• Text in Japanese

Photo: Intradermal administration with the pyro-drive jet injector　

Main points

• A Physician-initiated clinical trial (Phase 1/2a) for a new DNA vaccine^*1 against the SARS-CoV-2 virus.
• A new gas-type, needleless injection system for intradermal injections^*2 of small amounts of DNA vaccine.
• More people who can receive the vaccine.

The laboratories of Professors Hironori Nakagami and Kunihiko Yamashita of the Osaka University Graduate School of Medicine have developed a needless pyro-drive jet injector^*3  to deliver vaccines. The power of the injection penetrates the skin to deliver the vaccine intradermally and was shown to be highly efficient in animal experiments.

The new device was shown to deliver more effective vaccine at smaller doses for the SARS-CoV-2 virus, the cause of the current coronavirus pandemic, than standard intramuscular injections in rats. Based on these animal experiments, on November 25, a clinical trial for the pyro-drive jet injector to deliver a DNA vaccine against the virus began at Osaka University Hospital under the supervision of Professor Kazunori Tomono.

The researchers have published details about their device in AAPS PharmSciTech (https://link.springer.com/article/10.1208/s12249-019-1564-z).

Background

DNA and RNA vaccines are relatively new forms of vaccines that can be rapidly developed for pandemics. One major challenge is their effective delivery. Osaka University researchers have therefore been investigating new devices and drug delivery systems for this purpose.

Summary of the clinical trial

DNA vaccines for the SARS-CoV-2 virus are being developed, but they require intramuscular injections for the delivery. In the Osaka University research, the pyro-drive jet injector uses intradermal gas propulsion, which is expected to lower the amount of vaccine needed to one-fifth or even one-tenth that needed for intramuscular injections. In the current trial, both the efficacy and safety of the intradermal delivery will be evaluated.

Participants: Adults 20-75 years old

Groups: 10 patients will receive a low dose vaccine and 10 patients a high dose vaccine

Date: November 25-December 3, 2020

Principle Investigator: Professor Kazunori Tomono, Laboratory of Infection Control and Prevention, Osaka University Graduate School of Medicine

Significance of the research

The coronavirus pandemic has caused aggressive international research on a vaccine. Typically, vaccines are delivered intramuscularly or subcutaneously, but subcutaneous delivery is thought to require a smaller dose, since that region has more immune cells that can react to the virus. With the amount of coronavirus vaccine available limited, the pyro-drive jet injector developed by Osaka University researchers would enable more people to be vaccinated against the virus.

Details of the AAPS PharmSci Tech research paper

Title: Stable Immune Response Induced by Intradermal DNA Vaccination by a Novel Needleless Pyro-Drive Jet Injector.

Authors: Chang C, Sun J¹, Hayashi H², Suzuki A³, Sakaguchi Y³, Miyazaki H³, Nishikawa T¹, Nakagami H², Yamashita K^1,3, Kaneda Y¹

Affiliations: 1) Department of Device Application for Molecular Therapeutics, Osaka University Graduate School of Medicine. 2) Department of Health Development and Medicine, Osaka University Graduate School of Medicine. 3) Medical Device Division, Daicel Corporation.

Funding: Japan Agency for Medical Research and Development (AMED).

Project name: Vaccine development for new coronavirus disease (COVID-19)

Research program name: Development of vaccine targeting new coronavirus disease (COVID-19)

Participating organizations: AnGes, Inc. and the Research Institute for Microbial Diseases, Osaka University

Notes

*1 DNA Vaccine: A vaccine where genetic information of an antigen related to the infecting virus is put inside a vector, which is delivered into the body. The antigen then reproduces, eliciting the production of antibodies that protect the body from future infection.

*2 Intradermal injection: Drug delivery to the area between the epidermis and dermis of the skin. This region has many immune cells, resulting in a strong reaction to even a small dose.

*3 Needleless device: A device that delivers a drug into the skin by a rapid injection. In the present research, the device uses a small explosion to deliver the DNA vaccine.