The colon cleansing efficacy and safety of Polyethylene Glycol-3350, Electrolytes, and Ascorbate for Oral Solution was evaluated in two randomized, actively-controlled, multi-center, investigator-blinded trials in adult patients scheduled to have an elective colonoscopy.

In Study 1, patients were randomized to one of the following two colon preparation treatments: 1) 2 liters of Polyethylene Glycol-3350, Electrolytes, and Ascorbate for Oral Solution with 1 additional liter of clear liquid split into two doses (during the evening before and the morning of the colonoscopy) and 2) 4 liters of polyethylene glycol plus electrolytes solution (4L PEG + E) split into two doses (during the evening before and the morning of the colonoscopy). Patients were allowed to have a morning breakfast, a light lunch, clear soup and/or plain yogurt for dinner. Dinner had to be completed at least one hour prior to initiation of the colon preparation administration.

The primary efficacy endpoint was the proportion of patients with effective colon cleansing as judged by blinded gastroenterologists on the basis of videotapes recorded during the colonoscopy.

The blinded gastroenterologists graded the colon cleansing twice (during introduction and withdrawal of the colonoscope) and the poorer of the two assessments was used in the primary efficacy analysis.

The efficacy analysis included 308 adult patients who had an elective colonoscopy. Patients ranged in age from 18 to 88 years old (mean age about 59 years old) with 52% female and 48% male patients. Table 3 displays the results.

4L PEG+E’s responder rate was not significantly higher than Polyethylene Glycol-3350, Electrolytes, and Ascorbate for Oral Solution’s responder rate.

In Study 2, patients were randomized to one of the following two colon preparation treatments: 1) 2 liters of Polyethylene Glycol-3350, Electrolytes, and Ascorbate for Oral Solution with 1 additional liter of clear liquid in the evening prior to the colonoscopy and 2) 90 mL of oral sodium phosphate solution (90 mL OSPS) with at least 2 liters of additional clear liquid during the day and evening prior to the colonoscopy. Patients randomized to Polyethylene Glycol-3350, Electrolytes, and Ascorbate for Oral Solution therapy were allowed to have a morning breakfast; a light lunch; and clear soup and/or plain yogurt for dinner. Dinner had to be completed at least one hour prior to initiation of the colon preparation administration.

The primary efficacy endpoint was the proportion of patients with effective colon cleansing as judged by the colonoscopist and one blinded gastroenterologist (on the basis of videotapes recorded during the colonoscopy). In case of a discrepancy between the colonoscopist and the blinded gastroenterologist, a second blinded gastroenterologist made the final efficacy determination. 

The efficacy analysis included 280 adult patients who had an elective colonoscopy. Patients ranged in age from 21 to 76 years old (mean age about 53 years old) with 47% female and 53% male patients. Table 4 displays the results.

Polyethylene Glycol-3350, Electrolytes, and Ascorbate for Oral Solution’s responder rate was not significantly higher than OSPS’s responder rate.