Prep Shortages, Coverage Restrictions Create New Colonoscopy Barriers

Alicia Ault

February 18, 2022

In April 2021, Express Scripts stopped covering low-volume bowel preparations in its National Preferred Formulary, a move that had the potential to affect many of the 75 million Americans covered by that pharmacy benefit manager's programs, according to the American Society for Gastrointestinal Endoscopy (ASGE).

For gastroenterologists and their patients, it was an action that added insult to injury. The COVID-19 pandemic had already led to shortages of various preps, causing many thousands of Americans to forego colonoscopies. One study estimated that there was a 95% decline in weekly colorectal cancer screenings in the first half of 2020.

Just as screenings were returning to pre-pandemic levels, the Express Scripts coverage change threatened to create a new barrier for those already hesitant, especially since the prep is what patients most loathe about colonoscopy, said the gastroenterologists interviewed for this story.

Almost a year later, not much has changed. Bowel prep shortages persist, and some insurers and pharmacy benefit management (PBM) companies are restricting coverage of certain prescription preps or instituting higher co-pays.

Gastroenterologists are having to delay procedures and patients are canceling appointments; some never return.

"I and many of my colleagues are very concerned that we are going to see an increase in advanced colon polyps and colon cancer," said Jennifer A. Christie, MD, professor of medicine in the digestive diseases division at Emory University School of Medicine in Atlanta, Georgia, and vice president of the ASGE.

Obstacles to getting the right prep "not only delays the care, but the negative outcomes could be horrible," agreed Tauseef Ali, MD, clinical assistant professor at the University of Oklahoma and a member of the American College of Gastroenterology's board of governors.

For the majority of patients, a wait might not be an issue, said Christian Stevoff, MD, assistant professor of medicine at Northwestern University Feinberg School of Medicine in Chicago. But a delayed diagnosis would be significant for those with larger polyps or cancer in the colon, he said.

"It's a major problem for those people that it does affect," Stevoff told Medscape.

He noted that his practice had to delay around 3000 procedures in 2020, and while they have since caught up, approximately 25% of cases are being delayed right now for a variety of reasons. Most of those are in patients deemed to be low risk though, he said.

PBMs: "A Parasitic Infection to Our Healthcare System"

Shortages of preps have been a persistent headache, but restrictions such as those instituted by Express Scripts have become a bigger problem, said some gastroenterologists.

Express Scripts did have several exceptions to its prohibition on coverage of low-volume preps. First, it could be approved if the patient had failed with a polyethylene glycol (PEG)–based prep like GoLYTELY. It could also be approved if the patient had tried MoviPrep and failed, if MoviPrep was unavailable, or if the patient has phenylketonuria or glucose-6-phosphate dehydrogenase deficiency.

Cigna-owned Express Scripts is one of three PBMs — along with CVS Caremark and OptumRX (owned by UnitedHealth Group) — that control 85% of prescription drug benefits in the United States, according to a 2019 investigation of the industry by the New York State Senate.

Express Scripts did not return requests by Medscape for comment on its bowel prep coverage, and CVS Caremark declined to participate. A spokesperson for OptumRX told Medscape that the PBM provides bowel preps at "$0 cost-share," but only for health plan sponsors that are subject to Affordable Care Act regulations that require providing colonoscopies under such a payment structure. The company did not provide further information to Medscape.

For some gastroenterologists, the anger toward PBMs is palpable. Ali calls PBMs "a parasitic infection to our healthcare system."

"Keeping track of these bowel prep coverages has become a nightmare," he said, noting that every payer seems to have its own preferred prep. "We have a dedicated nurse whose only job is to keep tabs on this, and she's unable to because it's just getting out of control."

Some preps are contraindicated for patients, Ali said. Yet even in those cases, it's difficult to get the alternatives covered. It often comes down to a joint effort by a pharmacist, the patient, and Ali's office staff to get coverage for a medically necessary prep.

If it's an emergency, Ali said, "either our patients bite the bullet and pay the price, or we have to come up with alternative solutions that may not lead to an optimal bowel preparation. It defeats the whole purpose of having a good bowel preparation and giving them a good outcome."

He added that "there are a lot of patients who cancel their colonoscopies out of frustration," because the bowel prep is not available or too expensive, and that some patients choose to simply not reschedule.

Christie's experience is similar. Sometimes patients must be rescheduled because "we could not get the prep in a timely fashion for them to be ready for their procedure." Bringing back patients can be hard; they are busy, or they can't get a ride or time off work or coverage for caregiving, she said. Ultimately, "some patients do decide to either defer or decline screening."

The hassles also have the potential to exacerbate existing health disparities, she added.

Stevoff, the gastroenterologist at Northwestern, said cancellations are a concern, but to his knowledge, none of his patients have quit in frustration.

He said that because "most of the [preps] are equivalent to each other," he often gives preference to what's available.

He does tell patients that they may have a higher co-pay. For some that may be fine for what is only a once every 5- or 10-year payment. For others who cannot afford the cost, it may mean spending time trying to convince the insurer to pay for a prep that is not normally covered, he said.

A Step Backwards

Stevoff understands why payers might have preferred preps.

"As long as the outcomes are equivalent, I don't think they're going to be willing to pay for a prep that's three or four times more expensive for a night of inconvenience for the patient," he said.

David Johnson, MD, professor of medicine and chief of gastroenterology at Eastern Virginia Medical School in Norfolk, said he's mystified by moves to limit bowel preps.

"Having to do an end-run to figure out what preps we can get for a patient is a step backwards," he said.

Douglas Rex, MD, distinguished professor emeritus of medicine at Indiana University School of Medicine in Indianapolis, said it was dangerous to limit options.

"Trying to save relatively small amounts of money by restricting access to specific preps is seriously wrong-headed and a mistake," he said. "If you keep the big picture in mind, we're trying to keep people from getting colon cancer."

Johnson also noted that a poor-quality prep might lead to a poor-quality exam, which is associated with not only reduced adenoma detection rates but also a shortened interval for a repeat exam, which just adds costs to the system.

"The whole impact of colon cancer screening is to discover polyps and remove them to prevent cancer," Johnson said.

No Rhyme or Reason to Ongoing Shortages

Pandemic-related supply chain headaches have trickled down to bowel preps, which then lead to occasional delays in procedures.

"We have definitely seen shortages throughout most of the pandemic," Rex said. At various times, he added, low-volume or high-volume prescription preps have not been available in all pharmacies or not available in certain pharmacies.

The spotty supplies have created a hassle and add costs because his office staff spends time making calls to find an available prep, he said.

Christie described similar issues at her practice, where the shortages have been "a significant challenge and issue."

As of late January, some polyethylene glycol 3350-based preps were still in short supply or had been discontinued, according to the American Society of Health-System Pharmacists (ASHP). Two companies — Teva and Lupin — did not provide a reason for the lack of product. However, ASHP said the companies anticipated being able to provide supplies in February.

Many PEG-based prescription products have been on back order for some time, said Johnson, who tries to avoid the higher-volume PEG-based preps in favor of low-volume preps that are more tolerable to patients.

The lack of information about a reason for the shortages has led to speculation.

At the beginning of the COVID-19 pandemic, GoLYTELY, one of the more commonly used PEG-based preps, was not available at all, Ali said. It was his understanding that PEG was being used as an ingredient in COVID vaccines, which helped explain the shortage, at least initially.

Stevoff also heard this explanation but said he had come to believe it was an "urban myth," and added that he "never got confirmation from any of the companies" that they couldn't get PEG because it was being used for vaccines. He noted that shortages of some PEG-based preps have continued even though vaccine production has stabilized.

Over-the-Counter Alternatives Can Be "Hit or Miss"

With the price for all bowel preps — and co-pays — increasing in the last 2 years, some practices are directing patients how to mix up their own using over-the-counter (OTC) ingredients, which is likely to be less expensive.

The out-of-pocket cost for a four-liter, high-volume PEG-based prep might be $35-$50, according to GoodRx. Alternatives such as Suprep (sodium/potassium/magnesium) run $110-$120, according to the website, and a sodium phosphate-based prep, such as OsmoPrep, runs close to $300.

The OTC prep uses MiraLAX (PEG-based but without additional electrolytes mixed in) and bisacodyl (Dulcolax). Johns Hopkins University, Cleveland Clinic, and Memorial Sloan Kettering, among many other institutions, have advised patients to use the OTC do-it-yourself preps. It is a split prep, using 238 grams of MiraLAX mixed with 64 ounces of water or a sports drink (eg, Gatorade). The day before the procedure, patients take 2 bisacodyl (5 mg) tablets, followed by four 8-ounce glasses of a MiraLAX/water mixture. The same regimen is followed the day of the procedure.

There are mixed results on how adequately the regimen cleans the colon. A 2014 meta-analysis found that the MiraLAX-based prep was inferior in terms of bowel cleansing to PEG-based formulations pre-mixed with electrolyte solutions (PEG-ELS). There was no statistically significant difference in polyp detection between the two. In a 2011 analysis, researchers concluded that GoLYTELY was superior to MiraLAX in colon prep and adenoma detection.

The 2014 US Multi-Society Task Force on Colorectal Cancer Guidelines reported that the MiraLAX-based prep had less effective bowel preparation than 4-liter PEG-ELS solutions in at least one study, but that it appeared to be more tolerable for patients and associated with few adverse events. More study of its safety is "warranted and desirable," write the authors.

Even before the pandemic, Rex said his practice used the MiraLAX-based prep because it was less expensive, and "anecdotally it tends to be very well tolerated."

However, he noted that the regimen is not approved by the Food and Drug Administration (FDA).

"A lot of people don't like to use non-FDA approved preps because they're afraid of some liability if there is a complication," Rex said.

Ali added that he has advised patients to use the OTC preps, but the results can be "hit or miss."

Some patients can easily comply with the instructions and will have good results, but others may not have the education or understanding or may have underlying medical conditions that lessens the OTC formulation's effectiveness in getting a good cleanout, said Ali.

Stevoff has occasionally used the OTC prep but agrees that not all patients will be able to follow the directions.

"The more complicated a process is, the more likely it is that somebody will make a mistake," he said.

Alicia Ault is a Lutherville, Maryland-based freelance journalist whose work has appeared in publications including JAMA,, the New York Times, and the Washington Post. You can find her on Twitter @aliciaault.

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