'Far Bigger than Cancer Vaccines'

Billionaire investor Randall Kirk is so convinced that there's a way to make old chemotherapy drugs less toxic that he's taking a stake in "maverick" biotech company Ziopharm Oncology, says Forbes' Robert Langreth in his Treatments blog. Kirk's synthetic biology company Intrexon is also pushing a novel DNA therapy that Kirk thinks will be "far bigger that cancer vaccines," Langreth says. In an effort to keep the price of cancer treatments low, companies like Ziopharm are trying to reduce the toxic side effects of old chemotherapy drugs and make them more efficient. Its lead drug is called palifosfamide, which is a new version of ifosfamide — a drug currently in use to treat cancer, but is far too toxic for most people, Langreth says. But Kirk's real interest, he adds, is in using synthetic biology to create DNA-based drugs that cause cells to produce tumor-killing chemicals. Intrexon is paying $11.6 million for a 12.5 percent stake, and could increase the stake to 20 percent if Ziopharm brings any DNA-therapy drugs to a second-stage trials, Langreth says, adding that if Intrexon's DNA-based drugs work, then Ziopharm's efforts to reduce the side effects of chemotherapy drugs will be almost insignificant, however "the companies would split the profits on any DNA therapeutic that results."