- More than four weeks must have elapsed since any prior systemic therapy at the time the patient receives the preparative regimen, and patients toxicities must have recovered to a grade 1 or less (except for toxicities such as alopecia or vitiligo). Six weeks must have elapsed since prior Ipilimumab (MDX-010) therapy to allow antibody levels to decline, and patients who have previously received MDX-010 must have a normal colonoscopy with normal colonic biopsies.