The Safety, Tolerability, PK and PD of GSK2586881 in Patients With Acute Lung Injury

The acute respiratory distress syndrome (ARDS) is a form of severe acute lung injury (ALI)
characterized by hypoxemic respiratory failure (the lungs are unable to absorb oxygen to the
arterial blood) and non-cardiogenic pulmonary edema (accumulation of fluid in the lungs). The
syndrome may be caused by direct or indirect injury to the lungs. It is associated with a
mortality rate of up to 40-50%. There are no marketed pharmacologic therapies for this
devastating syndrome.

This study aims to assess the safety, tolerability and pharmacodynamics of GSK2586881, a
recombinant human angiotensin converting enzyme type 2 (rhACE2).

ACE2 is involved in the Renin-Angiotensin System (RAS), which controls blood pressure,
electrolytes and intravascular fluid volume. A key function of rhACE2 is believed to be the
cleavage of Angiotensin II (Ang II) to Ang (1-7), which have opposing physiological roles.
Elevated levels of Ang II are associated with vasoconstriction, inflammation, fibrosis,
vascular leak, and sodium absorption. Ang (1-7) appears to be a counterregulatory protein in
the RAS; associated with vasodilation, anti-proliferation, antiinflammation, and reduced
vascular leak. It has been observed that levels of Ang II are increased in humans with ALI/
ARDS. It is expected that the reduction of Ang II should have a positive impact on ALI and
ARDS.

Inclusion Criteria:

- Male or female, 18 - 80 years of age (inclusive)

- Diagnosis of ALI with acute onset of PaO2/FiO2 ratio less than or equal to 300, and
bilateral infiltrates consistent with pulmonary edema on frontal chest radiograph. The
infiltrates may be patchy, diffuse, homogeneous, or asymmetric, and requirement for
positive pressure ventilation via an endotracheal tube, and no clinical evidence of
left atrial hypertension

- Cause of ALI thought to be associated with infection, sepsis, pneumonia, aspiration,
or similar as judged by the PI and/or medical monitor

- The subject must be randomized into the study within 48 hours from the time of
diagnosis of ALI

- Period of hemodynamic stability (e.g. 4-6 hours) prior to the initiation of study
treatment not requiring resuscitative measures with stable pressor requirements. In
this study low-dose arginine vasopressin is not considered a pressor, and is permitted
in Parts A and B.

- If mechanically ventilated, duration of mechanical ventilation must be less than 72
hours before dosing begins

- BMI within the range 19.0 - 38.0 kg/m2 inclusive

- The subject or legal decision maker is capable of giving written informed consent,
which includes compliance with the requirements and restrictions listed in the consent
form.

- QTcB or QTcF less than 450 msec; or QTc less than 480 msec in subjects with Bundle
Branch Block.

- Alanine aminotransferase (ALT) less than 5 x Upper Limit of Normal (ULN); bilirubin
less than or equal to 1.5 x ULN.

Exclusion Criteria:

- Subjects whose clinical condition is deteriorating rapidly or any subject for whom the
investigator does not consider there is a reasonable expectation that they will be
able to complete the study.

- Known positive Hepatitis B surface antigen, Hepatitis C antibody or HIV antibody

- Current or chronic history of liver disease (Child Pugh score of greater than or equal
to 10), or known hepatic or biliary abnormalities (with the exception of Gilbert's
syndrome or asymptomatic gallstones).

- Known history of substance abuse or alcohol abuse, within 6 months of the study
causing chronic liver disease such as cirrhosis, chronic ascites or portal
hypertension, or known evidence of withdrawal syndrome within the past 6 months.

- The subject has participated in a clinical trial and has received an investigational
product within the following time period prior to the first dosing day in the current
study: 30 days, 5 half-lives or twice the duration of the biological effect of the
investigational product (whichever is longer).

- Inability to discontinue use of Angiotensin converting enzyme type 1 inhibitors or
Angiotensin receptor blockers.

- Patients requiring high doses of loop diuretics with significant intravascular volume
depletion, as assessed clinically

- History of sensitivity to any of the study medications, or components thereof or a
history of drug or other allergy that, in the opinion of the investigator or GSK
Medical Monitor, contraindicates their participation

- Pregnant females as determined by positive serum or urine hCG test prior to dosing

- Lactating females

- Unwillingness or inability to follow the procedures outlined in the protocol

- Subject is legally incapacitated (e.g. a prisoner)

- History of sensitivity to heparin or heparin-induced thrombocytopenia

- Unstable Hemoglobin (Hb less than 7) at time of drug infusion

- Malignancy or other irreversible condition for which 6 month mortality is estimated to
be greater than 50%

- Arterial blood pH less than 7.1 or serum HCO3 - less than 15 (if ABG not available)
before infusion is started

- Known severe chronic respiratory disease:

- known Forced Expiratory Volume in 1 second (FEV1)/ Forced Vital Capacity (FVC) less
than 45% predicted, or

- known chronic hypercapnia (PaCO2 greater than 45 mmHg) or chronic hypoxemia (PaO2 less
than 55 mmHg) on FiO2 =0.21, or

- known FEV1 less than 15 ml/kg (e.g. 1L for 70 kg person), or

- known radiographic evidence of chronic interstitial infiltration, or

- known hospitalization within the past six months for respiratory failure (PaCO2
greater than 50 mmHg or PaO2 less than 55 mmHg, or oxygen saturation less than 88% on
FiO2 = 0.21), or

- known chronic restrictive, obstructive, neuromuscular, chest wall, or pulmonary
vascular disease resulting in severe exercise restriction

- Known history of neuromuscular disease that would affect time on mechanical
ventilation or impairs ability to ventilate spontaneously

- Vasculitis with diffuse alveolar hemorrhage

- Lung transplantation

- Pre-existing renal failure on hemodialysis or peritoneal dialysis requiring renal
replacement therapy

- A patient will be excluded if in the judgement of the Principle Investigator or GSK
medical monitor their participation could jeopardize the health of the subject or the
integrity of the study.