Chronic Nausea and Vomiting in Patients with Normal Gastric Emptying Using the Enterra® Therapy System (NAVIGATE)

The purpose of this research study is to determine if the Enterra® Therapy System can decrease nausea and vomiting symptoms and improve the quality of life for patients with chronic nausea, with or without vomiting, that have normal gastric emptying.

Participants in this study will have an Enterra® Therapy System implanted and be assigned to a study group. Participants will answer daily questions about their nausea and vomiting symptoms and quality of life impacts with their smart device. Participants will answer quality of life questionnaires about their symptoms at study visits. Participants will be involved in this study for approximately twelve months after their study group is assigned.

Eligibility Criteria:
Inclusion Criteria:

* Willing and able to complete the informed consent process
* Stated willingness to comply with all study procedures and availability for the duration of the study
* Aged ≥18 years at time of informed consent
* Chronic, drug-refractory nausea that: a) has been present for more than 6 months, and b) has been active within the last 3 months prior to consent
* Patient is able to complete ANMS GCSI-DD surveys on a compatible smart device with: a) a minimum of four (4) ANMS GCSI-DD entries per week for two consecutive weeks, and b) an average ANMS GCSI-DD score for nausea severity of ≥2.5 during the same two-week period
* Refractory or intolerant to two or more of the following antiemetic drug classes: antihistamines, phenothiazines, serotonin type 3 receptor antagonists, dopamine type 2 receptor antagonists, anticholinergics, neurokinin receptor antagonists
* Medically stable, in the opinion of the investigator, during the month prior to consent, with no planned modifications to medical therapy during the course of the study
* Normal gastric emptying as assessed by a qualifying gastric emptying test performed within 1 year prior to consent
* Normal upper endoscopy within 1 year prior to consent (e.g., absence of obstructions, ulcers, or cancers in the esophagus, stomach, or duodenum)

Exclusion Criteria:

* Cognitive impairment or other characteristic that would limit a patient's ability to complete study requirements
* Evidence of a delayed gastric emptying test result within 2 years of consent
* Documented gastrointestinal (GI) obstruction or pseudo-obstruction
* History of primary swallowing disorders
* History of primary psychogenic vomiting
* History of primary eating disorder
* History of cyclic vomiting syndrome
* History of rumination syndrome
* History of scleroderma
* History of amyloidosis
* History of cannabis hyperemesis syndrome
* Active H. pylori infection
* Evidence of bezoar during most recent endoscopy
* Previous gastric surgery of any type
* Uncontrolled thyroid disorder, in the opinion of the investigator
* History of seizures disorders
* Hemoglobin A1c \>8.0%
* Peritoneal dialysis or unstable hemodialysis
* Parenteral or enteral nutritional support
* History of organ transplant, chronic pancreatitis, gross malabsorptive syndromes, celiac disease, or inflammatory bowel disease
* Other GI tract diseases and disorders that the investigator believes may have caused the patient's drug-refractory nausea and/or vomiting
* Malignancy (with the exception of basal cell carcinoma of the skin) currently present, initially diagnosed or recurring within 5 years of consent
* Opioid use
* Current cannabis/cannabinoid use that exceeds: 3 days of usage per week, or 2 occurrences during each day of use, or 3 grams of total usage per week
* Heavy alcohol use, defined as: for men, consuming five or more drinks on any day or 15 or more per week; for women, consuming four or more drinks on any day or 8 or more per week
* Injection of Botox into the pyloric sphincter within 6 months of consent
* Active major levels of anxiety/depression, as determined by the investigator
* History of other clinically significant disease, or any other condition which, in the opinion of the Investigator, would jeopardize the safety of the patient or impact the validity of the study results
* Life expectancy \<1 year
* Pregnant or breastfeeding at the time of consent or intend to become pregnant during the study
* Any underlying disease leading to follow-up by MRI outside of current MR conditional indications
* Glucagon-like peptide 1 (GLP-1) agonist drug use in 12 months prior to consent
* Participation in other investigational clinical studies
* Existing or prior gastric electrical stimulator implantation