Evaluate the safety and systemic absorption of OMS201 following exposure during ureteroscopy.

OMS201 is being developed to facilitate endoscopy of the ureters and to reduce postoperative discomfort, such as pain, frequency, urgency and/or difficult urination following endoscopic surgery to remove a urinary tract stone.

• Urinary Calculi
• Urinary Stones
• Urinary Tract Stones

• Drug: OMS201
• Drug: Vehicle

• Experimental: Drug
• Placebo Comparator: Vehicle

Inclusion Criteria:

• Subject is undergoing unilateral ureteroscopic removal of renal collecting system or ureteral stones located in the ureter with a maximum stone diameter of 12 mm, for which general anesthesia will be used.
• Subject's physical examination is within normal limits or examination is clinically non-significant for purposes of the study as determined by the Investigator, and subject is in good general health.
• Subject's laboratory evaluations are within normal limits or evaluations are clinically non-significant as determined by the Investigator.
• Female subject of childbearing potential who is using an effective method of birth control within at least 14 days prior to surgery and has a negative pregnancy test.
• Subject is at minimal risk from anesthesia and is classified according to the American Society of Anesthesiologists Physical Status Classification as either PS-1 or PS-2.
• Subject's body mass index is between 19 and 35, inclusive, based on the Body Mass Index Table.

Exclusion Criteria:

• Subject taking a prohibited medication.
• Subject who has had a renal transplant, has a single kidney or has evidence of a compromised renal function as measured by abnormal serum creatinine, as judged by the Investigator, or who has evidence of urinary tract infection, or has prior history of open or laparoscopic surgery, or any history of an ureteral stricture.
• Subject who has congenital anomalies that would engender an increased procedural safety risk such as ureteropelvic junction obstruction resulting in severely dilated renal pelvis, duplicated urinary collecting system, horseshoe kidney or vascular anomalies such as renal arteriovenous fistulas or papillary necrosis.
• Subject has bilateral renal or ureteral stones requiring concurrent ureteroscopic removal.
• Subject with clinically significant hypotension at Screening.
• Subject who has a present condition or history of any clinically significant uncontrolled gastrointestinal, cardiovascular, hepatic, renal, hematological, endocrine, neurological, psychiatric, connective tissue, respiratory or other medical disorder as determined by the Investigator.
• Subject on chronic diuretic use.
• Subject who has taken or used an investigational drug or device within 30 days prior to the day of surgery.