The EAC S aureus pneumonia was based on clinical, radiographic, and microbiologic criteria. Clinical criteria: 1 major criteria (PaO2/FiO2 ratio < 240 mmHg maintained for at least 4 hours or decrease in PaO2/FiO2 by >= 50 mmHg maintained for at least 4 hrs or a need to initiate non-invasive mechanical ventilation or re-initiate invasive mechanical ventilation because of respiratory failure or worsening of respiratory status); and at least 2 of minor criteria (systemic signs of infection, production of purulent sputum/endotracheal secretions, new onset of cough, physical examination findings consistent with pneumonia/pulmonary consolidation, dyspnea, and/or tachypnea). Radiographic criteria: new or worsening infiltrate consistent with pneumonia on chest X-ray obtained within 24 hrs of event. Microbiologic criteria: at least 1 culture positive for S aureus (respiratory specimen, or blood, or pleural fluid aspirate or lung tissue culture during episode of pneumonia).

An mITT population included all participants, who received any dose of study drug and analyzed according to their randomized treatment group.

An adverse event (AE) is any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. TEAEs are defined as events present at baseline that worsened in intensity after administration of study drug or events absent at baseline that emerged after administration of study drug.

As-treated population included all participants, who received any dose of study drug and analyzed according to the treatment they actually received.

An AE is any untoward medical occurrence in a participant who received study drug without regard to possibility of causal relationship. TEAEs are defined as events present at baseline that worsened in intensity after administration of study drug or events absent at baseline that emerged after administration of study drug.

As-treated population included all participants, who received any dose of study drug and analyzed according to the treatment they actually received.

A serious adverse event (SAE) is an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly. TEAEs are defined as events present at baseline that worsened in intensity after administration of study drug or events absent at baseline that emerged after administration of study drug.

As-treated population included all participants, who received any dose of study drug and analyzed according to the treatment they actually received.

An AESI is one of scientific and medical interest specific to understanding of the study drug and may have required close monitoring and rapid communication by the investigator to the sponsor. An AESI may have been serious or non-serious.

As-treated population included all participants, who received any dose of study drug and analyzed according to the treatment they actually received.

An NOCD defined as a newly diagnosed medical condition that is of a chronic, ongoing nature. It is observed after receiving the study drug and is assessed by the investigator as medically significant.

As-treated population included all participants, who received any dose of study drug and analyzed according to the treatment they actually received.

Maximum observed serum concentration (Cmax) of MEDI4893 is reported.

An Intent-to-treat (ITT) population included all randomized participants and were analyzed according to their randomized treatment group. Participants who had quantifiable pharmacokinetic (PK) samples were analyzed for this outcome measure.

Area under the serum concentration time curve from time zero to last measurable concentration (AUC[0 - Last]) of MEDI4893 is reported.

An ITT population included all randomized participants and were analyzed according to their randomized treatment group. Participants who had quantifiable PK samples were analyzed for this outcome measure.

Observed serum concentration of MEDI4893 through 30 days post dose (C30) is reported. Serum concentration of MEDI4893 through 30 days post dose accounted the overall concentration of MEDI4893 measured on specified time points (Days 1, 4, 8, 15, 22, and 30).

An ITT population included all randomized participants and were analyzed according to their randomized treatment group. Participants who had quantifiable PK samples were analyzed for this outcome measure.

Observed serum concentration of MEDI4893 through 90 days post dose (C90) is reported. Serum concentration of MEDI4893 through 90 days post dose accounted the overall concentration of MEDI4893 measured on specified time points (Days 1, 4, 8, 15, 22, 31, 61, and 91).

An ITT population included all randomized participants and were analyzed according to their randomized treatment group. Participants who had quantifiable PK samples were analyzed for this outcome measure.

Participants with ADA-positive at any of Day 31, Day 61, or Day 91 post-baseline assessments were always counted as "positive" at post-baseline.

As-treated population included all participants, who received any dose of study drug and analyzed according to the treatment they actually received.