in-PharmaTechnologist spoke with Tod Woolf, president and CEO at RXi, who explained the advantages of using its proprietary technology, self-delivering RNA (sdRNA).
sdRNA is taken up by cells without needing a delivery vehicle, which Woolf claims reduces costs, decreases the complexity of toxicology studies and allows for subcutaneous delivery.
Woolf added that RNA delivered using an encapsulation vehicle needs to be administered intravenously, which could require visiting a physician once a week, making the treatment significantly less convenient and potentially limiting its use to those with chronic ailments.
In addition in cell culture tests RXi has demonstrated that sdRNA is efficiently taken up by most cell types, although the pharmacology inside the human body will limit the organs it is effective against.
These include the liver and tumour sites but other areas, such as the eye, could be targeted with local injections to ensure sufficient concentrations of RNA reach the affected cells, according to Woolf.
Local administration is used by some of the RNA treatments in clinical trials but Woolf believes that the ability of these to be taken up into cells has been overstated.
In RXi’s research it has noticed that most RNA remains outside cells unless a delivery vehicle is used or modifications are made to induce spontaneous cellular uptake, which is how sdRNA enters.
RXi has established in-house sdRNA manufacturing that is sufficient for current research.
GeRPS targets macrophages
RXi also presented data on its glucan encapsulated RNAi particles (GeRPS), which are an oral formulation capable of targeting macrophages and reducing systemic inflammatory response.
The formulation uses a beta-glucan particle that enables it to be transported through the lining of the gut and then be taken up by macrophages. Once inside the RNA decreases macrophage activation, which helps to reduce inflammation.
Since GeRPS targets just one cell type it can be delivered at lower doses than other treatments, according to Woolf.