The two firms said this new high throughput screening (HTS) assay "gives pharmaceutical companies the ability to rapidly and efficiently screen vast libraries of compounds" in order to identify those that interrupt the lifecycle of HIV through a novel mechanism of action - the inhibition of transfer RNA (tRNA). "This technology has the potential to discover new classes of medicines for the treatment of HIV that may overcome resistance mechanisms associated with current therapies," said the companies. According to Trana, so far about 30 drugs have been launched on the US market for the treatment of HIV infections but collectively they represent only five different classes working at just four different sites of action in the HIV replicative cycle. "And despite the enhanced potency of the more recently introduced products, resistance continues to be a major challenge for managing patients with HIV," said the firm. There is still an unexploited target for antiretroviral drugs - disrupting human tRNA used by the virus during HIV replication. But until recently, several hurdles, including the stability of the RNA-RNA binding during testing, had prohibited investigation of tRNA as a drug target. Working in collaboration with SRI, Trana refined its technology to overcome those obstacles with a HTS method, therefore opening the way to discovery and development of HIV drugs that work using this new mechanism of action, the company explained. "By using precision robotics, highly accurate low volume liquid handling devices, sensitive detectors and powerful data processing software, the HTS assay that was developed will allow researchers to quickly conduct millions of tests that identify active compounds," the companies said. They claim that using this newly validated assay, the HTS Center at SRI can screen 50,000 compounds per day. "We consider the HIV HTS assay as a major breakthrough in the development of new techniques in the early-stage drug discovery and development process," said David Harris, director of Drug Discovery Business Development at Southern Research. "We are now ready for the commercialisation and licensing of this technology to discover new classes of compounds that will inhibit HIV via a unique mechanism of action," added Steve Peterson, CEO of Trana Discovery. Trana Discovery is seeking diverse collections of compounds or compounds with known bioactivity against HIV but unknown mechanism of action to identify candidates for drug development. Southern Research is a not-for-profit CRO that also conducts basic and applied research in the areas of preclinical drug discovery and drug development, advanced engineering, environmental research and energy production. To date, Southern Research has discovered six FDA-approved cancer drugs and discovered six additional drugs that are currently in late stage preclinical and early clinical trials.