A multisite Phase III study of the safety and efficacy of a new manganese chloride-based gastrointestinal contrast agent for MRI of the abdomen and pelvis

The purpose of this study was to evaluate the safety and efficacy of a mang anese chloride-based oral magnetic resonance (MR) contrast agent during a P hase III multisite clinical trial. Two hundred seventeen patients were enro lled who were already scheduled for MRI of the abdomen and/or pelvis. In th is group of patients, it was postulated that the use of an oral agent would better allow discrimination of pathology from bowel. Patients with known g astrointestinal pathology including peptic ulcer disease, inflammatory bowe l disease, obstruction, or perforation were excluded to minimize confoundin g variables that could affect the safety assessment. Of these 217 patients, 18 received up to 900 mL of placebo, and 199 patients were given up to 900 mL of a manganese chloride-based oral contrast agent, LumenHance(R) (Bracc o Diagnostics, Inc.). Safety was determined by comparing pre- and post-dose physical examinations, vital signs, and laboratory examinations and by doc umenting adverse events. Efficacy was assessed by unblinded site investigat ors and two blinded reviewers who compared pre- and post-dose T1- and T2-we ighted MRI scans of the abdomen and/or pelvis. In 111 (57%) of the 195 case s evaluated for efficacy by site investigators (unblinded readers), MRI aft er LumenHance provided additional diagnostic information. Increased informa tion was found by two blinded readers in 52% and 51% of patients, respectiv ely. In 44/195 cases (23%) unblinded readers felt the additional informatio n would have changed patient diagnosis and in 50 patients (26%), it would h ave changed management and/or therapy. Potential changes in patient diagnos is or management/therapy were seen by the two blinded readers in 8-20% of p atients. No clinically significant post-dose laboratory changes were seen. Forty-eight patients (24%) receiving LumenHance and four patients (22%) rec eiving placebo experienced one or more adverse events. Gastrointestinal tra ct side effects were most common, seen in 29 (15%) of LumenHance patients a nd in 3 (17%) of the placebo patients. LumenHance is a safe and efficacious oral gastrointestinal contrast agent for MRI of the abdomen and pelvis. J. Magn. Reson. Imaging 1999;10:15-24. (C) 1999 Wiley-Liss, Inc.