Skip to content
Clinical Trials – home

Rare diseases

Investigational molecules

Locations

Our offerNewsroom

Not yet recruiting

Study of Topical Chloramphenicol vs Topical Ciprofloxacin for Treating Otorrhea in Adults with Chronic Suppurative Otitis Media

Verified siteRegistered drugNo placebo
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

Chronic suppurative otitis media is a long‑lasting infection of the middle ear that often causes continuous ear discharge (otorrhea) and can affect hearing. The study compares two types of ear drops: one containing chloramphenicol and the other containing ciprofloxacin. Both medications are applied directly into the ear to treat the infection.

The purpose of the study is to find out whether the chloramphenicol drops work at least as well as the ciprofloxacin drops in stopping ear discharge in adults with this condition. Participants will use the assigned ear drops for about two weeks. Doctors will examine the ear using a light‑based tool (otoscopy) and take pictures to see if the discharge has cleared. Hearing will be checked with a simple beep test (pure‑tone audiometry) at the start and after the treatment period. Throughout the study, participants will note any irritation, pain, or other side effects and answer questions about how they feel and how satisfied they are with the treatment.

The research process

The trial runs in 3 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Baseline visit

    On day 1 the patient attends the initial clinic visit.

    The patient undergoes an ear examination (otoscopy) and a hearing test (pure‑tone audiometry) to record baseline measurements.

    The patient completes a quality‑of‑life questionnaire specific to chronic ear infection.

    The patient receives the assigned medication: either chloramphenicol ear drops (2 mg per dose) or ciprofloxacin ear drops (1.2 mg per dose).

    Written instructions are provided on how to apply the ear drops and how to complete the treatment diary.

  2. Step 2

    Medication administration

    From day 1 through day 14 the patient applies the assigned ear drops according to the written instructions (dose and frequency as specified by the study protocol).

    The patient records each use in the treatment diary, noting date, time, and any discomfort.

  3. Step 3

    End‑of‑treatment visit

    On day 14 the patient returns to the clinic for the final assessment.

    The patient undergoes a repeat ear examination and hearing test to evaluate resolution of ear discharge and changes in hearing thresholds.

    The patient completes the same quality‑of‑life questionnaire to compare with the baseline response.

    The patient returns any unused medication and the completed treatment diary for adherence assessment.

Who can join the trial?

4 criteria

  • Age 18 years or older – you must be an adult (at least 18 years old) to join the study.
  • Confirmed diagnosis of Chronic Suppurative Otitis Media (CSOM) – you must have a long‑lasting ear infection that causes persistent drainage from the ear.
  • Ability to follow the study instructions and attend all visits – you need to be able to do what the study asks (like using ear drops) and come to each scheduled appointment.
  • Signed written informed consent – you must read and sign a form showing you understand the study and agree to take part.

Who cannot join the trial?

11 criteria

  • Having taken any antibiotic (a medicine that kills bacteria) by ear drops or by mouth/injection in the month before the study.
  • Participating in another clinical trial within the 30 days before joining this study.
  • Having a health problem, life situation, or taking other medicines that the doctor thinks would make it hard to follow the study plan or could be unsafe.
  • Being allergic or having a strong reaction to chloramphenicol, ciprofloxacin, or any of the other ingredients listed (Povidone K30, Boric Acid, Sodium Borate, Sodium Chloride, parabens).
  • Having moderate or severe liver problems (called hepatic impairment), which could increase the risk of liver damage (hepatotoxicity).
  • Having very severe kidney disease (renal failure) with an eGFR (a test that measures kidney function) less than 20 mL/min/1.73 m².
  • Being a woman who could become pregnant, having a negative pregnancy test now, but not agreeing to use reliable birth control during the study.
  • Having a fungal infection of the ear canal (called otomycosis).
  • Having a blood‑forming (hematological) or bone‑marrow disorder, either in the past or currently active.
  • Using, or planning to use, any other ear drops (including other antibiotics, antifungal ear drops, or steroid ear drops) in the last 7 days or during the study.
  • Needing to take oral (systemic) antibiotics, antifungal medicines, or medicines that suppress the immune system (including oral steroids) during the study, because these could interfere with the study drug.
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not yet recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

  • Ciprofloxacin

    ear drops are a medication applied directly into the ear. In this study they are used as the standard treatment (comparator) to see how well they stop ear discharge (otorrhea) in adults with chronic ear infection. The drops contain an antibiotic that works by killing the bacteria that cause the infection, helping the ear heal.

  • Chloramphenicol

    ear drops are another antibiotic that is placed in the ear. In the trial they are the test treatment being compared to ciprofloxacin. The purpose is to find out if chloramphenicol works at least as well as ciprofloxacin in clearing the ear discharge in adults with chronic suppurative otitis media. It works by stopping bacterial growth, which can reduce infection and promote healing.

What is already known about the treatment

  • Ciprofloxacin

    This medication is supplied as ear drops (a clear solution) that are placed directly into the ear canal. It is an approved, widely studied antibiotic that is commonly used to treat bacterial ear infections, including chronic suppurative otitis media. It works by blocking an enzyme called DNA gyrase, which stops bacteria from copying their DNA and growing. Ciprofloxacin belongs to the fluoroquinolone class of antibiotics.

  • Chloramphenicol

    This medication is provided as a topical ear preparation that is applied directly to the ear. It is an older, still approved antibiotic that is used for bacterial ear infections such as chronic suppurative otitis media, though resistance can be a concern. It stops bacteria from making proteins by attaching to their ribosomes, which halts bacterial growth. Chloramphenicol is classified as a broad‑spectrum amphenicol antibiotic.

Investigated diseases

Chronic suppurative otitis media - It is a long‑lasting infection of the middle ear that causes persistent drainage through the ear canal. The condition usually follows repeated ear infections and leads to a perforated eardrum that does not heal. Over time, the ear may produce continuous or intermittent pus‑filled fluid, and the lining of the middle ear can become thickened and scarred.
Trial detailsLast updated 7 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2026-525540-15-00Protocol codeOMCOSEstimated enrolment88 patientsSponsorInstitut De Recerca Biomedica De Lleida Fundacio Dr. Pifarre

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.