In the US, approximately half of the targeted colorectal cancer (CRC) screening population avoid having a colonoscopy due to the extensive preparation and invasiveness associated with procedure. While the colonoscopy itself usually takes only 35 to 40 minutes, preparation typically lasts two days and involves eating plain food and inducing diarrhoea with laxatives, to clean out the colon and give the camera the best view possible.
The procedure can be uncomfortable and lead to embarrassment, meaning many patients choose to be sedated, but this can be an inconvenience in itself – driving is prohibited for 24 hours after sedation, which can be particularly challenging for those living in rural areas.
As a result of these impracticalities, colonoscopies have a poor adherence rate, with a 2018 study estimating just 38% adherence overall. Despite the fact colonoscopies have exceptional sensitivity and specificity when it comes to detecting precancerous polyps in asymptomatic patients during routine screening – up to 98% and 91% respectively – most patients who undergo the procedure won’t be able to get the best screening possible. The associated inconvenience and discomfort are, for many people, simply too much.
This lack of adherence is sobering, as CRCs are the third most common cancers diagnosed in the US, excluding skin cancers. While the rate of diagnoses in people aged 55 or over have dropped about 3.6% each year between 2007 and 2016, they increased about 2% each year in those under 55.
Once a person turns 50, most medical experts recommend they undergo a colorectal cancer screening colonoscopy every five to ten years, but this can begin earlier depending on a person’s health and background.
CRC screening via an ingestible X-ray capsule
But what if CRC screening didn’t have to be this way? Israeli-American medtech firm Check-Cap has envisioned a different type of CRC screening, carried out via an X-ray-powered ingestible capsule. Known as the C-Scan system, this procedure is designed with patient convenience in mind, and removes many of the unpleasant elements associated with colonoscopy.
Check-Cap is designed to be used as a screening device for healthy people, not necessarily those that have symptoms that could indicate a CRC.
“In the landscape of CRC screening, solutions such as colonoscopy generate a lot of barriers for patients who are required to go through preparation, sedation, inflation of the colon and many other things that act as barriers to patients who aren’t necessarily adhering to those procedures,” says Check-Cap CEO Alex Ovadia.
Once the ingestible C-Scan Cap capsule has been swallowed, it travels along the gastrointestinal tract and scans the inner lining of the colon, emitting ultra-low dose X-ray beams. As it does so, it actively communicates with C-Scan Track, three miniaturised patches worn on the patient’s back, which contain an integrated positioning, control and recording system. C-Scan Track stores all of the information gathered by the capsule, before the device is naturally excreted and the data can be processed in C-Scan View, a cloud-based analysis platform clinicians use to process the capsule’s data.
The software uses the data to construct 2D and 3D maps of the inner surface of the colon. These maps can then be used to check for any potentially malignant structures that could need future investigation. The procedure is able to bypass all of the inconvenience of a colonoscopy, but still provide good results when scanning the colon.
Ovadia says: “We just provide patients with an ingestible capsule and attach the tracking system to them, and they can move around and do normal things like eating, showering and driving their cars. The only restriction we tell them is that they are not allowed to go and perform any sort of jogging or exercise.”
Sacrificing sensitivity and specificity to boost adherence
However, the sensitivity of C-Scan isn’t as good as that of a colonoscopy. According to Check-Cap’s latest study data, the suite has demonstrated a sensitivity of 76% and a specificity of 82% for polyps greater than 10mm. While this pales in comparison to the accuracy of the colonoscopy, Ovadia believes this doesn’t actually matter. He says the C-Scan suite has the potential to improve adherence so much that this compensates for the discrepancy.
Ovadia says: “We believe our device is good enough to be launched with its current performance since we provide a good solution to combat low adherence. Of course, we intend to continue to improve our performance going forward.
“Also, there could be many cases where the colonoscopy cannot completely view the colon itself, either due to insufficient cleansing or anatomical limitations that cannot allow the colonoscope to get around the entire colon. We believe that only our procedure can provide a non-invasive, prep-less solution that can make more people adhere.”
The next stage for Check-Cap’s C-Scan suite is a pivotal study, which it aims to initiate in 2021. The company plans to conduct the study on a population of healthy people without any history of polyps and aims to enrol approximately 700 to 800 patients.
Ovadia says: “If all goes well according to our plans, then 2022 we anticipate completion of the pivotal study. That means by 2023 we believe we could be on the market in the US.”
Of course, Check-Cap aren’t the only firm to take a capsule-based approach to CRC screening.
Researchers at Purdue University, for example, have built a way to swallow a tool that acts like a colonoscopy, which takes samples of bacteria instead of imaging the colon. Capsule endoscopies, where a pill with a built-in camera is swallowed and used to image the intestines, have been common for years – but these involve a certain amount of prep-work. The C-Scan suite’s creators maintain that only their invention can provide patients with a non-invasive, prep-free CRC screening.
Ovadia says: “This is the first and only device that is utilising prep-less CRC screening. We believe that we can address unmet needs and increase significantly the adherence of people for colonoscopy, and by that measure save many lives.”