A Phase 4 interventional study of Zoliflodacin and Placebo in Testicular Abnominalies, sponsored by Global Antibiotics Research and Development Partnership. Not yet recruiting at 2 sites in 2 countries. Open to male participants aged 18 Years to 45 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-06-10.
Sponsored by Global Antibiotics Research and Development Partnership · Phase 4, Interventional, and Screening
This study is a randomized, double-blind, placebo-controlled clinical trial to evaluate the effect of zoliflodacin on testicular function in healthy adult men. Participants will be screened within 21 days before randomization (Day 1), including collection of 2 semen samples (each collected after a ≥48 hours and ≤7 days ejaculation-free period). Approximately 220 participants who provide written informed consent and meet all inclusion and no exclusion criteria will be enrolled and randomized in a 1:1 fashion to receive a single dose of either zoliflodacin 3 g or placebo administered as an oral suspension on Day 1.
Each participant will be contacted by telephone at Week 1 and at Week 7 post dosing to review adverse events (AEs), concomitant medications and procedures, and genitourinary symptoms.
Each participant will return to the trial site at Week 13 for collection of 2 semen samples (each collected after a ≥48 hours and ≤7 days ejaculation-free period). A serum sample will also be collected for hormone testing (luteinizing hormone [LH], follicle-stimulating hormone [FSH], and total testosterone) at Week 13 to support biological interpretation of any decrease in sperm concentration.
Participants who do not have a ≥50% decrease from baseline in sperm concentration at Week 13 will complete the trial at Week 13 (end of trial). Participants with a ≥50% decrease from baseline in sperm concentration at Week 13 will return to the trial site at Week 26 for collection of 2 semen samples (independent ejaculates, each collected after a ≥48 hours and ≤7 days ejaculation-free period) for evaluation of the reversibility of the Week 13 finding, following completion of a one additional spermatogenic cycle post completion of dosing/drug exposure (FDA 2018) (end of trial).
All Adverse Events, medications, and procedures will be recorded from the signing of the informed consent form (ICF) through the end-of-trial visit (Week 13, Week 26, or Early Termination)
Global Antibiotics Research and Development Partnership is the lead sponsor of 3 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Semen parameters for each semen sample collected during Screening meeting the following criteria (WHO 2021):
Exclusion Criteria:
Use within 13 weeks before Screening of or anticipated need during the trial for a medication known to affect spermatogenesis or reproductive hormone regulation including, but not limited to, the following medications:
Drug: Zoliflodacin
Drug: Placebo
Oral suspension of Zoliflodacin 3g
Oral suspension of matching placebo
Sperm concentration
Percentage of participants with a ≥50% decrease from baseline in sperm concentration (million/mL) at Week 13
Time frame: Week 13 (and potentially week 26)
Semen Volume
Change in semen volume (in mL)
Time frame: At baseline and week 13
Sperm count
Total sperm count per ejaculate (million)
Time frame: At Baseline and week 13
Progressive mobility
Sperm exhibiting active forward movement (μm/s)
Time frame: At Baseline and Week 13
Morphology
Evaluated using Tygerberg Strict Criteria (%)
Time frame: At baseline and week 13
Serum Hormones (LH)
Change in luteinizing hormone (LH), shift analysis relative to reference ranges
Time frame: At Baseline and Week 13
Serum hormones (FSH)
Change in Follicle Stimulating Hormone (FSH), shift analysis relative to reference ranges
Time frame: At Baseline and Week 13
Serum Hormones (Testosterone)
Change in Testosterone, shift analysis relative to reference ranges
Time frame: At baseline and week 13
Plan to share: Undecided
This study is not yet recruiting, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Global Antibiotics Research and Development Partnership