Research deal delivers RNAi drugs

According to Philips, compounds based on RNAi represent a promising new class of drugs for the targeted treatment of a number of diseases, including cancer and cardiovascular disease.

Currently, however, one of the greatest challenges in developing RNAi-based therapeutics is finding ways to deliver them to their target while keeping them fully active.

The joint research programme between Philips and US-based RXi will address this challenge by exploring, in preclinical studies, the possibility of using RXi’s sd-rxRNA (self-delivering rxRNA) in conjunction with Philips’ ultrasound technology to achieve the targeted delivery and monitoring of RNAi-based compounds in cells.

‘The development of ultrasound techniques that could non-invasively trigger the delivery of new drug formats such as RNAi therapeutics at a targeted location opens up exciting possibilities for advancing personalised medicine,’ said Henk van Houten, senior vice president of Philips Research and head of the healthcare research programme.

‘The most important technological challenges that need to be addressed in order to realise the promise of RNAi-based approaches to treating various human disorders are efficient and safe delivery of the RNAi compounds to the targeted organs, and uptake of these compounds by relevant cells,’ said Noah D Beerman, president and chief executive officer at RXi.

Delivering therapeutics

Diseases, as well as their potential cures, are associated with specific processes at a cellular and molecular level. RNAi technology is said to be a breakthrough in understanding how genes are turned on and off and represents a new approach to drug development. Therapeutics that exploit this breakthrough technology can potentially target the cause of specific diseases by silencing harmful genes and preventing disease-causing proteins from being produced.

To realise this potential, RNAi compounds must first be optimised in a way that confers them with the required drug properties and second, to enhance their delivery to cells that express these harmful genes.

RXi’s rxRNA molecules are chemically modified to provide them with properties such as stability in biological fluids, low stimulatory effect on the immune system and high target specificity.

Philips’ image-guided ultrasound-mediated drug-delivery platform reportedly offers researchers a unique approach to investigating the delivery of various therapeutic molecules across blood-vessel barriers and facilitating their uptake in cells.