Benzinga | Apr 1, 2021 07:04AM EDT

Altimmune Reports Data From Its Phase 1b Clinical Trial Of NasoShield

Altimmune, Inc. (NASDAQ:ALT), a clinical-stage biopharmaceutical company, reported clinical data today on its NasoShield intranasal anthrax vaccine candidate. The Phase 1b trial evaluated the safety and immunogenicity of one and two-dose regimens of NasoShield in healthy volunteers. The clinical trial was conducted with support from the Biomedical Advanced Research and Development Authority (BARDA).



The trial enrolled 42 healthy subjects who received intranasally administered NasoShield or saline placebo and were then monitored for 6 months post-dosing. The primary endpoint was the safety and tolerability of NasoShield. The primary immunogenicity readouts included the serum binding antibody to protective antigen and anthrax toxin blocking antibody responses at 28- and 56-days post-dose administration. Stimulation of the mucosal IgA immune response in the nasal cavity was also assessed.

The clinical data from the Phase 1b trial showed that:

* Serum binding antibody responses to the protective antigen of Bacillus anthracis, the bacterium and causative agent of anthrax, were significantly greater than in the placebo arm.

* Antibody responses blocking anthrax toxin were blunted compared to protective antigen antibody responses and were low compared to prior studies conducted with BioThrax(r), the only approved anthrax vaccine.

* Notably, as with Altimmune's other intranasally administered replication-deficient adenovirus vaccines, nasal mucosal IgA responses specific for protective antigen were observed in up to 80% of subjects post-vaccination.

* The safety and tolerability of NasoShield was excellent and comparable to intranasal saline placebo in both the number and characteristics of adverse or reactogenicity events, consistent with other clinical trials of Altimmune's intranasal vaccine candidates.

The NasoShield program is funded through a contract (HHSO100201600008C) with BARDA which, if all options are exercised, is expected to provide funding through the end of Phase 2 development. The Company plans to conduct a comprehensive review of the data with BARDA to determine the path for continued development of the program.