Dry powder formulations of hyperimmune serum

Area of Science:

• Immunology
• Pharmaceutical Sciences
• Virology

Background:

• The COVID-19 pandemic highlighted the need for effective strategies against respiratory viruses beyond vaccination.
• Nasal delivery of protective agents targets the initial site of viral infection, offering a promising preventive measure.

Purpose of the Study:

• To formulate a stable, dry powder hyperimmune serum for nasal administration against SARS-CoV-2.
• To evaluate the aerodynamic properties and airway targeting of the formulated nasal powder.
• To assess the neutralizing capacity of the hyperimmune serum against SARS-CoV-2 variants.

Main Methods:

• Hyperimmune serum from SARS-CoV-2 vaccinated individuals was spray-dried with trehalose and mannitol.
• Immunoglobulin binding to Spike protein was confirmed via ELISA.
• Neutralization assays against SARS-CoV-2 pseudoviruses were performed.
• In vitro nasal cavity models and a Next Generation Impactor were used to assess powder aerosolization and distribution.

Main Results:

• Spray-dried hyperimmune serum retained binding and neutralizing activity against SARS-CoV-2.
• The powder formulation demonstrated inhalable properties, targeting both upper and lower airways.
• Trehalose as a bulking agent caused a slight reduction in neutralizing ability compared to mannitol.

Conclusions:

• Nasal delivery of hyperimmune serum powder is a feasible strategy for respiratory virus protection.
• This approach offers potential for rapid formulation and administration against emerging viral threats.
• The method provides broad coverage and timely neutralization of viral variants affecting the airways.