Renibus Announces First Patient Enrolled in PROTECT Phase 3 Study of RBT-1 to Reduce Post-operative Complications After Cardiothoracic Surgery

Pivotal trial will evaluate the effect of RBT-1 as a preconditioning agent in people undergoing cardiothoracic surgery

Estimated 600K CABG and valve repair surgeries in US/year, creating a large initial market for RBT-1

PROTECT enrollment on track, NDA filing anticipated early 2026

SOUTHLAKE, Texas, Oct. 25, 2023 /PRNewswire/ — Renibus Therapeutics® (“Renibus”), a clinical-stage biopharmaceutical company focusing on the prevention and treatment of cardio-renal and metabolic diseases, today announced that the first patient has been dosed in the pivotal Phase 3 PROTECT trial of RBT-1, the Company’s first-in-a-new-class preconditioning agent under investigation to reduce post-operative complications following cardiothoracic surgery. PROTECT is expected to be conducted at approximately 35 sites in the United States and Canada.

Post-operative complications from cardiothoracic surgery represent a major unmet medical need. In the United States (US), there are approximately 600,000 CABG, valve repair, and related procedures conducted annually, with 66% of patients having complications that result in $6.5 billion in unnecessary healthcare costs. This represents a significant and growing initial market for RBT-1, which if approved, would be the first and only approved pharmacological therapy to reduce the risk of post operative complications following cardiothoracic surgery.

RBT-1 (stannic protoporfin/iron sucrose), a fixed dose combination product given once intravenously over 1-2 hours, 24-48 hours before surgery, is a potent inducer of anti-inflammatory, antioxidant and iron-scavenging pathways. In a completed Phase 2 study, RBT-1 demonstrated statistically significant positive data in primary and several secondary endpoints, with reduced time in the ICU, shortened patient recovery time and fewer hospital readmissions.

“We are pleased to initiate our PROTECT Phase 3 study of RBT-1. This milestone represents a significant step towards addressing the unmet needs associated with post-operative complications after cardiothoracic surgery, and underscores our commitment to transforming this treatment landscape,” said Frank Stonebanks, Co-CEO of Renibus. “With our pivotal trial now underway in our PROTECT program, we are considering ways to expand the opportunity with RBT-1 across a wide spectrum of procedures and post-operative complications, including potentially transplant surgeries, TAVR’s (trans aortic valve replacements) and thoracic aortic aneurysms. We believe that RBT-1 has broad “pipeline-in-a-product” potential, and we look forward to executing well in Phase 3 and bringing our product to patients in need.”

PROTECT is a Phase 3, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Effect of RBT-1 on Reducing the Risk of Post-Operative Complications in Subjects Undergoing Cardiac Surgery. The study is a randomized, double-blind, multi-center, placebo-controlled trial evaluating the effect of RBT-1 in approximately 400 patients. The primary endpoint is a severity-based composite hierarchy using the Win-Ratio or Finkelstein-Schoenfeld Method that includes the following: death, AKI requiring dialysis, ICU days, and 30-day cardiopulmonary readmission rates.   Secondary and exploratory objectives include time on the ventilator, need for blood products, new onset atrial fibrillation, delirium, hospital length of stay, cost effective analyses and safety. Top line results are expected mid-2025.

Charles A. Mack, MD, FACS, Associate Professor of Cardiothoracic Surgery, New York-Presbyterian Hospital, Weill Cornell Medicine, added, “The cardiac surgery community is grateful for Renibus’ commitment to bringing a new treatment option forward for patients undergoing cardiac surgery.  RBT-1 is a potentially transformational pre-conditioning product, and I am enthusiastic about the initial results demonstrated in our patients.”

About RBT-1

RBT-1 (stannic protoporfin/iron sucrose) is a potent inducer of anti-inflammatory, antioxidant and iron-scavenging pathways currently in Phase 3 [NCT # 06021457] for its lead indication to reduce post-operative complications following cardiothoracic surgery.  Renibus completed the Phase 2 study of RBT-1 (NCT04564833) in February 2023 and announced positive final results from this study in May 2023. In October 2023, Renibus initiated enrollment and administration of RBT-1 in its PROTECT Phase 3 pivotal study.

RBT-1 was granted Breakthrough Therapy designation status from the U.S. FDA to reduce the risk of complications in patients undergoing cardiothoracic surgery.

About Renibus Therapeutics

Renibus is a clinical stage biopharmaceutical company dedicated to treating, improving and extending patients’ lives by developing products to prevent disease progression, improve outcomes and protect against organ damage associated with cardiorenal and metabolic diseases.  Renibus’ first-in-class lead program is RBT-1, currently being evaluated in a pivotal Phase 3 PROTECT study. RBT-3 is a novel, low molecular weight iron nanoparticle that has the potential to rapidly resolve iron deficiency and may reduce the risk of cisplatin-induced nephrotoxicity. RBT-9 (stannic protoporfin) is a potent anti-inflammatory and antioxidant drug with broad spectrum anti-viral properties. It has been investigated in a 42-patient Phase 2, randomized, placebo-controlled trial in high-risk patients with COVID-19. The data from this trial indicated the RBT-9 has the potential to significantly improve clinical outcomes in life threatening viral infections. Additional pre-clinical work is underway to help inform the clinical development strategy.

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Investor and Media Contact:

Amy Conrad
Juniper Point

Business Development Contact
Frank Stonebanks
Co-CEO, Renibus