A new drug composed of pig whipworm eggs may help people fight autoimmune diseases because the eggs somehow manipulate the human immune system, instructing it to stop attacking itself. The drug, called trichuris suis ova and developed by Coronado Biosciences, is entering human trials for patients with Crohn's disease, and the company hopes the drug will one day be useful for other disorders such as rheumatoid arthritis and psoriasis.