This is a randomized, double-blind, single dose, dose-escalation study to evaluate the safety, tolerability, and pharmacokinetics of NCTX (PEGylated Liposomal Iodixanol Injection) administered intravenously to healthy volunteers. In addition, computed tomography (CT) scans will be acquired to measure radiographic density in regions of interest (ROI) at times from 3-5 hours and up to 72 hours following NCTX administration.

Inclusion Criteria:

• Healthy, nonsmoking men and women 18 to 55 years of age
• Body Mass Index (BMI) between 18.5 and 30.0 kg/m2
• Serum creatinine within normal range and calculated creatinine clearance of 80 mL/min/1.73 m2 or greater

Exclusion Criteria:

• Concurrent enrollment in another clinical trial or treatment with any investigational products or therapies within 30 days prior to dosing
• History of infusion reactions to liposomes, nanoparticles, monoclonal antibodies, or intravenously administered materials
• History of allergic/anaphylactoid-like reactions attributed to iodinated contrast agents or other components of the formulation
• Disturbances in normal fat metabolism, or total cholesterol greater than 240 mg/dL
• Pregnant or nursing women
• Exposure to significant radiation within 1 year, or previous CT scan within 5 years prior to check-in