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CompletedNCT01544673Updated Apr 30, 2012

Effect of Linezolid on Ex Vivo Neutrophil and Monocyte Function in Healthy Males

A Phase 1 interventional study of linezolid and Placebo in Gram Positive Infection, sponsored by Pfizer. Completed at 1 site in United States. Open to male participants aged 20 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2012-04-30.

Sponsored by Pfizer · Phase 1, Interventional, and Basic science

Phase
Phase 1
Study type
Interventional
Enrollment
18
Allocation
Randomized
Ages
20 Years to 45 Years
Sex
Male
01

Study summary

Results from previous studies have been inconclusive and the effect of linezolid on cytokines remains unclear. This study is designed to evaluate the effect of linezolid on the functionality of white blood cells (neutrophils and monocytes) in healthy subjects.

02

Conditions studied

  • Gram Positive Infection
03

In context

Lead sponsor

Pfizer is the lead sponsor of 3,244 studies on the registry; 139 are open to participants now.

Of its 582 completed or terminated interventional studies of FDA-regulated products, 381 (65%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
20 Years to 45 Years
Sexes eligible
Male
Accepts healthy volunteers
Yes

Inclusion criteria

  • Healthy male subjects between the ages of 20 and 45 years, inclusive (Healthy is defined as no clinically relevant abnormalities identified by a detailed medical history, full physical examination, including blood pressure and pulse rate measurement and clinical laboratory tests).
  • Body Mass Index (BMI) of 17.5 to 30.5 kg/m2; and a total body weight >50 kg (110 lbs).

Exclusion criteria

Exclusion Criteria:

  • Any condition possibly affecting drug absorption (eg, gastrectomy).
  • Subject who had a bacterial/viral infection within 2 weeks prior to the first dose of study medication.
  • Subjects with current or prior neutropenia (eg, \<1.4 x 109 neutrophils /L).
05

Study design

Phase
Phase 1
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
18 participants (actual)

Study arms

  • Active comparator
    Arm A

    Drug: linezolid

  • Placebo comparator
    Arm B

    Drug: Placebo

Interventions

  • Druglinezolid

    600 mg oral tablet twice daily for 4.5 days

    Also known as: Zyvox

  • DrugPlacebo

    500 mg oral placebo twice daily for 4.5 days

06

What researchers measure

Primary outcomes

  1. Change from baseline in phagocytosis of gram-negative bacteria by neutrophils

    Time frame: Baseline, day 4 and day 5

  2. Change from baseline in phagocytosis of gram-negative bacteria by monocytes

    Time frame: Baseline, day 4 and day 5

  3. Change from baseline in interleukin-1 receptor antagonist secretion in response to lipopolysaccharide stimulation

    Time frame: Baseline, day 4 and day 5

  4. Change from baseline in interleukin-1-beta secretion in response to lipopolysaccharide stimulation

    Time frame: Baseline, day 4 and day 5

  5. Change from baseline in interleukin-6 secretion in response to lipopolysaccharide stimulation

    Time frame: Baseline, day 4 and day 5

  6. Change from baseline in interleukin-8 secretion in response to lipopolysaccharide stimulation

    Time frame: Baseline, day 4 and day 5

  7. Change from baseline in tumor necrosis factor alpha secretion in response to lipopolysaccharide stimulation

    Time frame: Baseline, day 4 and day 5

Secondary outcomes

  1. Linezolid peak concentration on day 4

    Time frame: day 4

  2. Linezolid peak concentration on day 5

    Time frame: day 5

  3. Linezolid trough concentration on day 5

    Time frame: day 5

07

Study locations

1 site
  • Pfizer Investigational Site
    New Haven, Connecticut 06511, United States
08

References and documents

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 30, 2012, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT01544673
Lead sponsor
Pfizer
Responsible party
Sponsor
First posted
Mar 6, 2012
Start date
Mar 2012
Primary completion
Apr 2012
Completion
Apr 2012
Last update
Apr 30, 2012

Study contacts

Pfizer CT.gov Call Center
study director · Pfizer

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Apr 2012. You cannot join it, but the record below documents what was studied.

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