Painless’ vaccine needle invented in Japan

The fear of a visit to the doctor for an injection will soon be a thing of the past thanks to a painless new vaccine delivery system that has been perfected in Japan.

Kanji Takada, a professor of pharmacokinetics – or the study of the absorption, distribution and fate of substances delivered to the human body – has developed a round vaccine “chip” measuring just 1.5 cm in diameter that contains as many as 300 micro needles. The device can deliver drugs to the body without breaking the dermis layer of skin.

By penetrating just 0.5 millimetres before the needles dissolve and administer the vaccine, the patient feels no discomfort and there is no bleeding, said Professor Takada, of Kyoto Pharmaceutical University.

“The patch can be used to deliver any type of vaccine and people are not frightened of having the injection because they feel nothing at all,” said Professor Takada.

It has taken Professor Takada six years to develop the new drug delivery system, with earlier efforts by other researchers to use microneedles made out of sugar failing because they degraded at temperatures above 100 degrees centigrade, he said.

Professor Takada replaced sugar with a water-soluble polymer that dissolves when pressed into the epidermis, the very outer layer of skin, releasing the vaccine to be absorbed into the circulatory system.

Each of the dozens of needles is a mere 0.5 mm long and 0.3 mm wide at the base and tests show that the efficiency of the vaccine is not adversely affected by the method of delivery.

Professor Takada’s new injection system could be available for use in hospitals in Japan within two years.