Proving once again that CAR-T is now one of the hottest fields in cancer drug development, Boston-based Ziopharm Oncology ($ZIOP) is expanding its R&D collaboration with Intrexon ($XON) to include the personalized immuno-oncology technology. In CAR-T, a patient's T cells are extracted, reengineered with chimeric antigen receptors to launch a personalized immune system attack on specific cancer cells and then reinjected into patients, where they can repopulate to fight cancer. Intrexon boasts that its industrial engineering expertise will help resolve some of the lingering questions regarding toxicity, side effects and manufacturing efficiency. Right now the two are in the preclinical stage and plan to update the program later this year. The partnership between Intrexon and Ziopharm dates back to early 2011. Last year Ziopharm was hit hard after its lead drug failed in Phase III. Release