Trial Outcomes & Findings for Dose-Ranging Study of GSK2140944 in the Treatment of Subjects With Suspected or Confirmed Gram-Positive Acute Bacterial Skin and Skin Structure Infections (NCT NCT02045797)

This study was conducted at 13 centers in the United States from 24 March 2014 to 22 July 2015.

A total of 126 participants were randomly assigned to study treatment (all randomized population). A total of 122 participants, who received study treatment, were included in the Modified Intent-to-Treat population (mITT) and safety populations. The mITT population is used in overall study numbers and demographic information.

Dose-Ranging Study of GSK2140944 in the Treatment of Subjects With Suspected or Confirmed Gram-Positive Acute Bacterial Skin and Skin Structure Infections

Cure rate and withdrawal rate data points was jointly assessed in a composite endpoint for all participants who received at least one dose of GSK2140944. Cure rate was defined as the percentage of participants exhibiting clinical improvement (=\>20% reduction in overall lesion area) at the early efficacy visit. Withdrawal rate was defined as the percentage of participants who withdrew from study treatment due to a drug-related adverse event (AE) at any point while on treatment.

The assessment was used to determine whether to continue the participant in the study. Clinical response was assessed as either a clinical success or a clinical failure and the clinical outcome was subsequently determined programmatically, based on the clinical response. Clinical success was defined as a reduction in the total surface area of the lesion (as calculated by digital imaging) of \>=20% compared to Baseline and no administration of additional antibacterial therapy for the lesion under study. Clinical failure was defined as death of participant; increase or insufficient decrease (i.e., \<20%) in the area (as calculated by digital imaging) of the lesion or administration of non-trial antibacterial drug therapy for treatment of the lesion under study before the primary efficacy endpoint assessment. In addition when the participant refused to consent to clinical examination, the clinical outcome was assessed as unable to determine with subsequent response as failure.

The assessment was used to determine whether to continue the participant in the study. Clinical response was assessed as either a clinical success or a clinical failure and the clinical outcome was subsequently determined programmatically, based on the clinical response. Clinical success was defined as a reduction in the total surface area of the lesion (as calculated by digital imaging) of \>=20% compared to Baseline and no administration of additional antibacterial therapy for the lesion under study. Clinical failure was defined as death of participant; increase or insufficient decrease (i.e., \<20%) in the area (as calculated by digital imaging) of the lesion or administration of non-trial antibacterial drug therapy for treatment of the lesion under study before the primary efficacy endpoint assessment. In addition when the participant refused to consent to clinical examination, the clinical outcome was assessed as unable to determine with subsequent response as failure.

The assessment was used to determine whether to continue the participant in the study. Clinical response was assessed as either a clinical success or a clinical failure and the clinical outcome was subsequently determined programmatically, based on the clinical response. Clinical success was defined as no increase in the total surface area of the lesion (as calculated by digital imaging) compared to post therapy visit and no further administration of antibacterial therapy for the lesion under study. Clinical recurrence was defined as death of participant; increase in the area of the lesion compared to post therapy visit or administration of additional antibacterial therapy for the lesion under study before the efficacy endpoint assessment for participants who were a clinical success at post therapy visit. In addition when the participant refused to consent to clinical examination, the clinical outcome was assessed as unable to determine with subsequent response as failure.

The microbiological outcome was determined by comparing Baseline bacteriology lesion sample, to the culture results at early efficacy visit. The corresponding microbiological response (success or failure) by participant was then assigned. Microbiological eradication or persistence was defined as culture documented elimination or presence of Baseline pathogens from a bacteriology specimen taken at early efficacy visit respectively. Participant was considered to have outcome of presumed microbiological eradication or persistence when the participant was a clinical success or clinical failure and no bacteriological specimen was obtained at early efficacy visit respectively. When the determination of Baseline pathogen microbiological response could not be made, the outcome was considered as unable to determine. The data for SA in lesion sample has been presented.

The microbiological outcome was determined by comparing Baseline bacteriology lesion sample, to the culture results at early efficacy visit. The corresponding microbiological response (success or failure) by participant was then assigned. Microbiological eradication or persistence was defined as culture documented elimination or presence of Baseline pathogens from a bacteriology specimen taken at early efficacy visit respectively. Participant was considered to have outcome of presumed microbiological eradication or persistence when the participant was a clinical success or clinical failure and no bacteriological specimen was obtained at early efficacy visit respectively. When the determination of Baseline pathogen microbiological response could not be made, the outcome was considered as unable to determine. The data for MRSA in lesion sample has been presented.

The microbiological outcome was determined by comparing Baseline bacteriology lesion sample, to the culture results at early efficacy visit. The corresponding microbiological response (success or failure) by participant was then assigned. Microbiological eradication or persistence was defined as culture documented elimination or presence of Baseline pathogens from a bacteriology specimen taken at early efficacy visit respectively. Participant was considered to have outcome of presumed microbiological eradication or persistence when the participant was a clinical success or clinical failure and no bacteriological specimen was obtained at early efficacy visit respectively. When the determination of Baseline pathogen microbiological response could not be made, the outcome was considered as unable to determine. The data for MSSA in lesion sample has been presented.

The microbiological outcome was determined by comparing Baseline bacteriology lesion sample, to the culture results at early efficacy visit. The corresponding microbiological response (success or failure) by participant was then assigned. Microbiological eradication or persistence was defined as culture documented elimination or presence of Baseline pathogens from a bacteriology specimen taken at early efficacy visit respectively. Participant was considered to have outcome of presumed microbiological eradication or persistence when the participant was a clinical success or clinical failure and no bacteriological specimen was obtained at early efficacy visit respectively. When the determination of Baseline pathogen microbiological response could not be made, the outcome was considered as unable to determine. The data for other Gram-positive aerobic pathogens in lesion sample has been presented.

The microbiological outcome was determined by comparing Baseline bacteriology lesion sample, to the culture results at early efficacy visit. The corresponding microbiological response (success or failure) by participant was then assigned. Microbiological eradication or persistence was defined as culture documented elimination or presence of Baseline pathogens from a bacteriology specimen taken at early efficacy visit respectively. Participant was considered to have outcome of presumed microbiological eradication or persistence when the participant was a clinical success or clinical failure and no bacteriological specimen was obtained at early efficacy visit respectively. When the determination of Baseline pathogen microbiological response could not be made, the outcome was considered as unable to determine. The data for all Gram-positive aerobic pathogens in lesion sample has been presented.

The microbiological outcome was determined by comparing Baseline bacteriology blood culture, to the culture results at early efficacy visit. The corresponding microbiological response (success or failure) by participant was then assigned. Microbiological eradication or persistence was defined as culture documented elimination or presence of Baseline pathogens from a bacteriology specimen taken at early efficacy visit respectively. Participant was considered to have outcome of presumed microbiological eradication or persistence when the participant was a clinical success or clinical failure and no bacteriological specimen was obtained at early efficacy visit respectively. When the determination of Baseline pathogen microbiological response could not be made, the outcome was considered as unable to determine. The data for SA, MRSA and all Gram-positive aerobic pathogens in blood sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at post therapy visit. Corresponding response (success or failure) was then assigned. Microbiological eradication or persistence was culture documented elimination or presence of Baseline pathogens from a specimen taken at post therapy visit respectively. Presence of pathogens which was presumed to be eradicated at early efficacy visit was microbiological recurrence. Presumed microbiological eradication or persistence was when there was a clinical success or failure and no bacteriological specimen was obtained at post therapy respectively. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at post therapy visit for pathogens presumed eradicated at early efficacy visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for SA in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at post therapy visit. Corresponding response (success or failure) was then assigned. Microbiological eradication or persistence was culture documented elimination or presence of Baseline pathogens from a specimen taken at post therapy visit respectively. Presence of pathogens which was presumed to be eradicated at early efficacy visit was microbiological recurrence. Presumed microbiological eradication or persistence was when there was a clinical success or failure and no bacteriological specimen was obtained post therapy respectively. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at post therapy visit for pathogens presumed eradicated at early efficacy visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for MRSA in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at post therapy visit. Corresponding response (success or failure) was then assigned. Microbiological eradication or persistence was culture documented elimination or presence of Baseline pathogens from a specimen taken at post therapy visit respectively. Presence of pathogens which was presumed to be eradicated at early efficacy visit was microbiological recurrence. Presumed microbiological eradication or persistence was when there was a clinical success or failure and no bacteriological specimen was obtained post therapy respectively. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at post therapy visit for pathogens presumed eradicated at early efficacy visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for MSSA in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at post therapy visit. Corresponding response (success or failure) was then assigned. Microbiological eradication or persistence was culture documented elimination or presence of Baseline pathogens from a specimen taken at post therapy visit respectively. Presence of pathogens which was presumed to be eradicated at early efficacy visit was microbiological recurrence. Presumed microbiological eradication or persistence was when there was a clinical success or failure and no bacteriological specimen was obtained post therapy respectively. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at post therapy visit for pathogens presumed eradicated at early efficacy visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at post therapy visit. Corresponding response (success or failure) was then assigned. Microbiological eradication or persistence was culture documented elimination or presence of Baseline pathogens from a specimen taken at post therapy visit respectively. Presence of pathogens which was presumed to be eradicated at early efficacy visit was microbiological recurrence. Presumed microbiological eradication or persistence was when there was a clinical success or failure and no bacteriological specimen was obtained post therapy respectively. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at post therapy visit for pathogens presumed eradicated at early efficacy visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at post therapy visit. Corresponding response (success or failure) was then assigned. Microbiological eradication or persistence was culture documented elimination or presence of Baseline pathogens from a specimen taken at post therapy visit respectively. Presence of pathogens which was presumed to be eradicated at early efficacy visit was microbiological recurrence. Presumed microbiological eradication or persistence was when there was a clinical success or failure and no bacteriological specimen was obtained post therapy respectively. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at post therapy visit for pathogens presumed eradicated at early efficacy visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at final follow up visit. Corresponding response (success or failure) was then assigned. Microbiological eradication was culture documented elimination of Baseline pathogens from a bacteriology specimen taken at final follow up visit. Presumed microbiological eradication was when there was a clinical success and no bacteriological specimen was obtained at final follow up visit. Culture documented presence of Baseline pathogens in a bacteriology specimen taken at final follow up visit was microbiological recurrence. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at final follow up visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for SA pathogen in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at final follow up visit. Corresponding response (success or failure) was then assigned. Microbiological eradication was culture documented elimination of Baseline pathogens from a bacteriology specimen taken at final follow up visit. Presumed microbiological eradication was when there was a clinical success and no bacteriological specimen was obtained at final follow up visit. Culture documented presence of Baseline pathogens in a bacteriology specimen taken at final follow up visit was microbiological recurrence. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at final follow up visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for MRSA pathogen in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at final follow up visit. Corresponding response (success or failure) was then assigned. Microbiological eradication was culture documented elimination of Baseline pathogens from a bacteriology specimen taken at final follow up visit. Presumed microbiological eradication was when there was a clinical success and no bacteriological specimen was obtained at final follow up visit. Culture documented presence of Baseline pathogens in a bacteriology specimen taken at final follow up visit was microbiological recurrence. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at final follow up visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for MSSA pathogen in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at final follow up visit. Corresponding response (success or failure) was then assigned. Microbiological eradication was culture documented elimination of Baseline pathogens from a bacteriology specimen taken at final follow up visit. Presumed microbiological eradication was when there was a clinical success and no bacteriological specimen was obtained at final follow up visit. Culture documented presence of Baseline pathogens in a bacteriology specimen taken at final follow up visit was microbiological recurrence. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at final follow up visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for other Gram-positive aerobic pathogens in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline lesion sample, to culture results at final follow up visit. Corresponding response (success or failure) was then assigned. Microbiological eradication was culture documented elimination of Baseline pathogens from a bacteriology specimen taken at final follow up visit. Presumed microbiological eradication was when there was a clinical success and no bacteriological specimen was obtained at final follow up visit. Culture documented presence of Baseline pathogens in a bacteriology specimen taken at final follow up visit was microbiological recurrence. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at final follow up visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for all Gram-positive aerobic pathogens in lesion sample has been presented.

Microbiological outcome was determined by comparing Baseline blood culture, to culture results at final follow up visit. Corresponding response (success or failure) was then assigned. Microbiological eradication was culture documented elimination of Baseline pathogens from a bacteriology specimen taken at final follow up visit. Presumed microbiological eradication was when there was a clinical success and no bacteriological specimen was obtained at final follow up visit. Culture documented presence of Baseline pathogens in a bacteriology specimen taken at final follow up visit was microbiological recurrence. Presumed microbiological recurrence was when there was a clinical failure and no bacteriological specimen was obtained at final follow up visit. When the determination of Baseline pathogen response could not be made, the outcome was unable to determine. Data for SA, MRSA and all Gram-positive aerobic pathogens in lesion sample has been presented.

Samples for assessment of PK parameter Cmax was done on at predose, 1, 2, 2.5, 3, 6, 12 hours post dose on Day 1 to 3. The first occurrence of the Cmax was determined directly from the raw concentration-time data. Data for participants while on IV therapy has been presented.

Samples for assessment of PK parameter Cmax was done at Predose, 1, 2, 3 hours after first orally administered drug and one predose time point anytime from Day 7 to 10. The first occurrence of the Cmax was determined directly from the raw concentration-time data. Data for participants while on oral dose therapy has been presented.

Samples for assessment of PK parameter tmax was done at predose, 1, 2, 2.5, 3, 6, 12 hours post dose on Day 1 to 3. The time at which Cmax was observed was determined directly from the raw concentration-time data. Data for participants while on IV therapy has been presented.

Samples for assessment of PK parameter tmax was done at Predose, 1, 2, 3 hours after first orally administered drug and one predose time point anytime from Day 7 to 10. The time at which Cmax was observed was determined directly from the raw concentration-time data. Data for participants while on oral dose therapy has been presented.

Samples for assessment of PK parameters AUClast and AUC0-tau was done at predose, 1, 2, 2.5, 3, 6, 12 hours post dose on Day 1 to 3. The AUC 0-t and AUC0-tau was determined using the linear trapezoidal rule for increasing concentrations and the logarithmic trapezoidal rule for decreasing concentrations. Data for participants while on IV therapy has been presented.

Samples for assessment of PK parameters AUClast and AUC0-tau was done at predose, 1, 2, 3 hours after first orally administered drug and one predose time point anytime from Day 7 to 10. The AUC 0-t and AUC0-tau was determined using the linear trapezoidal rule for increasing concentrations and the logarithmic trapezoidal rule for decreasing concentrations. Data for participants while on oral dose therapy has been presented.

Reduction in susceptibility was defined as a \>=4-fold increase in minimum inhibitory concentration (MIC) or \>=6 millimeter decrease in zone size between an isolate obtained at Baseline and the same pathogen at subsequent visits.

An AE is any untoward medical occurrence in a participant, temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product. An AE can therefore be any unfavorable and unintended sign (including an abnormal laboratory finding), symptom, or disease (new or exacerbated) temporally associated with the use of a medicinal product. An SAE is any untoward medical occurrence that, at any dose results in death, is life-threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or is a congenital anomaly/birth defect, medically significant or all events of possible drug-induced liver injury with hyperbilirubinemia.

SBP and DBP was measured with the participant in a supine or semi-supine position, having rested in that position for at least 10 minutes. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Pulse rate was measured with the participant in a supine or semi-supine position, having rested in that position for at least 10 minutes. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Respiratory rate was measured with the participant in a supine or semi-supine position, having rested in that position for at least 10 minutes. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Body temperature was measured with the participant in a supine or semi-supine position, having rested in that position for at least 10 minutes. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

The 12-lead ECGs was obtained at Day 1, Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28 for corrected QT, using Fridericia formula (QTcF), corrected QT using Bazett's formula (QTcB) and QRS intervals. The number of participants with maximum post-baseline ECG value exceeding the following limits have been reported: QTcB/QTcF interval \> 450 and ≤ 480 millisecond (msec), QTcB/QTcF interval \> 480 and ≤ 500 msec, QTcB/QTcF interval \> 500 msec, QRS interval \< 70 msec and QRS interval \> 120 msec.

Blood samples for assessment of clinical chemistry parameters of ALT, ALP, AST, FSH and GGT was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of clinical chemistry parameters of albumin and total protein was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of clinical chemistry parameters of bilirubin, creatinine, direct bilirubin and urate was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of clinical chemistry parameters of calcium, carbon dioxide, chloride, glucose, magnesium, potassium, sodium and urea was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of clinical chemistry parameter of estimated creatinine clearance was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of clinical chemistry parameter of estradiol was collected at Baseline (Day 1). No post-baseline values were reported.

Blood samples for assessment of hematology parameters of basophils, eosinophils, leukocytes, lymphocytes, monocytes, neutrophils and platelets was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of hematology parameters of EMCHC and hemoglobin was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of hematology parameter of EMCH was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of hematology parameter of EMCV was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of hematology parameter of erythrocyte was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Blood samples for assessment of hematology parameter of hematocrit was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28. Baseline was defined at Day 1. Change from Baseline was calculated by subtracting the post-Baseline value from Baseline value.

Samples for urinalysis assessment was collected at Baseline (Day 1), Day 2, Day 7 to 10, Day 12 to 21 and Day 21 to Day 28 for Glucose, Ketones, Occult Blood, Protein and pH. Participants with abnormal urinalysis result was reported.