The primary objective is to determine the safety and efficacy of the C2 CryoBalloon™ Swipe Ablation System ("CryoBalloon Swipe") used at increasing doses.

The procedure will be performed on an outpatient basis, and the CryoBalloon Swipe will be used for all ablations following the instructions for use provided with the product.

Patients who meet the eligibility criteria will be assigned to one of the treatment groups and doses, depending on the order of their enrollment:

In phase I, the first 6 patients will be treated with Dose 1 (lowest).

All patients will have to undergo 8 week (±1 week) follow-up EGD to evaluate efficacy of the dose before the study continues.

If the follow-up endoscopies show that Dose 1 eradicates ≥80% of the treated BE (by median percentage) and no SAE's are reported, this dose is defined as the therapeutic dose and enrollment will proceed to phase II.

If Dose 1 eradicates <80% of the treated BE, enrollment in Phase I will continue at the next highest dose. Treatment doses will be escalated in this manner until the earlier of a dose-related Serious Adverse Event (SAE) or determination of the therapeutic dose based on endoscopic exam.

When the therapeutic dose is determined, the study will proceed to Phase II to generate additional safety and efficacy data.

Phase II

Phase II will confirm the safety and efficacy of the therapeutic dose found in Phase I.

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Dose-related SAEs include pain in the treatment area greater than 6 (on VAS) on 24 hours and seven (7) days post-treatment; symptomatic stricture requiring an additional EGD with endoscopic dilation before the first follow-up EGD; symptomatic stricture at follow-up EGD; or any stricture (symptomatic or asymptomatic) preventing passage of the diagnostic endoscope at follow-up EGD. Any other serious adverse events within 30 days after treatment will also be evaluated by the Data and Safety Monitoring Board (DSMB) for relationship to the dose and severity.

When a Dose-related serious adverse event occurs, the Holding Rule will be invoked and enrollment at that dose will be held until the DSMB has evaluated the event.

Inclusion Criteria:

1. Patients with flat-type (Paris type 0-IIb) BE esophagus, with an indication for ablation therapy, meaning:

   • Diagnosis of LGD or HGD in BE (confirmed by baseline histopathological analysis), OR
   • Residual BE with any grade of dysplasia after endoscopic resection

2. Prague Classification Score C≤3

3. Patients should be ablative-naïve (no previous ablation therapy of the esophagus)

4. Older than 18 years of age at time of consent

5. Operable per institution's standards

6. Provides written informed consent on the IRB-approved informed consent form

7. Willing and able to comply with follow-up requirements

Exclusion Criteria:

1. Esophageal stenosis or stricture preventing advancement of a therapeutic endoscope.
2. Any endoscopically visualized lesion such as ulcers, masses or nodules.
3. History of locally advanced (>T1a) esophageal cancer
4. History of esophageal varices
5. Prior distal esophagectomy
6. Active esophagitis LA grade B or higher
7. Severe medical comorbidities precluding endoscopy
8. Uncontrolled coagulopathy
9. Pregnant or planning to become pregnant during period of study
10. Patient refuses or is unable to provide written informed consent
11. Participation in another study with investigational drug within the 30 days preceding or during the present study
12. General poor health, multiple co-morbidities placing the patient at risk or otherwise unsuitable for trial participation

Data will not be shared.