Effect of RBT-1 on Reducing the Risk of Post-Operative Complications in Subjects Undergoing Cardiac Surgery

Inclusion Criteria:

1. Male or female, ≥18 years of age at Screening.

2. Planned to undergo non-emergent CABG and/or cardiac valve surgery requiring CPB;non-emergent surgery must allow for study drug infusion ≥24 but ≤48 hours prior tosurgery.

3. If female, subjects must use an effective method of birth control or abstain fromsexual relations with a male partner (unless has undergone tubal ligation orhysterectomy or is at least 1 year postmenopausal) for the duration of their studyparticipation.

4. If male, subjects must use an effective method of birth control or abstain fromsexual relations with a female partner for the duration of their studyparticipation, unless the subject has had a vasectomy ≥6 months prior to infusionwith study drug.

5. Willingness to comply with all study-related procedures and assessments.

Exclusion Criteria:

1. Surgery planned to occur <24 hours from the start of study drug infusion.

2. Presence of acute organ dysfunction (AKI, acute decompensated heart failure, acuterespiratory failure, stroke, etc) as assessed by the Investigator at the time ofScreening.

3. Surgery to be performed without CPB.

4. Chronic kidney disease (CKD) requiring dialysis.

5. Hypokalemia and/or hypomagnesemia within 24 hours prior to study drug infusion;electrolytes can be replenished if low.

6. Cardiogenic shock or immediate requirement for inotropes, vasopressors, or othermechanical devices, such as intra-aortic balloon pump (IABP).

7. Known history of cancer within the past 2 years, except for carcinoma in situ of thecervix or breast, early-stage prostate cancer, or adequately treated non-melanomacancer of the skin.

8. Known or suspected sepsis at time of Screening.

9. Asplenia (anatomic or functional).

10. History of hemochromatosis, iron overload, or porphyria.

11. Known hypersensitivity or previous anaphylaxis to SnPP or FeS.

12. Female subject who is pregnant or breastfeeding.

13. Participation in a study involving an investigational drug or device within 30 daysprior to study drug infusion or throughout participation in REN-007.

14. In the opinion of the Investigator, for any reason, the subject is an unsuitablecandidate to receive RBT-1.