Arrowhead Research Corporation (NASDAQ: ARWR), a nanomedicine company with development programs in RNA therapeutics and obesity, today announced that it has acquired Alvos Therapeutics, Inc. (formerly known as Mercator Therapeutics, Inc.), a privately-held company that licensed a large platform of proprietary human-derived homing peptides from MD Anderson Cancer Center (MDACC) and the method for their discovery. The technology, designed to specifically bind and enter tumor cells and the vasculature supporting tumors, is thought to be the world’s largest library of human-derived targeting agents, representing thousands of unique peptide sequences. These targeting sequences can be linked to Arrowhead’s siRNA delivery vehicles as well as to traditional small molecule drugs to preferentially shuttle them into target cells. As such, the new platform is a natural addition to Arrowhead from both an operational and strategic standpoint, and it represents a significant leap forward in targeted therapeutics. MDACC has already achieved clinical proof of concept in targeting metastatic prostate cancer with one of the sequences, and Alvos has multiple other anti-cancer development programs in the pipeline. Alvos was co-founded in 2010 by the MDACC developers of the technology, Drs. Renata Pasqualini and Wadih Arap, along with Mark Leuchtenberger, CEO of Rib-X Pharma, and Dr. Roy Lobb. Dr. Lobb, who became Alvos’ CSO, is an experienced biotech executive and entrepreneur who also founded Avila Therapeutics which was sold earlier this year for a total potential payout of nearly $1bn including $350m upfront. At MDACC, Drs. Pasqualini and Arap used a technique called phage display to generate a vast library of specific peptides that home to both known and novel receptors. The process has generated powerful data in two primary areas: (1) new receptors were discovered that are present primarily or solely on the surface of specific cell types of interest, including cancer cells; and (2) peptides were identified that specifically bind these and previously known receptors and are rapidly internalized by the cells of interest. Importantly, this has been performed in terminal cancer patients, therefore the novel receptors and targeting peptides were identified in human patients with spontaneous disease, including metastases. The acquisition also enables Arrowhead to further expand the library by working with Drs. Pasqualini and Arap to generate additional data with more patient screening at MDACC. Arrowhead intends to apply the new technology for targeting their proprietary DPC and RONDEL™ siRNA delivery platforms. In addition, the peptides can be linked to small molecule cancer drugs to create a new class of drugs, “Peptide-Drug Conjugates”, or PDCs, designed to preferentially accumulate at and inside tumors. This new class has the potential to significantly advance cancer treatment by decreasing side effects, increasing efficacy, and/or decreasing dose of traditional therapies.