Efficacy and Safety of SP16 in Preventing Acute Kidney Injury in At-risk Subjects With Chronic Kidney Disease Undergoing Elective Cardiac Surgery Using the Heart-lung-machine

CKD stages 4-5 with eGFR \<30 ml/min/1.73 m2 pre-surgery as determined by CKD EPI.

Previous cardiac surgery.

Person has a kidney transplant or another solid organ transplant.

Person is scheduled for intermittent or continuous renal replacement therapy (dialysis).

Known diagnosis of dementia or other clinical signs of mental illness that will prevent full understanding.

Known diagnosis of severe COPD (Gold 3) and/or FEV1 \< 1 l/s.

Heart failure with severity of symptoms according to NYHA IV.

Heart failure with impaired cardiac pump function (LVEF \<35%).

Acute onset or ongoing sepsis - sepsis is defined as the presence of a confirmed or putative infection, along with a dysregulated systemic immune reaction leading to organ dysfunction.

Clinical signs of a currently active infection including endocarditis requiring antibiotic treatment.

Clinical signs of an acute viral infection.

Serious underlying disease(s) or very poor general medical condition, so that in the investigator's judgment the person is not expected to survive ICU or hospital stay.

Patient who has an active (requiring treatment) malignancy or history within 5 years prior to enrollment in the study, of solid, metastatic or hematologic malignancy with the exception of basal or squamous cell carcinoma of the skin that has been removed.

Administration of iodinated contrast agent within 24 hours prior to cardiac surgery

Recent (discontinued in the last 14 days before V1a or V1b) or current treatment with immunosuppressive drugs, including, but not limited to, high dose corticosteroids \[\> 1 mg/kg of prednisone equivalent\], tumour necrosis factor alpha blockers, or ciclosporin.

Current regular use of anti inflammatory drugs such as NSAID, with discontinuation not possible. (however, if these medications are discontinued in the last 10 days before V2, the participant is eligible to participate). ASA up to 100 mg per day is allowed.

Systemic corticosteroid therapy (any dose).

Known active chronic inflammatory disease (including, but not limited to, rheumatoid arthritis or systemic lupus erythematosus).

Known allergy to SP16 or to other ingredients of the IMP.

Person who is not willing to use highly effective contraceptive measures (according to CTFG recommendations v1.2).

Pregnant women.

Breastfeeding women.

Current participation in another interventional clinical study (register studies or non-interventional, observational studies excluded).

Employee or direct relative of an employee of the study site, the CRO, or the Sponsor.

What this study is about