A Study to Compare the Efficacy and Safety of 2 Dosing Regimens of IV Infusions of AZD9773 (CytoFab™) With Placebo in Adult Patients With Severe Sepsis and/or Septic Shock

• Evaluate the affect of AZD9773 on 7-day mortality in patients with severe sepsis or septic shock [ Time Frame: Over 7 days following first dose ] [ Designated as safety issue: Yes ]
• Evaluate the affect of AZD9773 on 28-day mortality in patients with severe sepsis or septic shock [ Time Frame: Over 28 days following first dose ] [ Designated as safety issue: Yes ]
• To characterize the safety and tolerability of AZD9773 in patients with severe sepsis or septic shock through the assessment of adverse events, mortality, ECGs, vital signs, laboratory tests, and physical examination [ Time Frame: Over 90 days following first dose ] [ Designated as safety issue: Yes ]

The primary purpose of this study to evaluate the effect of two different doses of AZD9773 (CytoFab™) versus placebo on ventilator free days (VFDs) over the first 28 days after the start of dosing with AZD9773 in patients with severe sepsis and/or septic shock, who are already receiving appropriate standard of care treatment for sepsis.

• Severe Sepsis
• Septic Shock

• Drug: AZD9773
  A single loading dose following by up to 9 maintenance doses; doses to be given every 12 hours over a period of 5 days
  Other Name: CytoFab™
• Drug: Placebo
  Placebo

• Experimental: 1
  AZD9773 250/50 units/kg
  Intervention: Drug: AZD9773
• Experimental: 2
  AZD9773 500/100 units/kg
  Intervention: Drug: AZD9773
• Placebo Comparator: 3
  Intervention: Drug: Placebo

Inclusion Criteria:

• Adults with a first episode of sepsis during this hospitalisation and objective evidence of infection that requires parenteral antibiotics.
• At least 2 of 4 SIRS criteria in the 24 hours before organ dysfunction (must include either fever OR elevated white blood cells [WBC])
• Cardiovascular or respiratory dysfunction.

Exclusion Criteria:

• Immunocompromising comorbidities or concomitant medications:

  1. Advanced human immunodeficiency virus (HIV) infection (CD4 ≤50/mm3).
  2. Stage III or IV cancer.
  3. Haemopoietic or lymphoreticular malignancies not in remission.
  4. Receiving radiation therapy or chemotherapy.
  5. Stem cell, organ or bone marrow transplant in the past 6 months.
  6. Absolute neutrophil count <500 per μL.
  7. High dose steroids or other immunocompromising drugs.

• Concomitant diseases:

  1. Deep seated fungal infection or active tuberculosis.
  2. Cirrhosis with portal hypertension or Childs-Pugh Class C.
  3. History of chronic hypercarbia, respiratory failure in past 6 months or use of home oxygen in the setting of severe chronic respiratory disease.
  4. Neuromuscular disorders that impact breathing/spontaneous ventilation.
  5. Quadriplegia.
  6. Cardiac arrest in the past 30 days.
  7. New York Heart Association functional Class IV due to heart failure or any disorder.
  8. Burns over > 30% of body surface area.

• Medication and allergy disqualifications.

  1. Treatment with anti-TNF agents within the last 8 weeks.
  2. Previously received ovine derived products (CroFab™, DigiFab™).
  3. Sheep product allergy or allergy to latex, papain, chymopapain.