Bacterial Infections, Skin Structures and Soft Tissue Infections
Conditions
Brief summary
The purpose of this study is to evaluate the safety and efficacy of omadacycline as compared to linezolid in the treatment of adults with acute bacterial skin and skin structure infections.
Interventions
Injection for IV dosing; Tablets for oral dosing
Infusion solution for IV dosing; Tablets for oral dosing
Sponsors
Study design
Eligibility
Inclusion criteria
* Patients, ages 18 years or older who have signed the informed consent * Has a qualifying skin and skin structure infection * Female patients must not be pregnant at the time of enrollment * Must agree to a reliable method of birth control during the study and for 30 days following the last dose of study drug
Exclusion criteria
* Infections where the outcome is strongly influenced by factors other than protocol-defined treatment and procedures, that require antibacterial treatment for greater than 14 days * Evidence of significant immunological disease * Severe sepsis or septic shock * Has a history of hypersensitivity or allergic reaction to any tetracycline or to linezolid * Has received an investigational drug within past 30 days * Women who are pregnant or nursing
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Early Clinical Response | Screening; 48 to 72 hours after the first dose of test article | Early clinical response is defined as clinical success, which is categorized as survival with at least a 20% reduction of acute bacterial skin and skin structure infection (ABSSSI) primary lesion size compared to Screening measurements, without receiving any rescue antibacterial therapy. An indeterminate classification is used for a response that could not be adequately inferred because the participant was not assessed because they withdrew consent, were lost to follow-up, or other specified reason. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Screening; 7 to 14 days after the last day of therapy | At the PTE Visit the investigator indicated one of the following outcomes relating to the primary infection under study: Clinical Success: participant was alive; the infection was sufficiently resolved such that further antibacterial therapy was not needed. These participants may have had some residual changes related to infection requiring ancillary treatment. Clinical Failure was defined as meeting any of the following criteria: infection required additional treatment with alternative antibacterial therapy; participant received antibacterial therapy between the End-of-Treatment (EOT) Visit and the PTE Visit that may have been effective for the infection under study for a different infection from the one under study; unplanned major surgical intervention for the infection under study between the EOT and PTE Visits; participant died before evaluation. Indeterminate: clinical response to test article could not be adequately inferred. |
| Number of Participants With the Indicated Investigator Assessment of Clinical Response in the Clinically Evaluable-Post Therapy Evaluation (CE-PTE) Population | Screening; 7 to 14 days after the last day of therapy | At the PTE Visit the investigator indicated one of the following outcomes relating to the primary infection under study: Clinical Success: participant was alive; the infection was sufficiently resolved such that further antibacterial therapy was not needed. These participants may have had some residual changes related to infection requiring ancillary treatment. Clinical Failure was defined as meeting any of the following criteria: infection required additional treatment with alternative antibacterial therapy; participant received antibacterial therapy between the EOT Visit and the PTE Visit that may have been effective for the infection under study for a different infection from the one under study; unplanned major surgical intervention for the infection under study between the EOT and PTE Visits; participant died before evaluation. |
| Number of Participants With the Indicated Type of Adverse Event (AE) | 0 to 37 days | An AE is defined as any untoward, undesired, or unplanned event in the form of signs, symptoms, disease, or laboratory or physiologic observations occurring in a person given a test article or in a clinical study. The event does not need to be causally related to the test article or clinical study. A serious adverse event (SAE) is defined as an event that resulted in death, was life-threatening, required hospitalization or prolongation of an existing hospitalization, resulted in a persistent or significant disability or incapacity, resulted in cancer, or resulted in a congenital anomaly or birth defect. A treatment-emergent AE (TEAE) is defined as any AE that newly appeared, increased in frequency, or worsened in severity on or after the initiation of active test article. Vital sign measurements, electrocardiogram findings, and laboratory values classified as adverse events were included in the analysis. Data are presented as the number of participants with at least 1 of the event. |
Countries
Bulgaria, Croatia, Greece, Hungary, Israel, Latvia, Peru, Poland, Romania, South Africa, Spain, Turkey (Türkiye), Ukraine, United States
Participant flow
Recruitment details
The study was designed to enroll adult participants with Acute Bacterial Skin and Skin Structure Infection (ABSSSI) that was known or suspected to be due to a Gram-positive pathogen(s). Randomization was stratified across treatment groups by type of infection (wound infection, cellulitis/erysipelas, and major abscess) and geographic region.
Pre-assignment details
Participants who met inclusion criteria and did not meet exclusion criteria were randomly assigned to a treatment group, and received their first dose of test article within 4 hours after randomization. All participants were expected to present with ABSSSI severe enough to require a minimum of at least 3 days of intravenous treatment.
Participants by arm
| Arm | Count |
|---|---|
| Omadacycline Participants received intravenous (IV) omadacycline 100 milligrams (mg) every 12 hours (q12h) (2 doses), followed by 100 mg IV every 24 hours (q24h) (starting 24 hours after the first dose), with the option to switch to a 300 mg oral administration q24h after a minimum of 3 days (6 doses) of IV treatment (6 overall IV doses because of the blinding). Participants received 4 active doses plus 2 placebo doses to maintain the blind. The total treatment duration was 7 to 14 days. | 323 |
| Linezolid Participants received linezolid 600 mg IV q12h with the option to switch to a 600 mg oral administration q12h after a minimum of 3 days (6 doses) of IV treatment. The total treatment duration was 7 to 14 days. | 322 |
| Total | 645 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Adverse Event | 0 | 1 |
| Overall Study | Death | 1 | 2 |
| Overall Study | Lost to Follow-up | 10 | 18 |
| Overall Study | Missed EOT/PTE Visit | 1 | 2 |
| Overall Study | Physician Decision | 1 | 1 |
| Overall Study | Randomized, but Not Treated | 6 | 4 |
| Overall Study | Withdrawal by Subject | 9 | 4 |
Baseline characteristics
| Characteristic | Omadacycline | Linezolid | Total |
|---|---|---|---|
| Age, Customized 18-45 years | 146 Participants | 154 Participants | 300 Participants |
| Age, Customized >45-65 years | 141 Participants | 136 Participants | 277 Participants |
| Age, Customized >65 years | 36 Participants | 32 Participants | 68 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 7 Participants | 5 Participants | 12 Participants |
| Race (NIH/OMB) Asian | 1 Participants | 2 Participants | 3 Participants |
| Race (NIH/OMB) Black or African American | 16 Participants | 8 Participants | 24 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 1 Participants | 3 Participants | 4 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 4 Participants | 4 Participants | 8 Participants |
| Race (NIH/OMB) White | 294 Participants | 300 Participants | 594 Participants |
| Sex: Female, Male Female | 120 Participants | 109 Participants | 229 Participants |
| Sex: Female, Male Male | 203 Participants | 213 Participants | 416 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 1 / 323 | 2 / 322 |
| other Total, other adverse events | 104 / 323 | 101 / 322 |
| serious Total, serious adverse events | 12 / 323 | 8 / 322 |
Outcome results
Number of Participants With Early Clinical Response
Early clinical response is defined as clinical success, which is categorized as survival with at least a 20% reduction of acute bacterial skin and skin structure infection (ABSSSI) primary lesion size compared to Screening measurements, without receiving any rescue antibacterial therapy. An indeterminate classification is used for a response that could not be adequately inferred because the participant was not assessed because they withdrew consent, were lost to follow-up, or other specified reason.
Time frame: Screening; 48 to 72 hours after the first dose of test article
Population: Modified Intent-to-Treat (mITT) Population: all randomized participants without a baseline sole Gram-negative ABSSSI pathogen
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Omadacycline | Number of Participants With Early Clinical Response | Clinical success | 268 Participants |
| Omadacycline | Number of Participants With Early Clinical Response | Clinical failure | 23 Participants |
| Omadacycline | Number of Participants With Early Clinical Response | Indeterminate | 25 Participants |
| Linezolid | Number of Participants With Early Clinical Response | Clinical success | 266 Participants |
| Linezolid | Number of Participants With Early Clinical Response | Clinical failure | 19 Participants |
| Linezolid | Number of Participants With Early Clinical Response | Indeterminate | 26 Participants |
Number of Participants With the Indicated Investigator Assessment of Clinical Response in the Clinically Evaluable-Post Therapy Evaluation (CE-PTE) Population
At the PTE Visit the investigator indicated one of the following outcomes relating to the primary infection under study: Clinical Success: participant was alive; the infection was sufficiently resolved such that further antibacterial therapy was not needed. These participants may have had some residual changes related to infection requiring ancillary treatment. Clinical Failure was defined as meeting any of the following criteria: infection required additional treatment with alternative antibacterial therapy; participant received antibacterial therapy between the EOT Visit and the PTE Visit that may have been effective for the infection under study for a different infection from the one under study; unplanned major surgical intervention for the infection under study between the EOT and PTE Visits; participant died before evaluation.
Time frame: Screening; 7 to 14 days after the last day of therapy
Population: CE-PTE Population: all participants in the mITT Population meeting additional pre-defined criteria
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Omadacycline | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the Clinically Evaluable-Post Therapy Evaluation (CE-PTE) Population | Clinical success | 259 Participants |
| Omadacycline | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the Clinically Evaluable-Post Therapy Evaluation (CE-PTE) Population | Clinical failure | 10 Participants |
| Linezolid | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the Clinically Evaluable-Post Therapy Evaluation (CE-PTE) Population | Clinical success | 243 Participants |
| Linezolid | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the Clinically Evaluable-Post Therapy Evaluation (CE-PTE) Population | Clinical failure | 17 Participants |
Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit
At the PTE Visit the investigator indicated one of the following outcomes relating to the primary infection under study: Clinical Success: participant was alive; the infection was sufficiently resolved such that further antibacterial therapy was not needed. These participants may have had some residual changes related to infection requiring ancillary treatment. Clinical Failure was defined as meeting any of the following criteria: infection required additional treatment with alternative antibacterial therapy; participant received antibacterial therapy between the End-of-Treatment (EOT) Visit and the PTE Visit that may have been effective for the infection under study for a different infection from the one under study; unplanned major surgical intervention for the infection under study between the EOT and PTE Visits; participant died before evaluation. Indeterminate: clinical response to test article could not be adequately inferred.
Time frame: Screening; 7 to 14 days after the last day of therapy
Population: mITT Population
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Omadacycline | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Clinical success | 272 Participants |
| Omadacycline | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Clinical failure | 20 Participants |
| Omadacycline | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Indeterminate | 24 Participants |
| Linezolid | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Clinical success | 260 Participants |
| Linezolid | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Clinical failure | 27 Participants |
| Linezolid | Number of Participants With the Indicated Investigator Assessment of Clinical Response in the mITT Population at the Post Therapy Evaluation (PTE) Visit | Indeterminate | 24 Participants |
Number of Participants With the Indicated Type of Adverse Event (AE)
An AE is defined as any untoward, undesired, or unplanned event in the form of signs, symptoms, disease, or laboratory or physiologic observations occurring in a person given a test article or in a clinical study. The event does not need to be causally related to the test article or clinical study. A serious adverse event (SAE) is defined as an event that resulted in death, was life-threatening, required hospitalization or prolongation of an existing hospitalization, resulted in a persistent or significant disability or incapacity, resulted in cancer, or resulted in a congenital anomaly or birth defect. A treatment-emergent AE (TEAE) is defined as any AE that newly appeared, increased in frequency, or worsened in severity on or after the initiation of active test article. Vital sign measurements, electrocardiogram findings, and laboratory values classified as adverse events were included in the analysis. Data are presented as the number of participants with at least 1 of the event.
Time frame: 0 to 37 days
Population: Safety Population: all randomized participants who received test article
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | AE | 158 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE | 156 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | Drug-releated AE | 58 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | Severe TEAE | 6 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | Serious TEAE | 12 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | Drug-related serious TEAE | 0 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | Serious TEAE leading to death | 1 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE leading to premature drug discontinuation | 6 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE leading to premature discontinuation of study | 6 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE leading to dose interruption | 2 Participants |
| Omadacycline | Number of Participants With the Indicated Type of Adverse Event (AE) | Serious TEAEs leading to drug discontinuation | 3 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | Serious TEAEs leading to drug discontinuation | 3 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | AE | 157 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | Serious TEAE leading to death | 2 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE leading to dose interruption | 0 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | Drug-releated AE | 59 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE leading to premature drug discontinuation | 7 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | Severe TEAE | 10 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE | 147 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | Serious TEAE | 8 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | TEAE leading to premature discontinuation of study | 7 Participants |
| Linezolid | Number of Participants With the Indicated Type of Adverse Event (AE) | Drug-related serious TEAE | 0 Participants |