Clinical trial Recruiting at 19 sites Phase 3 Interventional Ages 18 and up

Clarithromycin to help prevent secondary infections in adults with pneumonia and sepsis

Official title: CLARITHROMYCIN TO PREVENT SECONDARY INFECTIONS IN PATIENTS WITH SEPSIS FOLLOWING LOWER RESPIRATORY TRACT INFECTIONS: THE CLASSIFY TRIAL

Run by Hellenic Institute for the Study of Sepsis · NCT07834346 · Data updated 2026-11-12

This study tests whether adding clarithromycin to standard antibiotics can reduce new infections and secondary sepsis in adults hospitalized with community-acquired pneumonia and sepsis.

More Sepsis trials

Quick facts

PhasePhase 3
Study typeInterventional
Ages18 Years and up
SexAll
Enrollment252 (estimated)
SponsorHellenic Institute for the Study of Sepsis
Academic / other
Drugs / interventionsprednisone, immunotherapy
Locations19 sites (Pátrai, Achaea and 18 other locations)
StatusRecruiting
StartedSeptember 16, 2026
Main results expectedOctober 2029
Study endsDecember 2029
Registry record updatedNovember 3, 2026
Trial IDNCT07834346 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Adults 18 years and older with CAP and sepsis, including sepsis-induced immunoparalysis, who can provide informed consent or have a legally authorized representative consent on their behalf.

Probably not a fit

Patients who do not develop additional infections or sepsis within 28 days or who do not respond to clarithromycin may derive no benefit or could experience no improvement.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This Phase 3 trial compares clarithromycin plus standard-of-care antibiotics versus placebo plus standard-of-care in adults with CAP and sepsis, including those with sepsis-induced immunoparalysis. The primary outcome is the incidence of new infections or worsening of CAP within 28 days. Secondary outcomes include mortality, sepsis response, timing of antimicrobial escalation, hospital readmission, quality of life, cost-effectiveness, and immune biomarkers. The trial seeks to determine if clarithromycin can modulate the immune response and reduce secondary infections in this high-risk population.

Why it matters

Potential benefit: If successful, clarithromycin could reduce secondary infections and sepsis-related complications, potentially shortening hospital stays and improving survival.

How similar studies have gone: Previous research in similar approaches has shown signals of benefit in immune-modulating strategies, but results with clarithromycin for preventing secondary infections in sepsis are still being investigated.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age equal to or above 18 years
* Patients of either gender
* Written informed consent provided by the patient. For patients without decision-making capacity, informed consent must be obtained from a legally designated representative following the national legislation.
* Negative (blood or urinary) pregnancy test for female patients of reproductive age
* For female patients of reproductive age, willingness to use highly effective contraception during and seven days after the administration of the IMP.
* Presence of Community-acquired pneumonia (CAP)
* Presence of sepsis as defined by the Sepsis-3 classification criteria (at least 2 points increase of the total SOFA-1 score from the baseline score of the specific patient). The SOFA score which will be used for the definition of sepsis has recently been renamed SOFA-1.
* Absolute lymphocyte count (ALC) less than 1000/mm³.

Exclusion Criteria:

* Age below 18 years
* Denial of written informed consent
* Pregnancy (confirmed by blood or urinary pregnancy test) or lactation for female patients
* Unwillingness to receive contraception during and seven days after the administration of the IMPstudy drug (for Female patients)
* Known HIV infection with known CD4 cell count \<200/mm³
* Solid organ or bone marrow transplantation
* Corticosteroid oral or intravenous intake greater than 0.4mg/kg of equivalent prednisone daily over the last 15 days or other immunosuppressive therapy. However, corticosteroids received as adjunctive treatment for the current septic/infectious episode are allowed
* Intake of a biological agent in the last month
* Known active neoplasms or other conditions unrelated to sepsis that compromise short-term survival less than 6 months
* Neutropenia \< 500/mm³
* Intake of any macrolide for the current episode of CAP under study
* QTc interval at rest in the ECG ≥500 msec or history of known long QT syndrome
* Medical history of allergy to macrolides
* Concomitant use of medicinal products contraindicated with clarithromycin, including CYP3A substrates associated with QT prolongation (e.g., astemizole, cisapride, domperidone, pimozide, terfenadine, ivabradine), ergot alkaloids (e.g., ergotamine, dihydroergotamine), oral midazolam, HMG-CoA reductase inhibitors primarily metabolised by CYP3A4 (e.g., lovastatin, simvastatin), colchicine, ticagrelor, and ranolazine. This criterion applies to all medicinal products within these classes, not only the specific examples listed, in accordance with the SmPC for clarithromycin. Patients may be enrolled provided that such medications are discontinued prior to or at the time of trial participation. Given their short half-life, no wash-out period is required
* Medical history of torsades de pointes arrhythmia
* Severe hypokalemia or hypomagnesemia; patients may be enrolled once these electrolyte abnormalities are corrected.
* Any contradictions for macrolide uptake
* Previous participation in the CLASSIFY study
* Participation in any other interventional trial within the last 30 days
* Severe hepatic failure in combination with renal impairment

Where it's running

  • General University Hospital of Patras, Department of Internal Medicine
    Pátrai, Achaea, Greece
    Recruiting
  • Evaggelismos Hospital, 1st Department of Internal Medicine
    Athens, Attica, Greece
    Recruiting
  • General Hospital of Athens Korgialenio Benakio H.R.C, Intensive Care Unit
    Athens, Attica, Greece
    Recruiting
  • General Hospital of Athens Korgialenio Benakio H.R.C., 1st Department of Internal Medicine
    Athens, Attica, Greece
    Recruiting
  • General Hospital of Athens G.Gennimatas, 1st Department of Internal Medicine
    Athens, Attica, Greece
    Recruiting
  • Thoracic General Hospital of Athens I Sotiria, 3rd University Department of Internal Medicine
    Athens, Attica, Greece
    Recruiting
Show 13 more locations
  • Thoracic General Hospital of Athens I Sotiria, 6th Department of Pulmonary Medicine
    Athens, Attica, Greece
    Recruiting
  • General Hospital of Athens Alexandra, Ηigh Dependency Unit of Department of Clinical Therapeutics
    Athens, Attica, Greece
    Recruiting
  • University General Hospital Attikon-General Hospital of West Attica H Agia Varvara, 2nd Department of Propaedeutic Medicine
    Athens, Attica, Greece
    Recruiting
  • University General Hospital Attikon-General Hospital of West Attica H Agia Varvara, 4th Department of Internal Medicine
    Athens, Attica, Greece
    Recruiting
  • General Oncological Hospital of Kifisia Agioi Anargyroi, Intensive Care Unit
    Athens, Attica, Greece
    Recruiting
  • University General Hospital of Ioannina, 1st Department of Internal Medicine
    Ioannina, Ioannina, Greece
    Recruiting
  • University General Hospital of Thessaloniki Ahepa, Intensive Care Unit
    Thessaloniki, Thessaloniki, Greece
    Recruiting
  • Ippokratio General Hospital of Thessaloniki, 2nd Propaedeutic Department of Internal Medicine
    Thessaloniki, Thessaloniki, Greece
    Recruiting
  • General Hospital of Thessaloniki Papageorgiou, Department of Internal Medicine
    Thessaloniki, Thessaloniki, Greece
    Recruiting
  • Geniko Nosokomeio Thessalonikis George Papanikolaou, Intensive Care Unit
    Thessaloniki, Thessaloniki, Greece
    Recruiting
  • University General Hospital of Alexandroupolis, 2nd Department of Internal Medicine
    Alexandroupoli, Thrace, Greece
    Recruiting
  • General Hospital of Eleusina Thriasio, 1st Department of Internal Medicine
    Elefsina, West Attica, Greece
    Recruiting
  • General Hospital of Eleusina Thriasio, 2nd Department of Internal Medicine
    Elefsina, West Attica, Greece
    Recruiting

Study contacts

Similar studies

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How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.