Thin silk fibroin films as a dried format for temperature stabilization of inactivated polio vaccine

Vaccine. 2020 Feb 11;38(7):1652-1660. doi: 10.1016/j.vaccine.2019.12.062. Epub 2020 Jan 17.

Abstract

Current inactivated polio vaccine (IPV) products are sensitive to both freezing and elevated temperatures and therefore must be shipped and stored between 2 °C and 8 °C, a requirement that imposes financial and logistical challenges for global distribution. As such, there is a critical need for a robust, thermally stable IPV to support global polio eradication and post-eradication immunization needs. Here, we present the development of air-dried thin films for temperature stabilization of IPV using the biomaterial silk fibroin. Thin-film product compositions were optimized for physical properties as well as poliovirus D-antigen recovery and were tested under accelerated and real-time stability storage conditions. Silk fibroin IPV films maintained 70% D-antigen potency after storage for nearly three years at room temperature, and greater than 50% potency for IPV-2 and IPV-3 serotypes at 45 °C for one year. The immunogenicity of silk fibroin IPV films after 2-week storage at 45 °C was assessed in Wistar rats and the stressed films generated equivalent neutralizing antibody responses to commercial vaccine for IPV-1 and IPV-2. However, the absence of IPV-3 responses warrants further investigation into the specificity of ELISA for intact IPV-3 D-antigen. By demonstrating immunogenicity post-storage, we offer the air-dried silk film format as a means to increase IPV vaccine access through innovative delivery systems such as microneedles.

Keywords: Fibroin; Poliovirus; Silk; Stabilization; Vaccine.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Antibodies, Neutralizing / blood
  • Antibodies, Viral / blood
  • Drug Storage
  • Fibroins / chemistry*
  • Immunogenicity, Vaccine*
  • Poliomyelitis / prevention & control
  • Poliovirus Vaccine, Inactivated / chemistry*
  • Poliovirus Vaccine, Inactivated / immunology*
  • Rats
  • Rats, Wistar
  • Temperature*

Substances

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Poliovirus Vaccine, Inactivated
  • Fibroins