I'll just mention that although many mAbs have been tremendously successful in controlling various diseases (and being a staple of many lymphoma treatments used

I'll just mention that although many mAbs have been tremendously successful in controlling various diseases (and being a staple of many lymphoma treatments used currently) there are indeed very good reasons for caution, see e.g. http://en.wikipedia.org/wiki/TGN1412#Clinical_trials http://en.wikipedia.org/wiki/TGN1412#Clinical_trials In this case this was a phase I trial. For those unfamiliar with trial design, phase I is not meant to assess the efficacy of the drug but just its safety in humans. It was provided at 1/500th of the maximum safe dose determined in macaques.