Researchers at the Indian Institute of Science say they have made a breakthrough in the fight against hepatitis C by modifying a dendrimer to create a nanovector for the delivery of siRNA to the liver.
|The Indian Institute of Science's Saumitra Das|
The team showed that injection of the modified propyl ether imine (PETIM) dendrimer resulted in a 77% reduction in hepatitis C RNA levels, at least in mice, according to the Bangalore Mirror.
"The major hurdle that we face (in drug therapy) is the targeted delivery of any drug" said Saumitra Das, Indian Institute of Science professor of microbiology and cell biology and author of the study published in the journal Nanoscale. "Having a specific delivery system allows us to reduce the dosage of the drug and make it more effective."
The nanovector helps ensure transportation and uptake of the siRNA to the liver, and protects it from degrading within the body prior to delivery.
"PETIM, till today is the most non-toxic dendrimer that has been developed," added study author and PhD study Abirami Lakshminarayanan.
The naturally occurring RNAi paradigm's discovery in 1998 earned scientists Andrew Fire and Craig Mello a Nobel Prize in 2006 to great fanfare, and subsequent investments from Big Pharmas Roche ($RHHBY), Novartis ($NVS) and Merck ($MRK), eventually were canceled due to the difficulty of drug delivery of RNAi candidates across cell membranes.
But research from the likes of the Indian Institute of Science shows that the modality still holds promise, as investors and the medical community anxiously await the first commercialized drug from the RNAi specialists that now dominate the field, such as Alnylam ($ALNY) and Arrowhead Research ($ARWR).
The liver is the most promising site for siRNA uptake and delivery. That makes hepatitis C a good target for RNAi research.
The World Health Organization says that more than 130 million people have hep C, and about a half-million people die from it every year. New antivirals from Gilead ($GILD) and AbbVie ($ABBV) are very effective, but have a list price of up to $94,500 for a 12-week course, putting them out of reach of many in developing countries like India.
- here's more from the Bangalore Mirror