Isis Biopolymer Inc., a company developing a new generation of non-invasive drug delivery patches, has raised $3 million through an equity sale to existing investors.

The Providence, R.I.-based firm has developed the Isis Patch, a compact, wireless, active iontophoretic patch using a design that implements advances in microprocessors, thin film batteries, biopolymers and adhesives.

In a statement sent to MassDevice, CEO Emma Durand said the current round “clearly shows the confidence of the investment community in Isis Biopolymer and our innovative transdermal drug delivery and biosensor technology.”