The objective of this study is to evaluate the effect of LJPC-501 infusion on mean arterial pressure (MAP) as assessed by standard of care vasopressor dose reduction in pediatric patients with catecholamine-resistant hypotension (CRH). In addition, this study will evaluate the safety and tolerability of LJPC-501 in pediatric patients, evaluate changes in catecholamine and other vasopressor doses over time, evaluate the change in MAP over time, and the change in Pediatric Logistic Organ Dysfunction-2 (PELOD-2) scores.

Inclusion Criteria:

Male and female paediatric patients with catecholamine-resistant hypotension associated with distributive shock.

1. Paediatric patients > 2 years (ie, > 24 months) to < 18 years of age at enrolment.
2. Patients requiring a sum norepinephrine-equivalent dose > 0.1 μg/kg/min to maintain age-appropriate target MAP for a minimum of 2 hours and a maximum of 48 hours prior to initiation of study drug.
3. Patients must have a clinical diagnosis of distributive shock in the opinion of the treating team and the Investigator.
4. Patients are required to have central venous access, which is expected to remain present for the duration of study drug treatment.
5. Patients are required to have an indwelling arterial line, which is expected to remain present for at least the first 48 hours of study drug treatment.
6. Patients must have received at least 40 mL/kg of crystalloid or colloid equivalent over the initial 24-hour resuscitation period, and must be adequately volume resuscitated in the opinion of the Investigator, prior to starting study drug.
7. Parent(s) or legal guardian(s) is willing and able to provide informed consent and assist the patient in complying with all protocol requirements.

Exclusion Criteria:

1. Patients who are ≤ 2 years (24 months) of age or ≥ 18 years of age at enrolment.
2. Patients with a standing Do Not Resuscitate order.
3. Patients diagnosed with acute occlusive coronary syndrome requiring pending intervention.
4. Patients on veno-arterial (VA) extracorporeal membrane oxygenation (ECMO).
5. Patients who have been on veno-venous (VV) ECMO for less than 6 hours.
6. Patients with a clinical suspicion of cardiogenic shock based on echocardiogram.
7. Patients who have a history of asthma or are currently experiencing bronchospasm requiring the use of inhaled bronchodilators and who are not mechanically ventilated.
8. Patients with acute mesenteric ischaemia or a history of mesenteric ischaemia.
9. Patients with active bleeding AND an anticipated need of multiple transfusions (within 48 hours of Screening).
10. Patients with active bleeding AND haemoglobin < 7 g/dL.
11. Patients with an expected lifespan of < 12 hours or expected withdrawal of life support within 24 hours of Screening.
12. Patients with a known allergy to mannitol.
13. Patients who are currently participating in another clinical trial using an investigational drug not approved in that member country unless specifically approved by the Sponsor.
14. Patients of childbearing potential who are known to be pregnant at the time of Screening.