ToKYO - VLP Therapeutics Japan has begun a clinical trial of a new coronavirus vaccine which would require a far smaller dose than those of Pfizer and Moderna and could dramatically shorten production times, the company said on Monday.
The company, a subsidiary of a Japanese drug startup founded by U.S. researchers has developed the vaccine in partnership with six national research institutes, including Oita University, Hokkaido University and the National Center for Global Health and Medicine.
The vaccine is a messenger RNA style shot, similar to the ones of Pfizer and Moderna, but comes with an RNA polymerase that allows faster replication of RNA, says the company. It produces only a small part of the virus's spike protein - the spike's receptor binding domain - meaning that printing it requires less material.
The VLP vaccine, using such'replicon' RNA, would require only one-tenth or one hundredth of dosage of conventional messenger RNA vaccines, according to Wataru Akahata, CEO of VLP Therapeutics Japan.
Two British companies and a Canadian and a United States company are also developing COVID vaccines using similar technology.
The technology has not been pursued by big drug companies. Vaccines that target only the virus's receptor binding domain, rather than the entire spike protein, have been less successful at generating an immune response. The replicon RNA is also longer than a standard messenger RNA and therefore more difficult to produce. VLP Therapeutics Japan has come up with a way to compensate such shortcomings, Akahata says.
VLP has partnered with Fujifilm Toyama Chemical to mass produce the replicon RNA vaccine and aims to make up to 50 million doses a year. The company hopes to begin Phase 2 and Phase 3 clinical trials in the spring and file for approval by the end of 2022.
In Japan three quarters of the population has already been vaccinated for COVID-19 at least once. VLP envisages that its vaccine would be used for booster shots, as well as to export to countries where vaccines remain in short supply.