Mr. Richard Muruve reports

ROYAL COLUMBIAN HOSPITAL BEGINS PATIENT RECRUITMENT IN ARCH BIOPARTNERS' PHASE II TRIAL OF LSALT PEPTIDE TARGETING CS-AKI

Royal Columbian Hospital (RCH) has begun patient recruitment in Arch Biopartners Inc.'s continuing phase II trial evaluating LSALT peptide as a new drug to prevent acute kidney injury in patients undergoing on-pump cardiac surgery.

Royal Columbian Hospital, located in New Westminster and part of Fraser Health, is the ninth site to be activated globally for the study and the fourth site to recruit patients in Canada.

Patient recruitment into the trial is continuing at Toronto General Hospital, part of University Health Network; St. Michael's Hospital, part of Unity Health Toronto; and the University of Calgary, Cumming School of Medicine.

"Royal Columbian Hospital joining the CS-AKI phase II trial strengthens the company's clinical presence in Canada, with active patient dosing continuing smoothly at three other major Canadian sites," said Richard Muruve, chief executive officer of Arch Biopartners. "All activated sites have shown strong dedication to the study and have been effective at recruiting and dosing patients. Together with the ongoing Pontiak trial, the Arch team is looking forward to future progress and remains focused on continued execution across both phase II AKI programs."

Arch continues to evaluate additional sites to support enrolment in the CS-AKI phase II trial. The company is in feasibility discussions with cardiac surgery centres in Canada and the United States, including three prospective sites in the United States and one additional site in Ontario (through Clinical Trials Ontario).

About the CS-AKI phase II trial

Cardiac-surgery-associated acute kidney injury is a common complication following on-pump (heart-lung machine) cardiac surgery and can lead to longer hospital stays and worse outcomes. The trial is designed to evaluate whether LSALT peptide can reduce the rate of AKI in this setting.

The CS-AKI phase II trial is an international, multicentre, randomized, double-blind, placebo-controlled study of LSALT peptide with a recruitment target of 240 patients. The primary objective of the trial is to evaluate the percentage of subjects with acute kidney injury in each treatment group within seven days following on-pump cardiac surgery, as defined by the KDIGO (Kidney Disease: Improving Global Outcomes) criteria.

Details of the phase II trial can be viewed on the ClinicalTrials.gov website under NCT05879432.

Other corporate developments

The company has also announced that its board of directors has granted a total of 150,000 stock options to a new director pursuant to the company's stock option plan and the requirements of the TSX Venture Exchange. The grant of stock options to the new director represents remuneration for serving on the board and managing the company's affairs for the annual period ending March 30, 2027.

Each of these stock options is exercisable into one common share of the company at a price of $1.05 per share for a period of 10 years, effective April 29, 2026, and will be subject to all necessary regulatory approvals.

About Arch Biopartners Inc.

Arch Biopartners is a therapeutic biotechnology company developing novel drugs for acute kidney injury (AKI) and chronic kidney disease (CKD). The company is advancing an integrated program that includes new treatments targeting inflammation- and toxin-related kidney injury.

Arch's development pipeline includes:

• LSALT peptide: in a phase II trial targeting cardiac-surgery-associated AKI;
• Cilastatin: a repurposed drug in a phase II trial targeting toxin-induced AKI;
• CKD platform: next-generation therapeutics targeting chronic kidney disease.

These assets represent distinct, mechanism-based approaches to treating and preventing common causes of kidney damage. Together, they target unmet needs in kidney care across both chronic and acute indications, affecting more than 800 million people around the world. Both lead programs are currently enrolling patients at Canadian clinical sites, with additional North American sites in development.

The company has 67,933,289 common shares outstanding.

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