storage, if the product is shown to have extended stability at room temperature, in addition to the potential ability to block transmission of the virus.”

About AdCOVID

AdCOVID is a single-dose intranasal vaccine candidate for COVID-19. It is designed to stimulate a broad immune response including both systemic immunity (neutralizing antibody) and local immunity (mucosal IgA, resident memory T cells) in the nasal cavity and respiratory tract.

In published preclinical studies conducted in collaboration with the University of Alabama at Birmingham, potent serum neutralizing antibody responses, T cell responses, and a robust induction in mucosal immunity were observed in mice following a single intranasal dose of AdCOVID. Mucosal immunity was characterized by IgA antibody and resident memory T cell responses in the respiratory tract, both of which are believed to be important in fighting infection, and importantly, transmission.

Based on data from Altimmune’s other intranasal platform vaccine candidates, AdCOVID is expected to have extended stability at room temperature that would allow for cold chain-free shipment of the vaccine. If demonstrated, AdCOVID could be stored in the common refrigerators found in community-based doctors’ offices and pharmacies for two years or more. The Company believes that these simple and convenient handling requirements, together with the potential ability to block SARS-CoV-2 transmission, could position AdCOVID as a leading intranasal COVID-19 vaccine.

About Altimmune

Altimmune is a clinical stage biopharmaceutical company focused on developing intranasal vaccines, immune modulating therapies and treatments for liver disease. Our diverse pipeline includes proprietary intranasal vaccines for COVID-19 (AdCOVID™), anthrax (NasoShield™) and influenza (NasoVAX™); an intranasal immune modulating therapeutic for COVID-19 (T-COVID™); and next generation peptide therapeutics for NASH (ALT-801) and chronic hepatitis B (HepTcell™). For more information on Altimmune, please visit www.altimmune.com.

SOURCE: Altimmune