NGU: Doxycycline (Plus or Minus Tinidazole) Versus Azithromycin (Plus or Minus Tinidazole)
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ClinicalTrials.gov Identifier: NCT00322465 |
Recruitment Status :
Completed
First Posted : May 8, 2006
Results First Posted : August 17, 2011
Last Update Posted : March 1, 2019
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Condition or disease | Intervention/treatment | Phase |
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Urethritis | Drug: Tinidazole Other: Placebo Drug: Doxycycline Drug: Azithromycin | Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 305 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Double (Participant, Investigator) |
Primary Purpose: | Treatment |
Official Title: | Phase II Randomized, Placebo-Controlled Double-Blind 4-Arm Trial for the Treatment of Non-Gonococcal Urethritis (NGU): Doxycycline (Plus or Minus Tinidazole) Versus Azithromycin (Plus or Minus Tinidazole) |
Study Start Date : | November 2006 |
Actual Primary Completion Date : | April 2009 |
Actual Study Completion Date : | April 2009 |

Arm | Intervention/treatment |
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Experimental: Doxycycline
Doxycycline 100 mg orally twice daily (2 pills/day = 200 mg/day) for 7 days plus placebo azithromycin orally single dose and placebo tinidazole.
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Other: Placebo
Placebo capsule will be filled with lactose only and be identical in appearance to the capsule of Azithromycin, Tinidazole, Doxycycline. Drug: Doxycycline 100 mg orally, twice daily for 7 days. |
Experimental: Doxycycline + Tinidazole
Doxycycline 100 mg orally twice daily for 7 days plus placebo azithromycin single dose plus tinidazole 2 gm orally single dose (4 tablets at 500 mg each).
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Drug: Tinidazole
2 gm single dose (4 tablets orally at 500 mg each). Other: Placebo Placebo capsule will be filled with lactose only and be identical in appearance to the capsule of Azithromycin, Tinidazole, Doxycycline. Drug: Doxycycline 100 mg orally, twice daily for 7 days. |
Experimental: Azithromycin
Azithromycin 1 gram (gm) orally single dose (2 tablets at 500 milligrams (mg) each) plus doxycycline placebo twice daily for 7 days plus tinidazole placebo single dose.
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Other: Placebo
Placebo capsule will be filled with lactose only and be identical in appearance to the capsule of Azithromycin, Tinidazole, Doxycycline. Drug: Azithromycin 1 gram (gm) (2 tablets orally at 500 milligrams (mg) each). |
Experimental: Azithromycin + Tinidazole
Azithromycin 1 gm orally single dose (2 tablets at 500 mg each) plus doxycycline placebo twice daily for 7 days plus tinidazole single dose (4 tablets at 500 mg each).
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Drug: Tinidazole
2 gm single dose (4 tablets orally at 500 mg each). Other: Placebo Placebo capsule will be filled with lactose only and be identical in appearance to the capsule of Azithromycin, Tinidazole, Doxycycline. Drug: Azithromycin 1 gram (gm) (2 tablets orally at 500 milligrams (mg) each). |
- Safety and Tolerability of Doxycycline/Tinidazole and Azithromycin/Tinidazole: Number of Participants Reporting Nausea [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]At all study visits, unsolicited adverse events were recorded. Nausea, Vomiting, Abdominal pain, and Diarrhea were recorded using National Cancer Institute Common Toxicity Criteria (Version 3.0).
- Safety and Tolerability of Doxycycline/Tinidazole and Azithromycin/Tinidazole: Number of Participants Reporting Vomiting [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]At all study visits, unsolicited adverse events were recorded. Nausea, Vomiting, Abdominal pain, and Diarrhea were recorded using National Cancer Institute Common Toxicity Criteria (Version 3.0).
- Safety and Tolerability of Doxycycline/Tinidazole and Azithromycin/Tinidazole: Number of Participants Reporting Stomach Upset [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]At all study visits, unsolicited adverse events were recorded.
- Safety and Tolerability of Doxycycline/Tinidazole and Azithromycin/Tinidazole: Number of Participants Reporting of Abdominal Pain [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]At all study visits, unsolicited adverse events were recorded. Nausea, Vomiting, Abdominal pain, and Diarrhea were recorded using National Cancer Institute Common Toxicity Criteria (Version 3.0).
- Safety and Tolerability of Doxycycline/Tinidazole and Azithromycin/Tinidazole: Number of Participants Reporting Diarrhea [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]At all study visits, unsolicited adverse events were recorded. Nausea, Vomiting, Abdominal pain, and Diarrhea were recorded using National Cancer Institute Common Toxicity Criteria (Version 3.0).
- Percentage of Participants Achieving Clinical Cure of Non-gonococcal Urethritis (NGU) With Doxycycline Versus Doxycycline With Tinidazole; and Azithromycin Versus Azithromycin With Tinidazole [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]
Clinical Cure of NGU: Did not meet criteria for clinical failure at last evaluable follow-up visit.
Clinical Failure at first follow-up: [Persistent symptoms AND >= 5 polymorphonuclear leukocytes (PMNs) per 3-5 oil immersion fields (regardless of urethral discharge)] OR Persistent urethral discharge on exam (regardless of symptoms or number of PMNs).
Clinical Failure at second follow-up: >= 5 PMNs per 3-5 oil immersion fields (regardless of symptoms or presence of urethral discharge) OR Persistent urethral discharge on exam (regardless of symptoms or number of PMNs)
- Percentage of Participants Achieving Clinical Cure of NGU With (Doxycycline Plus Doxycycline/Tinidazole) Versus (Azithromycin Plus Azithromycin/Tinidazole) [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]
Clinical Cure of NGU: Did not meet criteria for clinical failure at last evaluable follow-up visit.
Clinical Failure at first follow-up: [Persistent symptoms AND >= 5 PMNs per 3-5 oil immersion fields (regardless of urethral discharge)] OR Persistent urethral discharge on exam (regardless of symptoms or number of PMNs).
Clinical Failure at second follow-up: >= 5 PMNs per 3-5 oil immersion fields (regardless of symptoms or presence of urethral discharge) OR Persistent urethral discharge on exam (regardless of symptoms or number of PMNs)
- Percentage of Participants Achieving Microbiological Cure of Chlamydia Trachomatis With Doxycycline Versus Doxycycline With Tinidazole; and Azithromycin Versus Azithromycin With Tinidazole [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]Microbiological cure of Chlamydia trachomatis refers to the percentage of men with NGU who were negative for Chlamydia trachomatis at the last available result and had been positive for Chlamydia trachomatis at baseline.
- Percentage of Participants Achieving Microbiological Cure of Trichomonas Vaginalis With Doxycycline Versus Doxycycline With Tinidazole; and Azithromycin Versus Azithromycin With Tinidazole [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]Microbiological cure of Trichomonas vaginalis refers to the percentage of men with NGU who were negative for Trichomonas vaginalis (swab and urine specimens) at the last available result and had been positive for Trichomonas vaginalis at baseline (swab or urine specimen).
- Percentage of Participants Achieving Microbiological Cure of Mycoplasma Genitalium With Doxycycline Versus Doxycycline With Tinidazole; and Azithromycin Versus Azithromycin With Tinidazole [ Time Frame: First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]Microbiological Cure of Mycoplasma Genitalium refers to the percentage of men with NGU who were negative for Mycoplasma Genitalium at the last available result and had been positive for Mycoplasma Genitalium at baseline.
- Prevalence of Chlamydia Trachomatis in Men With Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment visit) ]Percentage of men with non-gonococcal urethritis that had a positive result for Chlamydia trachomatis at baseline (enrollment)
- Prevalence of Trichomonas Vaginalis (Swab or Urine Specimen) in Men With Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment visit) ]Percentage of men with non-gonococcal urethritis that had a positive result for Trichomonas vaginalis from a urethral swab or urine specimen at baseline (enrollment)
- Prevalence of Mycoplasma Genitalium in Men With Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment) ]Percentage of men with non-gonococcal urethritis that had a positive result for Mycoplasma genitalium at baseline (enrollment)
- Clinical, Behavioral, and Demographic Predictors of Chlamydia Trachomatis in Men With Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment visit) ]Clinical, behavioral, and demographic variables considered were discharge amount and appearance; condom use last sex; new recent partner; number of partners and new partners in last 30 days as well as last 3 months; number of times vaginal sex, oral sex, or anal sex in past 30 days; always/almost always used condom in last 3 months.
- Clinical, Behavioral, and Demographic Predictors of Trichomonas Vaginalis in Men With Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment visit) ]Trichomonas vaginalis was determined from urethral swab or urine specimen. Clinical, behavioral, and demographic predictors considered included discharge amount and appearance; condom use last sex; new recent partner; number of partners and new partners in last 30 days and last 3 months; number of times vaginal sex, oral sex, or anal sex in last 30 days; always/almost always used condom in last 3 months.
- Clinical, Behavioral, and Demographic Predictors of Mycoplasma Genitalium in Men With Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment visit) ]Logistic multiple regression with independent variable selection based on single variable models with p<0.10. Participants positive at enrollment for Mycoplasma genitalium from urine specimen. Potential variables: discharge amount and appearance; condom use last sex; new recent partner, number of partners and new partners in last 30 days and last 3 months; number of times vaginal sex, oral sex, or anal sex in last 30 days; always/almost always used condom last 3 months.
- Specimens for Future Studies to Determine the Role of Unique and Novel Pathogens in the Etiology of Non-gonococcal Urethritis [ Time Frame: Baseline (enrollment); First follow-up visit (Day 15-19), second follow-up visit (Day 35-45) ]Urethral swabs and urine specimens collected at each study visit for future studies to determine the role of unique and novel pathogens in the etiology of non-gonococcal urethritis

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Ages Eligible for Study: | 16 Years to 45 Years (Child, Adult) |
Sexes Eligible for Study: | Male |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Male, 16 to 45 years old.
- Symptoms of non-gonococcal urethritis (NGU), including urethral discharge and/or dysuria for less than or equal to 14 days, or urethral discharge on exam.
- Urethral smear with greater than or equal to 5 polymorphonuclear leukocytes (PMNs) per 3-5 oil immersion fields.
- Willing to abstain from sexual intercourse or use condoms during the study.
- Willingness to provide written consent.
Exclusion Criteria:
- Presence of gonorrhea at baseline visit.
- History of recurrent non-gonococcal urethritis (NGU) (3 or more episodes in the prior year) or history of recent NGU (within past 30 days).
- Signs or symptoms of epididymitis or prostatitis.
- Known allergy to or intolerance of tinidazole, tetracyclines, macrolides or metronidazole.
- History of photosensitivity related to doxycycline use.
- Received systemic antibiotics within 30 days of study enrollment.
- Unwillingness to abstain from alcohol for 24 hours after enrollment.
- Serious underlying infection, including known HIV or other primary or secondary immunosuppression.
- Concomitant infection, which requires antimicrobial therapy.
- History of mental illness, which would preclude responsible participation in the study.
- Current drug abuse that might affect ability to follow the protocol.
- Previously enrolled in this study.
- Men who have sex with men, due to different microbiology of NGU.
- Voided within the previous hour.
- Ingested alcohol within the past 8 hours.
- Subject requires concurrent lithium, anticoagulation therapy, or antabuse.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00322465
United States, Alabama | |
University of Alabama Hospital - Infectious Diseases | |
Birmingham, Alabama, United States, 35249-0001 | |
United States, Louisiana | |
Delgado Personal Health Center | |
New Orleans, Louisiana, United States, 70112-3503 | |
United States, Maryland | |
Johns Hopkins Hospital - Emergency Medicine | |
Baltimore, Maryland, United States, 21287-0005 | |
United States, North Carolina | |
University of North Carolina School of Medicine - Center for Infectious Diseases | |
Chapel Hill, North Carolina, United States, 27599-7030 |
Responsible Party: | National Institute of Allergy and Infectious Diseases (NIAID) |
ClinicalTrials.gov Identifier: | NCT00322465 |
Other Study ID Numbers: |
05-0120 |
First Posted: | May 8, 2006 Key Record Dates |
Results First Posted: | August 17, 2011 |
Last Update Posted: | March 1, 2019 |
Last Verified: | May 2011 |
non-gonococcal urethritis, doxycycline, azithromycin, sexually transmitted, tinidazole |
Urethritis Urethral Diseases Urologic Diseases Azithromycin Doxycycline Tinidazole Anti-Bacterial Agents |
Anti-Infective Agents Antimalarials Antiprotozoal Agents Antiparasitic Agents Alkylating Agents Molecular Mechanisms of Pharmacological Action Antitrichomonal Agents |