FDA Approvals: New Colon-Cleansing Drug for Colonoscopy Preparation

CLINICAL CONTEXT

The US Food and Drug Administration (FDA) has approved a new colon-cleansing drug, a dual-acting stimulant and osmotic laxative, for colonoscopy preparation. A previously available, low-volume oral phospho-soda preparation was removed from the market for safety reasons.

The advantage of a small-volume solution for bowel preparation is greater patient compliance, as use of large-volume cleansing preparations may be a deterrent to some patients for having the procedure. Increased use of screening colonoscopy and cleaner bowel allowing high-quality colonoscopy may improve screening rates and cancer detection.

STUDY SYNOPSIS AND PERSPECTIVE

The FDA has approved Prepopik, a new bowel preparation for cleansing the colon before colonoscopy.

When it becomes available, the dual-acting stimulant and osmotic laxative will be notable for its low volume, representing "the lowest volume active ingredient colon preparation available — with 10 ounces of prep solution," according to a news release.

The preparation consists of 2 packets of sodium picosulfate, magnesium oxide, and citric acid. In a split-dose regimen, patients dissolve the first packet of powder into water and drink the orange-flavored solution the night before a scheduled colonoscopy, and then do the same for the second packet the morning of the procedure.

If that split-dose regimen cannot be performed, patients may also take the drug as a day-before regimen in the afternoon and evening before a colonoscopy.

Patients are also advised to drink additional fluids during and after use of the preparation to reduce the risk for fluid and electrolyte imbalance.

The FDA's approval was based on two phase 3 trials involving about 1200 adult patients who were scheduled for colonoscopies. The patients were randomly assigned to either the split-dose or day-before regimen or to a control preparation consisting of a polyethylene glycol plus electrolyte solution and two 5-mg bisacodyl tablets, administered entirely the day before the colonoscopy.

In both studies, the new preparation achieved the primary endpoint of successfully cleansing patients' colons based on the Aronchick Scale and demonstrated noninferiority to the control preparation.

The most common adverse effects related to the new preparation in study 1, involving a split-dose treatment group (n = 305) compared with the control group (n = 298), were nausea (2.6% vs 3.7%), headache (1.6% vs 1.7%), and vomiting (1.0% vs 3.4%).

In study 2, involving a day-before dose of the new preparation (n = 296) vs the comparator (n = 302), the adverse effects were similar, including nausea (3.0% vs 4.3%), headache (2.7% vs 1.7%), and vomiting (1.4% vs 2.0%).

"The choice of a bowel cleansing regimen for colonoscopy should be based on a patient's health and personal preferences," said Victoria Kusiak, MD, deputy director of the Office of Drug Evaluation III in the FDA's Center for Drug Evaluation and Research, in an FDA news release. "[The] approval provides a new treatment option for patients and doctors to consider."

According to Ronald P. Fogel, MD, a gastroenterologist from the Digestive Health Center of Michigan in Chesterfield, the idea of a small-volume solution is an important selling point for a bowel preparation.

"A major advantage of Prepopik is the smaller volume," he told Medscape Medical News. "Patients dread taking the large-volume cleansing preparations, and for some it is a deterrent for having the procedure."

The market is open for a product that helps alleviate the discomfort of a large-volume preparation, he added.

"The oral phospho-soda prep that was removed from the market for safety reasons was very popular with patients," Dr. Fogel said. "Prepopik has the potential to fill a niche in the cleansing procedure market because of the relatively small volume ingested.

"Any changes that increase the use of screening colonoscopy and allow for high-quality colonoscopy [are] a huge benefit to our patients."

Gastroenterologist Michael L. Weinstein, MD, underscored the importance of the bowel preparation in a successful colonoscopy.

"Less volume means the patient is more likely to be able to complete it," said Dr. Weinstein, from Capital Digestive Care in Bethesda, Maryland.

"I tell patients the most unpleasant part of a colonoscopy is the prep, but the most important part is the prep," he said.

"If the colon is not clean, it doesn't matter how good the colonoscopist is at making the procedure comfortable or easy; if we can't see, the procedure may be a failure, and that's a lot of effort to have to waste."

More information on the new colon-cleansing drug is available on the FDA Web site.

Dr. Fogel and Dr. Weinstein have disclosed no relevant financial relationships.

CLINICAL IMPLICATIONS

• The FDA has approved a new bowel preparation drug, a low-volume, dual-acting stimulant and osmotic laxative, for colon cleansing before colonoscopy. This new preparation will be available as a split-dose regimen of 2 packets of powdered sodium picosulfate, magnesium oxide, and citric acid, to be mixed in water. Patients should be encouraged to drink additional fluids during and after use of the new preparation.
• FDA approval was based on data from two randomized phase 3 trials enrolling approximately 1200 adults undergoing colonoscopy. Preparation in the control group consisted of a solution containing polyethylene glycol and electrolytes, and two 5-mg bisacodyl tablets, given on the day before the procedure. Both studies reached the primary endpoint for the new preparation and showed noninferiority to the control preparation for successful colon cleansing.
• In these two randomized phase 3 trials, the most common adverse effects associated with the new bowel preparation, and also reported in the control group, were nausea, headache, and vomiting.