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Uncomplicated Skin and Soft Tissue Infections Caused by Community-Associated Methicillin-Resistant Staphylococcus Aureus

Randomized, Double-Blind Trial of Clindamycin, Trimethoprim-Sulfamethoxazole, or Placebo for Uncomplicated Skin and Soft Tissue Infections Caused by Community-Associated Methicillin-Resistant Staphylococcus Aureus

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT00730028
Enrollment
1310
Registered
2008-08-08
Start date
2009-04-30
Completion date
2015-02-28
Last updated
2016-03-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Staphylococcal Infection

Keywords

Methicillin-resistant Staphylococcus aureus (MRSA), cellulitis, abscess, children, elderly

Brief summary

The purpose of this clinical trial is to evaluate 2 different antibiotics, drugs that fight bacteria, \[clindamycin (CLINDA) and trimethoprim-sulfamethoxazole (TMP-SMX)\] and wound care for the outpatient management of uncomplicated skin and soft tissue infections (uSSTIs) in children and adults. The study will occur in areas where community associated methicillin-resistant Staphylococcus (S.) aureus are common. S. aureus is a type of bacteria. A total of 1310 volunteers, greater than or equal to 6 months of age and adults 85 years or younger, non-immunocompromised, with uSSTIs (in particular abscess and/or cellulitis) will be enrolled in this study. Subjects will be treated with one of the following: CLINDA, TMP-SMX, or placebo (contains no medication). Volunteers will be grouped based on the presence of cellulitis or abscess, whether the abscess can be surgically drained, and its size. The subject participation duration for this study is about 6 weeks.

Detailed description

Clinical practice in the treatment of community-onset skin and soft tissue infections (SSTI) has not kept pace with the emergence of methicillin-resistant Staphylococcus aureus (MRSA) in the community. This clinical trial will evaluate clindamycin (CLINDA) and trimethoprim-sulfamethoxazole (TMP-SMX) and wound care for the outpatient management of uncomplicated skin and soft tissue infection (uSSTI) in 3 metropolitan areas, Chicago, Los Angeles, and San Francisco, cities with high prevalence of community acquired (CA)-MRSA. This is a phase IIb multicenter, stratified, randomized, double-blind trial in which enrolled subjects with abscess or cellulitis will be treated with CLINDA, TMP-SMX, or placebo. Participants will include 1310 non-immunocompromised out-patients age 6 months to 85 years with SSTIs not requiring hospital admission. Subjects will undergo a screening/baseline evaluation, including determination of presence and size of abscess and/or presence of cellulitis. Subjects will then be randomized to receive treatment with either CLINDA, TMP-SMX, or placebo depending on whether they have: a larger drainable abscess, defined as greater than 5 cm in diameter in adults and as greater than 3 cm in diameter for ages 6-11 months, greater than 4 cm for ages 1-8 years, and greater than 5 cm for age 9 years and older; a limited drainable abscess, defined as less than or equal to 5 cm for adults and as less than or equal to 3 cm for ages 6-11 months, less than or equal to 4 cm for ages 1-8 years, and less than or equal to 5 cm for age 9 years and older; or cellulitis or erysipelas only. If the diameter of the abscess greater than 5 cm (smaller for children depending on age) or 2 or more sites of skin infection are present the subject will be randomized (1:1) to 10 days of therapy with TMP-SMX or CLINDA. If the diameter of the abscess less than or equal to 5 cm (smaller for children depending on age) then the subject will be randomized (1:1:1) to TMP-SMX, CLINDA or placebo for 10 days. Subjects with cellulitis or erysipelas only will be randomized (1:1) to TMP-SMX or CLINDA for 10 days. Subjects will be provided study drug, instructed in its use, and scheduled for 4 follow-up visits including: wound check (24-48 hours after enrollment); end of therapy (48 hours after completion of therapy); test of cure (7-10 days after completion of therapy); and a final visit at one month after completion of therapy. The primary objectives of this study are: to compare the cure rate of CLINDA to that of TMP-SMX for the treatment of patients with cellulitis or larger abscess at the Test of Cure (TOC) visit and to compare the cure rate of CLINDA, TMP-SMX, and placebo, each in conjunction with surgical drainage for the treatment of subjects with limited abscess at the TOC visit.

Interventions

DRUGTrimethoprim-sulfamethoxazole

Trimethoprim-sulfamethoxazole (TMP-SMX) will be administered orally at a dose of 160 mg TMP and 800 mg SMX (as 2 single strength over encapsulated tablets) twice daily (adult or child \> 40 kg dose) or 8-10 mg TMP, 40-50 mg SMX per kg daily, divided into 2 daily doses (child \< 40 kg dose). Study drug will be administered for 10 days.

OTHERPlacebo

Placebo capsules will be identical in appearance to the CLINDA and TMP-SMX. Administered 3 times daily for 10 days.

DRUGClindamycin

CLINDA (adult dose of 300 mg three times daily; pediatric dose of 25-30 mg/kg/day divided three times daily up to a maximum dose of 900 mg/day). Study drug will be administered for 10 days.

Sponsors

National Institute of Allergy and Infectious Diseases (NIAID)
Lead SponsorNIH

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
6 Months to 85 Years
Healthy volunteers
No

Inclusion criteria

* Age 6 months to 85 years. * Able to complete the informed consent process or, if a minor, a parent or guardian who is able to complete the informed consent process; an assent form also will be completed for children age 7 and older. * Willing and able to complete the study protocol, study-related activities, and visits. * Diagnosis of uncomplicated skin and soft tissue infection (uSSTI), either cellulitis (defined as an inflammation of skin and associated skin structures) or abscess (defined as a circumscribed collection of pus), evidenced by at least 2 of the following localized signs or symptoms on the skin for at least 24 hours: 1. Erythema 2. Swelling or induration 3. Local warmth 4. Purulent drainage 5. Tenderness to palpation or pain * Able to take oral antibiotic therapy, either in pill or suspension form.

Exclusion criteria

* Hospital in-patient. * Hospitalization within the prior 14 days. * Residence in a long-term skilled nursing facility. * Requirement for hospitalization for skin infection or other condition. * Previous enrollment in this protocol. * Participation in another clinical trial within the previous 30 days. * Superficial skin infection only, including: 1. Impetigo 2. Ecthyma 3. Folliculitis 4. Infections that have a high cure rate after surgical incision alone (such as isolated furunculosis) or after topical or local measures * Unstable psychiatric or psychological condition rendering the subject unlikely to be cooperative or to complete study requirements. * Active drug or alcohol use or dependence that, in the opinion of the site investigator, would interfere with the adherence or subject compliance with study requirements. * Systolic blood pressure \> 180 mm Hg. * Systolic blood pressure (SBP) less than an age-specific critical value: 1. Age 6 - 11 months: \< 70 mm Hg 2. Age 1 to 8 years: \< 80 mm Hg 3. Age 9 to 17 years: \< 90 mm Hg 4. Age greater than or equal to 18 years: \< 90 mm Hg * Heart rate less than 45 beats per minute (BPM). * Heart rate greater than an age-specific critical value: 1. Age 6 - 11 months: \> 140 BPM 2. Age 1 to 8 years: \> 120 BPM 3. Age 9 to 17 years: \> 120 BPM 4. Age greater than or equal to 18 years: \> 120 BPM. * Oral temperature (or equivalent rectal, tympanic membrane, axillary) less than 35.5 degrees Celsius (95.9 degrees Fahrenheit). * Oral temperature (or equivalent rectal, tympanic membrane, axillary) greater than age-specific critical value: 1. Age 6 - 11 months: \> 38.0 degrees Celsius (100.4 degrees Fahrenheit) 2. Age 1 to 8 years: \> 38.5 degrees Celsius (101.3 degrees Fahrenheit) 3. Age 9 to 17 years: \> 38.5 degrees Celsius (101.3 degrees Fahrenheit) 4. Age greater than or equal to 18 years: \> 38.5 degrees Celsius (101.3 degrees Fahrenheit). * Documented human or witnessed animal bite in the past 30 days at the site of infection. * Systemic antibacterial therapy with antistaphylococcal activity within the prior 14 days. * The following concomitant medications: warfarin, phenytoin, methotrexate, rosiglitazone or sulfonylureas and systemically administered antibacterial agents with activity against staphylococci. * Diagnosed or suspected disseminated or severe Staphylococcus aureus or group A streptococcal (GAS) infection, including lymphangitic spread of skin infection, septicemia, bacteremia, pneumonia, endocarditis, osteomyelitis, septic arthritis, gangrene, necrotizing fasciitis, myositis, or other serious infections. * Infection at an anatomical skin site requiring specialized management or specialized antimicrobial therapy, including: 1. Periauricular or orbital infection 2. Perirectal infection 3. Suspected deep space infection of the hand or foot 4. Genital infection 5. Mastitis 6. Bursitis * Radiographic evidence or suspicion of gas in the tissue or foreign body infection (note: radiography is not required for screening and can be performed at the discretion of the treating physician). * Gastrointestinal symptoms such as nausea, vomiting, or diarrhea of a severity that would preclude consumption of oral antibiotics. * Hypersensitivity or history of allergic reaction to study drug. * History of glucose-6-phosphate dehydrogenase (G6PD) deficiency. * Third trimester pregnancy: pregnant women must have gestational age estimated by an objective means, e.g. ultrasound, fundal height, and women who are within 4 weeks of the third trimester of pregnancy, defined as week 27 of pregnancy, are not eligible. * Currently breast feeding. * Severe or morbid obesity with a body mass index (BMI) \>40 kg/m\^2. * Complicated skin or soft tissue infection, such as: 1. Catheter or catheter site infection within 30 days of placement 2. Surgical site infection 3. Known or suspected prosthetic device infection 4. Suspected Gram-negative or anaerobic pathogen 5. Unusual exposure history (e.g., underwater injury, fish-tank exposure, heavy soil exposure, etc) 6. Infection at the site of an area of underlying skin disease such as chronic eczema, psoriasis, atopic dermatitis, or chronic venous stasis * History of underlying immunocompromising condition or immunodeficiency, for example: 1. Diabetes mellitus 2. Chronic renal failure, creatinine clearance \<30 ml/min 3. Renal dialysis within the past 180 days 4. Human immunodeficiency virus (HIV)-positive with either cluster of differentiation (CD)4 count \<200 or \<4 percent CD4 in the past 180 days or HIV-positive and no documented CD4 count in the past 4 months 5. Organ or bone marrow transplantation (ever), immunosuppressive therapy within the past 180 days, severe liver disease 6. Other serious underlying disease, as determined by the treating physician or the investigator

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.Test of cure (TOC) (7-10 days after completion of therapy)Clinical failure is defined as the occurence of any of the following: 1. Lack of resolution at the Test of Cure (TOC) visit in any or all of the following: erythema, tenderness, purulent drainage, swelling, and local warmth. Erythema or tenderness that was considered due the surgical therapy itself (incision and drainage), was not considered to be indicative of clinical failure. 2. Occurrence of a SSTI at another site other than the site(s) under study. 3. Intolerance of study medication or a treatment-limiting adverse reaction necessitating discontinuation of study drug within the first 48 hours. 4. Administration of other antimicrobial therapy for treatment of a SSTI at any time through the TOC visit. 5. Unplanned surgical procedure for the infection under study at any time through the TOC visit. 6. Hospitalization for treatment of active or invasive infection at any time through the TOC visit.
Percentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.Test of cure (TOC) (7-10 days after completion of therapy)Clinical failure is defined as the occurence of any of the following: 1. Lack of resolution at the Test of Cure (TOC) visit in any or all of the following: erythema, tenderness, purulent drainage, swelling, and local warmth. Erythema or tenderness that was considered due the surgical therapy itself (incision and drainage), was not considered to be indicative of clinical failure. 2. Occurrence of a SSTI at another site other than the site(s) under study. 3. Intolerance of study medication or a treatment-limiting adverse reaction necessitating discontinuation of study drug within the first 48 hours. 4. Administration of other antimicrobial therapy for treatment of a SSTI at any time through the TOC visit. 5. Unplanned surgical procedure for the infection under study at any time through the TOC visit. 6. Hospitalization for treatment of active or invasive infection at any time through the TOC visit.

Secondary

MeasureTime frameDescription
Percentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.EOT visit within 48 hours of completion of therapyMeasures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure.
Percentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.EOT visit within 48 hours of completion of therapyMeasures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure.
Number of Participants Reporting Adverse Events.End of Treatment (EOT) (48 hours after completion of therapy); Test of Cure (TOC) (7-10 days after completion of therapy); One Month Follow-up Visit (OMFU)Subjects were issued a Memory Aid to record symptoms for 10 days post product administration. At study visits, the staff reviewed the memory aid and elicited as much information as possible about any reported symptoms. Occurrence of adverse events was solicited in the memory aid and during study visits. Reported symptoms, both solicited and unsolicited, were recorded as Adverse Events.
Percentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.OMFU visitMeasures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure, with one addition. At the OMFU, relapse (the return of the original infection after initial improvement) or recurrence (return of skin infection at original site after cure of original infection) of SSTI was scored as clinical failure.
Percentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.OMFU visitMeasures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure, with one addition. At the OMFU, relapse (the return of the original infection after initial improvement) or recurrence (return of skin infection at original site after cure of original infection) of SSTI was scored as clinical failure.
Number of Participants Reporting Adverse Events That Are Treatment Limiting.End of Treatment (EOT) (48 hours after completion of therapy); Test of Cure (TOC) (7-10 days after completion of therapy); One Month Follow-up Visit (OMFU)Participants were issued a Memory Aid to record symptoms for 10 days post product administration. At study visits, the staff reviewed the memory aid and elicited as much information as possible about any reported symptoms. Occurrence of adverse events was solicited in the memory aid and during study visits. Reported symptoms, both solicited and unsolicited, were recorded as Adverse Events. For these results, adverse events that resulted in discontinuation of study treatment for the participant were considered treatment limiting.

Countries

United States

Participant flow

Recruitment details

Participants were non-immunocompromised out-patients age 6 months to 85 years with SSTIs not requiring hospital admission were recruited across 6 sites from communities with an anticipated prevalence of community-associated MRSA. Participants were enrolled between April 13, 2009 and January 13, 2015

Participants by arm

ArmCount
Cellulitis or Larger Abscess - Clindamycin
Participants with cellulitis only or abscess \> 5 cm in diameter in adults and children age 9 years and older, \> 4 cm in diameter in children age 1 to 8 years, or \> 3 cm in diameter in children age 6 to 12 months, or with 2 or more sites of skin infection were treated with CLINDA300 mg three times daily for adults; 25-30 mg/kg/day divided three times daily for children.
264
Cellulitis or Larger Abscess - TMP-SMX
Participants with cellulitis only or abscess \> 5 cm in diameter in adults and children age 9 years and older, \> 4 cm in diameter in children age 1 to 8 years, or \> 3 cm in diameter in children age 6 to 12 months, or with 2 or more sites of skin infection were treated with TMP-SMX 160/800 mg twice daily for adults; 8-10 mg/kg of TMP, 40-50 mg/kg of SMX twice daily for children.
260
Limited Abscess - Clindamycin
Participants with limited abscess with or without cellulitis less than or equal to 5 cm in diameter in adults and children age 9 years and older, \< 4 cm in diameter in children age 1 to 8 years, or \< 3 cm in diameter in children age 6 to 12 months were treated with CLINDA300 mg three times daily for adults; 25-30 mg/kg/day divided three times daily for children.
266
Limited Abscess - TMP-SMX
Participants with limited abscess with or without cellulitis less than or equal to 5 cm in diameter in adults and children age 9 years and older, \< 4 cm in diameter in children age 1 to 8 years, or \< 3 cm in diameter in children age 6 to 12 months were treated with TMP-SMX 160/800 mg twice daily for adults; 8-10 mg/kg of TMP, 40-50 mg/kg of SMX twice daily for children.
263
Limited Abscess - Placebo
Participants with limited abscess with or without cellulitis less than or equal to 5 cm in diameter in adults and children age 9 years and older, \< 4 cm in diameter in children age 1 to 8 years, or \< 3 cm in diameter in children age 6 to 12 months were treated with placebo three times daily.
257
Total1,310

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003FG004
Overall StudyAdverse Event2326162043
Overall StudyLost to Follow-up1326222625
Overall StudyPhysician Decision33232
Overall StudyProtocol Violation61120
Overall StudyRandomization Error10002
Overall StudyTreatment Failure55001
Overall StudyWithdrawal by Subject95459

Baseline characteristics

CharacteristicCellulitis or Larger Abscess - TMP-SMXLimited Abscess - ClindamycinLimited Abscess - TMP-SMXCellulitis or Larger Abscess - ClindamycinLimited Abscess - PlaceboTotal
Age, Categorical
<=18 years
74 Participants101 Participants91 Participants81 Participants89 Participants436 Participants
Age, Categorical
>=65 years
2 Participants1 Participants3 Participants2 Participants2 Participants10 Participants
Age, Categorical
Between 18 and 65 years
184 Participants164 Participants169 Participants181 Participants166 Participants864 Participants
Age, Continuous27.5 years
STANDARD_DEVIATION 16.9
24.8 years
STANDARD_DEVIATION 17.8
25.6 years
STANDARD_DEVIATION 18.1
26.8 years
STANDARD_DEVIATION 17.2
26.2 years
STANDARD_DEVIATION 18.7
27.1 years
STANDARD_DEVIATION 17
Region of Enrollment
United States
260 participants266 participants263 participants264 participants257 participants1310 participants
Sex: Female, Male
Female
121 Participants126 Participants111 Participants129 Participants101 Participants588 Participants
Sex: Female, Male
Male
139 Participants140 Participants152 Participants135 Participants156 Participants722 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
EG004
affected / at risk
deaths
Total, all-cause mortality
— / —— / —— / —— / —— / —
other
Total, other adverse events
59 / 26472 / 26061 / 26652 / 26360 / 257
serious
Total, serious adverse events
4 / 2645 / 2600 / 2666 / 2632 / 257

Outcome results

Primary

Percentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.

Clinical failure is defined as the occurence of any of the following: 1. Lack of resolution at the Test of Cure (TOC) visit in any or all of the following: erythema, tenderness, purulent drainage, swelling, and local warmth. Erythema or tenderness that was considered due the surgical therapy itself (incision and drainage), was not considered to be indicative of clinical failure. 2. Occurrence of a SSTI at another site other than the site(s) under study. 3. Intolerance of study medication or a treatment-limiting adverse reaction necessitating discontinuation of study drug within the first 48 hours. 4. Administration of other antimicrobial therapy for treatment of a SSTI at any time through the TOC visit. 5. Unplanned surgical procedure for the infection under study at any time through the TOC visit. 6. Hospitalization for treatment of active or invasive infection at any time through the TOC visit.

Time frame: Test of cure (TOC) (7-10 days after completion of therapy)

Population: The efficacy evaluable population was comprised of all participants who had outcomes determined at the Test of Cure (TOC) visit.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.89.5 percentage of participants
Cellulitis or Larger Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.88.2 percentage of participants
Limited Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.92.9 percentage of participants
Limited Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.92.7 percentage of participants
Limited Abscess - PlaceboPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Evaluable Population.80.5 percentage of participants
Comparison: Primary null hypothesis: Clindamycin and TMP-SMX have equal rates of cure in the treatment of cellulitis/larger abscess at the Test of Cure (TOC) visit.p-value: 0.768895% CI: [-7.6, 5.1]Fisher Exact
Comparison: Primary null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess at the TOC visit.p-value: 195% CI: [-5.4, 5.1]Fisher Exact
Comparison: Primary null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess at the TOC visit.p-value: <0.000195% CI: [-19.2, -5.6]Fisher Exact
Comparison: Primary null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess at the TOC visit.p-value: 0.000295% CI: [-19.1, -5.4]Fisher Exact
Primary

Percentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.

Clinical failure is defined as the occurence of any of the following: 1. Lack of resolution at the Test of Cure (TOC) visit in any or all of the following: erythema, tenderness, purulent drainage, swelling, and local warmth. Erythema or tenderness that was considered due the surgical therapy itself (incision and drainage), was not considered to be indicative of clinical failure. 2. Occurrence of a SSTI at another site other than the site(s) under study. 3. Intolerance of study medication or a treatment-limiting adverse reaction necessitating discontinuation of study drug within the first 48 hours. 4. Administration of other antimicrobial therapy for treatment of a SSTI at any time through the TOC visit. 5. Unplanned surgical procedure for the infection under study at any time through the TOC visit. 6. Hospitalization for treatment of active or invasive infection at any time through the TOC visit.

Time frame: Test of cure (TOC) (7-10 days after completion of therapy)

Population: The ITT population was comprised of all participants enrolled in the trial.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.80.3 percentage of participants
Cellulitis or Larger Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.77.7 percentage of participants
Limited Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.83.1 percentage of participants
Limited Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.81.7 percentage of participants
Limited Abscess - PlaceboPercentage of Participants Achieving Clinical Cure, Defined as Absence of Clinical Failure, in the Intent-to-Treat (ITT) Population.68.9 percentage of participants
Comparison: Primary null hypothesis: Clindamycin and TMP-SMX have equal rates of cure in the treatment of cellulitis/larger abscess at the Test of Cure (TOC) visit.p-value: 0.5295% CI: [-10.2, 4.9]Fisher Exact
Comparison: Primary null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess at the TOC visit.p-value: 0.732495% CI: [-8.4, 5.7]Fisher Exact
Comparison: Primary null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess at the TOC visit.p-value: 0.000195% CI: [-22, -6.4]Fisher Exact
Comparison: Primary null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess at the TOC visit.p-value: 0.000895% CI: [-20.8, -5]Fisher Exact
Secondary

Number of Participants Reporting Adverse Events.

Subjects were issued a Memory Aid to record symptoms for 10 days post product administration. At study visits, the staff reviewed the memory aid and elicited as much information as possible about any reported symptoms. Occurrence of adverse events was solicited in the memory aid and during study visits. Reported symptoms, both solicited and unsolicited, were recorded as Adverse Events.

Time frame: End of Treatment (EOT) (48 hours after completion of therapy); Test of Cure (TOC) (7-10 days after completion of therapy); One Month Follow-up Visit (OMFU)

Population: Participants who received treatment with either clindamycin or TMP/SMX in the cellulitis or larger abscess group and participants who received treatment with either clindamycin, TMP/SMX, or placebo in the limited abscess group.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinNumber of Participants Reporting Adverse Events.116 participants
Cellulitis or Larger Abscess - TMP-SMXNumber of Participants Reporting Adverse Events.132 participants
Limited Abscess - ClindamycinNumber of Participants Reporting Adverse Events.119 participants
Limited Abscess - TMP-SMXNumber of Participants Reporting Adverse Events.94 participants
Limited Abscess - PlaceboNumber of Participants Reporting Adverse Events.119 participants
Secondary

Number of Participants Reporting Adverse Events That Are Treatment Limiting.

Participants were issued a Memory Aid to record symptoms for 10 days post product administration. At study visits, the staff reviewed the memory aid and elicited as much information as possible about any reported symptoms. Occurrence of adverse events was solicited in the memory aid and during study visits. Reported symptoms, both solicited and unsolicited, were recorded as Adverse Events. For these results, adverse events that resulted in discontinuation of study treatment for the participant were considered treatment limiting.

Time frame: End of Treatment (EOT) (48 hours after completion of therapy); Test of Cure (TOC) (7-10 days after completion of therapy); One Month Follow-up Visit (OMFU)

Population: Participants who received treatment with either clindamycin or TMP/SMX in the cellulitis or larger abscess group and participants who received treatment with either clindamycin, TMP/SMX, or placebo in the limited abscess group.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinNumber of Participants Reporting Adverse Events That Are Treatment Limiting.1 participants
Cellulitis or Larger Abscess - TMP-SMXNumber of Participants Reporting Adverse Events That Are Treatment Limiting.0 participants
Limited Abscess - ClindamycinNumber of Participants Reporting Adverse Events That Are Treatment Limiting.6 participants
Limited Abscess - TMP-SMXNumber of Participants Reporting Adverse Events That Are Treatment Limiting.3 participants
Limited Abscess - PlaceboNumber of Participants Reporting Adverse Events That Are Treatment Limiting.4 participants
Secondary

Percentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.

Measures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure.

Time frame: EOT visit within 48 hours of completion of therapy

Population: The efficacy evaluable population was comprised of all participants who had outcomes determined at the EOT visit.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.89.2 percentage of participants
Cellulitis or Larger Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.88.3 percentage of participants
Limited Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.90.9 percentage of participants
Limited Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.94.2 percentage of participants
Limited Abscess - PlaceboPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Evaluable Population.84.9 percentage of participants
Comparison: Null hypothesis: Clindamycin and TMP-SMX have equal rates of cure in the treatment of cellulitis/larger abscess.p-value: 0.770795% CI: [-7.1, 5.3]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.214195% CI: [-2, 8.5]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.059395% CI: [-12.4, 0.5]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.001795% CI: [-15.3, -3.1]Fisher Exact
Secondary

Percentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.

Measures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure.

Time frame: EOT visit within 48 hours of completion of therapy

Population: All participants enrolled in the trial.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.81.1 percentage of participants
Cellulitis or Larger Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.75.4 percentage of participants
Limited Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.78.9 percentage of participants
Limited Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.79.8 percentage of participants
Limited Abscess - PlaceboPercentage of Participants Achieving Clinical Cure at the End of Treatment (EOT) Visit for the Intent-to-Treat (ITT) Population.72.4 percentage of participants
Comparison: Null hypothesis: Clindamycin and TMP-SMX have equal rates of cure in the treatment of cellulitis/larger abscess.p-value: 0.138195% CI: [-13.1, 1.8]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.830295% CI: [-6.4, 8.2]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.083895% CI: [-14.3, 1.1]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.050795% CI: [-15.2, 0.2]Fisher Exact
Secondary

Percentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.

Measures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure, with one addition. At the OMFU, relapse (the return of the original infection after initial improvement) or recurrence (return of skin infection at original site after cure of original infection) of SSTI was scored as clinical failure.

Time frame: OMFU visit

Population: The efficacy evaluable population was comprised of all participants who had outcomes determined at the OMFU visit.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.83.9 percentage of participants
Cellulitis or Larger Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.78.2 percentage of participants
Limited Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.89.3 percentage of participants
Limited Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.85.0 percentage of participants
Limited Abscess - PlaceboPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Evaluable Population.73.9 percentage of participants
Comparison: Null hypothesis: Clindamycin and TMP-SMX have equal rates of cure in the treatment of cellulitis/larger abscess.p-value: 0.150595% CI: [-13.3, 1.9]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.166695% CI: [-10.9, 2.2]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: <0.000195% CI: [-23, -8]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.004695% CI: [-19, -3.2]Fisher Exact
Secondary

Percentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.

Measures of clinical cure and clinical failure are the same as those defined for the primary efficacy outcome measure, with one addition. At the OMFU, relapse (the return of the original infection after initial improvement) or recurrence (return of skin infection at original site after cure of original infection) of SSTI was scored as clinical failure.

Time frame: OMFU visit

Population: All participants enrolled in the trial.

ArmMeasureValue (NUMBER)
Cellulitis or Larger Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.73.1 percentage of participants
Cellulitis or Larger Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.67.7 percentage of participants
Limited Abscess - ClindamycinPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.78.6 percentage of participants
Limited Abscess - TMP-SMXPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.73.0 percentage of participants
Limited Abscess - PlaceboPercentage of Participants Achieving Clinical Cure at the One Month Follow-up (OMFU) Visit for the Intent-to-Treat (ITT) Population.62.6 percentage of participants
Comparison: Null hypothesis: Clindamycin and TMP-SMX have equal rates of cure in the treatment of cellulitis/larger abscess.p-value: 0.181595% CI: [-13.6, 2.8]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.155295% CI: [-13.2, 2.1]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: <0.000195% CI: [-24, -7.8]Fisher Exact
Comparison: Null hypothesis: After successful surgical drainage, placebo, Clindamycin, and TMP-SMX have equal rates of cure in the treatment of limited abscess.p-value: 0.014595% CI: [-18.7, -2]Fisher Exact

Source: ClinicalTrials.gov · Data processed: Mar 5, 2026