Ongoing study
Official Study Title
CLARITHROMYCIN TO PREVENT SECONDARY INFECTIONS IN PATIENTS WITH SEPSIS FOLLOWING LOWER RESPIRATORY TRACT INFECTIONS
Brief Description
The goal of this clinical trial is to assess whether clarithromycin, given as an adjunct to standard-of-care antibiotic therapy, can reduce the risk of new infections and secondary sepsis in adult patients hospitalized with community-acquired pneumonia (CAP), sepsis, and sepsis-induced immunoparalysis (SII). The primary objective is to evaluate the effect of clarithromycin on the incidence of new infection, including worsening or recurrence of the initial CAP episode, new infections at other sites, and secondary sepsis during the 28-day follow-up period. Secondary objectives are to investigate the impact of clarithromycin on mortality, sepsis response, type of secondary infection, time to antimicrobial escalation, hospital readmission, quality of life, cost-effectiveness, and biomarkers of sepsis-induced immunoparalysis.
Details
Status: Recruiting
Study Type: Interventional (Clinical Trial)
Study phase: III
Study sites: 19 sites in Greece
Target of enrolment: 252 participants
ClinicalTrials.gov Identifier: NCT07834346
CTIS number: 2025-525058-20-00
Study Start: September 2026
Condition/Disease studied: community-acquired pneumonia (CAP), sepsis, and sepsis-induced immunoparalysis (SII)
Keywords: clarithromycin
Connect to the CLASSIFY trial portal
CLASSIFY Research Network
CLASSIFY RESEARCH NETWORK
Welcoming Professor Eleni Argyriadou to the CLASSIFY Research Network
📅 14 October 2026 · Site Initiation Visit completed
AHEPA University General Hospital
With the Intensive Care Unit, AHEPA contributes both its clinical expertise and recruitment capacity to CLASSIFY.
Thessaloniki, Greece
On 14 October 2026, the Intensive Care Unit (ICU) of AHEPA University General Hospital in Thessaloniki joined the CLASSIFY research network following its site activation.
The participation of AHEPA brings together two areas closely connected to the scientific objectives of CLASSIFY:Â Intensive Care Medicine and Anesthesiology. With extensive clinical experience in managing critically ill patients and an active presence in clinical research, the Unit provides an important setting for the identification and study of patients with sepsis.
Intensive Care expertise supporting CLASSIFY
The study at AHEPA is led by Professor Eleni Argyriadou, Director of the Department of Anesthesiology and Intensive Care at Aristotle University of Thessaloniki, whose clinical and academic work spans Anesthesiology, Intensive Care Medicine, and the management of critically ill patients.
Her research activity includes studies investigating clinical outcomes in critically ill patients, in-hospital cardiac arrest, and factors influencing patient survival, combining clinical practice with an active academic and research background.
Together with her research team, she brings this experience directly into CLASSIFY, supporting the study’s effort to better understand and characterize sepsis in real-world intensive care practice.
From site activation to patient recruitment
With the Intensive Care Unit activated on 14 October 2026, AHEPA contributes both its clinical expertise and recruitment capacity to CLASSIFY.
Its participation reflects what CLASSIFY is built around:Â bringing together experienced clinical teams from different settings to address the complexity of sepsis through collaborative research.
CLASSIFY. Bringing expertise together to advance sepsis research.
CLASSIFY RESEARCH NETWORK
Welcoming Professor Periklis Panagopoulos to the CLASSIFY Research Network
📅 9 October 2026 · Site Initiation Visit completed
University General Hospital of Alexandroupolis
The 2nd Department of Internal Medicine strengthens the clinical expertise and recruitment potential of the CLASSIFY network.
Alexandroupolis, Greece
On 9 October 2026, the 2nd Department of Internal Medicine of the University General Hospital of Alexandroupolis joined the CLASSIFY research network following its site activation.
The participation of Alexandroupolis brings together two areas closely connected to the scientific objectives of CLASSIFY: Internal Medicine and Infectious Diseases. With extensive clinical experience in managing patients with severe infections and an active presence in clinical research, the Department provides an important setting for the identification and study of patients with sepsis.
Infectious Diseases expertise supporting CLASSIFY
The study at Alexandroupolis is led by Professor Periklis Panagopoulos, MD, PhD, Internist and Infectious Diseases Specialist, whose clinical and academic work focuses on infectious diseases and the management of complex infections.
With active involvement in clinical research conducted through the Hellenic Institute for the Study of Sepsis (HISS), Professor Panagopoulos has contributed to studies investigating severe infections and therapeutic approaches. His research involvement includes the REACT clinical trial, a multicenter study investigating biomarker-guided early clarithromycin treatment to prevent the progression of community-acquired pneumonia to sepsis.
Together with his research team, he brings this experience directly into CLASSIFY, supporting the study’s effort to better understand and characterize sepsis in real-world clinical practice.
From site activation to patient recruitment
With the 2nd Department of Internal Medicine activated on 9 October 2026 and preparing for patient screening, the University General Hospital of Alexandroupolis strengthens the clinical expertise and recruitment potential of the CLASSIFY network.
Its participation reflects what CLASSIFY is built around: bringing together experienced clinical teams from different settings to address the complexity of sepsis through collaborative research.
CLASSIFY. Bringing expertise together to advance sepsis research.
CLASSIFY RESEARCH NETWORK
Welcoming Professor Charalampos Milionis to the CLASSIFY Research Network
📅 8 October 2026 · Site Initiation Visit completed
University Hospital of Ioannina
The 1st Department of Internal Medicine contributes both its clinical expertise and recruitment capacity to CLASSIFY.
Ioannina, Greece
On 8 October 2026, the 1st Department of Internal Medicine of the University Hospital of Ioannina joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
The participation of the University Hospital of Ioannina brings together two areas closely connected to the scientific objectives of CLASSIFY:Â Internal Medicine and Clinical Research in Severe Infections. With extensive clinical experience and an active presence in research, the Department provides an important setting for the identification and study of patients with sepsis.
Internal Medicine expertise supporting CLASSIFY
The study at the University Hospital of Ioannina is led by Professor Charalampos Milionis, MD, PhD, Director of the 1st Department of Internal Medicine, whose clinical and academic work spans Internal Medicine and clinical research.
With more than 400 peer-reviewed scientific publications, he brings extensive academic and research experience to the CLASSIFY network.
His involvement in multicenter clinical studies conducted through the Hellenic Institute for the Study of Sepsis (HISS) includes the ACCESS and REACT clinical trials, investigating therapeutic approaches in patients with community-acquired pneumonia and strategies to prevent progression to sepsis.
Together with his research team, he brings this experience directly into CLASSIFY, supporting the study’s effort to better understand and characterize sepsis in real-world clinical practice.
From site activation to patient recruitment
With the 1st Department of Internal Medicine activated on 8 October 2026 and ready for patient screening, the University Hospital of Ioannina contributes both its clinical expertise and recruitment capacity to CLASSIFY.
Its participation reflects what CLASSIFY is built around:Â bringing together experienced clinical teams from different settings to address the complexity of sepsis through collaborative research.
CLASSIFY. Bringing expertise together to advance sepsis research.
CLASSIFY RESEARCH NETWORK
Welcoming Dr Ioannis A. Dimitroulis to the CLASSIFY Research Network
📅 30 September 2026 · Site Initiation Visit completed
Evangelismos General Hospital
The 6th Department of Pulmonary Medicine has added a specialized respiratory medicine setting to the CLASSIFY research network.
Athens, Greece
On 30 September 2026, the 6th Department of Pulmonary Medicine of Sotiria General Hospital joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
Respiratory infections represent an important clinical challenge, particularly when pneumonia progresses to severe infection and sepsis. Within this context, the Department brings a pulmonary medicine perspective to CLASSIFY, connecting the management of respiratory disease with the study of systemic responses to infection.
From respiratory infection to systemic illness
The CLASSIFY study at Sotiria General Hospital is led by Dr Ioannis A. Dimitroulis, MD, PhD, Director of the 6th Department of Pulmonary Medicine, together with his clinical and research team.
His clinical and scientific experience spans several areas of Respiratory Medicine, including interventional bronchoscopy, interstitial lung diseases, respiratory physiology and the management of complex pulmonary conditions.
Dr Dimitroulis has also contributed to clinical research in sepsis, including participation in the REACT clinical study. This research experience, combined with his expertise in Pulmonary Medicine, provides a strong clinical and scientific foundation for his contribution to CLASSIFY and its focus on sepsis.
Bringing a pulmonary perspective to sepsis research
Since its activation on 30 September 2026, the 6th Department of Pulmonary Medicine has added a specialized respiratory medicine setting to the CLASSIFY research network.
The participation of Dr Dimitroulis and his team strengthens the multidisciplinary character of CLASSIFY, connecting pulmonary medicine with the broader scientific effort to understand why some patients with respiratory infections progress to sepsis while others recover.
CLASSIFY. Understanding sepsis, from the lungs to the whole patient.
CLASSIFY RESEARCH NETWORK
Welcoming Professor Eleni Boutati to the CLASSIFY Research Network
📅 30 September 2026 · Site Initiation Visit completed
ATTIKON University General Hospital
The 2nd Propaedeutic Department of Internal Medicine provides a strong clinical and scientific foundation for CLASSIFY.
Athens, Greece
On 30 September 2026, the 2nd Propaedeutic Department of Internal Medicine & Research Institute of “ATTIKON” University General Hospital joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
As a university-based clinical department, the 2nd Propaedeutic Department of Internal Medicine & Research Institute combines patient care, medical education and clinical research across a broad range of medical specialties. This multidisciplinary environment provides an important setting for CLASSIFY, particularly in understanding how severe infections and sepsis may affect patients with different underlying medical conditions.
Connecting Internal Medicine, Infectious Diseases and clinical research
The CLASSIFY study at ATTIKON University General Hospital is led by Professor Eleni Boutati, MD, PhD, Professor of Internal Medicine and Diabetes Mellitus at the Medical School of National and Kapodistrian University of Athens and Infectious Diseases Specialist.
Her clinical and scientific experience spans Internal Medicine, Infectious Diseases, Diabetes Mellitus and metabolic disorders. Her professional background also includes specialized training in Infectious Diseases at the MD Anderson Cancer Center in Houston, Texas, and participation in clinical research, including the REACT clinical study.
This research experience, combined with her expertise in Internal Medicine and Infectious Diseases, provides a strong clinical and scientific foundation for her contribution to CLASSIFY, particularly in understanding the interaction between severe infections, underlying medical conditions and the patient’s systemic response.
Exploring sepsis across complex patient populations
Since its activation on 30 September 2026, the 2nd Propaedeutic Department of Internal Medicine has added a clinical and academic setting to CLASSIFY that brings together different medical specialties and experience in managing patients with complex health conditions.
The participation of Professor Boutati and her research team contributes to the multidisciplinary character of CLASSIFY, supporting the effort to better understand how individual patient characteristics and underlying diseases may influence the progression of severe infections and sepsis.
CLASSIFY. Understanding sepsis through the complexity of every patient.
CLASSIFY RESEARCH NETWORK
Welcoming Dr Vasiliki Tzavara to the CLASSIFY Research Network
📅 29 September 2026 · Site Initiation Visit completed
Hellenic Red Cross General Hospital
The 1st Department of Internal Medicine has brought to CLASSIFY a clinical team with previous research experience and direct involvement in the management of patients with complex medical conditions.
Athens, Greece
On 29 September 2026, the 1st Department of Internal Medicine of Korgialenio–Benakio Hellenic Red Cross General Hospital joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
The Department provides care to patients with a broad range of medical conditions, including complex clinical cases and severe infections. This clinical environment offers an important perspective for CLASSIFY, where understanding the progression of infection and the systemic response of the patient is central to the study’s scientific objectives.
Building on clinical experience and sepsis research
The CLASSIFY study at Korgialenio–Benakio Hellenic Red Cross General Hospital is led by Dr Vasiliki Tzavara, together with the clinical and research team of the 1st Department of Internal Medicine.
Her clinical experience in Internal Medicine, combined with her previous participation in the REACT clinical study, brings relevant experience in clinical research to CLASSIFY.
This involvement reflects a continuing contribution to research focused on severe infections and sepsis, connecting experience from previous clinical studies with the scientific objectives of CLASSIFY.
Together with her research team, Dr Tzavara contributes to the study’s efforts to better understand the different clinical presentations and progression of sepsis in patients with complex medical conditions.
Continuing the research journey through CLASSIFY
Since its activation on 29 September 2026, the 1st Department of Internal Medicine has brought to CLASSIFY a clinical team with previous research experience and direct involvement in the management of patients with complex medical conditions.
The participation of Dr Tzavara and her team strengthens the collaboration between clinical practice and research, supporting the broader effort to improve our understanding of sepsis.
CLASSIFY. Building on experience, advancing sepsis research.
CLASSIFY RESEARCH NETWORK
Welcoming Dr Theano Kontopoulou to the CLASSIFY Research Network
📅 24 September 2026 · Site Initiation Visit completed
Evangelismos General Hospital
The 1st Department of Internal Medicine has brought to CLASSIFY the perspective of a busy tertiary-care Internal Medicine setting.
Athens, Greece
On 24 September 2026, the 1st Department of Internal Medicine of Evangelismos General Hospital joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
Within one of the country’s major tertiary hospitals, the Department manages a broad spectrum of complex medical conditions, including patients with serious infections. This breadth of Internal Medicine provides CLASSIFY with an important clinical setting in which sepsis may emerge across different diseases, patient profiles and clinical presentations.
From severe infection to understanding the underlying response
CLASSIFY at Evangelismos General Hospital is led by Theano Kontopoulou, MD, PhD, Internist and Coordinating Director of the 1st Department of Internal Medicine.
Her recent scientific activity includes research in serious infections and pneumonia, including authorship of a 2026 EBioMedicine publication investigating molecular pathways associated with the benefit of clarithromycin in community-acquired pneumonia, based on data from the randomized ACCESS trial.
This work reflects an approach that goes beyond the clinical presentation of infection to explore the biological mechanisms underlying treatment response – a perspective that closely complements CLASSIFY and its effort to better understand the heterogeneity of patients with sepsis.
Bringing the breadth of Internal Medicine to CLASSIFY
Since its activation on 24 September 2026, the 1st Department of Internal Medicine has brought to CLASSIFY the perspective of a busy tertiary-care Internal Medicine setting, where severe infections are encountered within a diverse and often complex patient population.
Through Dr Kontopoulou and her team, this broad clinical experience is combined with research focused on understanding why patients with serious infections may respond differently to treatment.
CLASSIFY. From clinical complexity to a deeper understanding of sepsis.
CLASSIFY RESEARCH NETWORK
Welcoming Professor Karolina-Anthoula Akinosoglou to the CLASSIFY Research Network
📅 21 September 2026 · Site Initiation Visit completed
University General Hospital of Patras
The Department of Internal Medicine has brought to CLASSIFY a clinical and academic environment with dedicated expertise in Infectious Diseases.
Patra, Greece
On 21 September 2026, the Department of Internal Medicine of the University General Hospital of Patras joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
With a dedicated Infectious Diseases Unit, the Department combines Internal Medicine with specialized expertise in the diagnosis and management of infections. Its clinical, educational and research activity creates an environment closely connected to some of the most important challenges surrounding sepsis — from recognizing severe infection to selecting appropriate antimicrobial treatment.
Where infection, sepsis and antimicrobial resistance intersect
CLASSIFY at the University General Hospital of Patras is led by Professor Karolina-Anthoula Akinosoglou, MD, PhD, Professor of Internal Medicine at the University of Patras.
Her scientific interests span Internal Medicine, Infectious Diseases, sepsis syndrome and antimicrobial resistance, bringing together areas that are increasingly interconnected in the management of patients with severe infections.
This perspective is particularly relevant to CLASSIFY. Sepsis does not exist in isolation: the characteristics of the infection, the patient’s response and the challenges posed by antimicrobial resistance can all shape the clinical course and the decisions made at the bedside.
Adding another perspective to CLASSIFY
Since its activation on 21 September 2026, the Department of Internal Medicine has brought to CLASSIFY a clinical and academic environment with dedicated expertise in Infectious Diseases and a strong scientific interest in sepsis and antimicrobial resistance.
Through the participation of Professor Akinosoglou and her team, CLASSIFY continues to bring together complementary areas of expertise to build a broader picture of sepsis across different clinical settings.
CLASSIFY. Different perspectives, one challenge: understanding sepsis.
CLASSIFY RESEARCH NETWORK
Welcoming Professor Georgios Dimopoulos to the CLASSIFY Research Network
📅 21 September 2026 · Site Initiation Visit completed
Alexandra General Hospital
The High Dependency Unit has brought CLASSIFY into a clinical setting with direct experience in managing some of the most severely ill patients within the study population.
Athens, Greece
On 17 September 2026, the High Dependency Unit (HDU) of the Department of Clinical Therapeutics at Alexandra General Hospital joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
For CLASSIFY, the participation of the HDU brings the study directly into a clinical environment where the complexity of severe infection is encountered every day. The Unit provides specialized care for critically ill patients, including patients with septic shock, supported by mechanical respiratory support and advanced hemodynamic monitoring.
This direct exposure to severe and rapidly evolving illness makes the HDU particularly relevant to the study’s effort to better characterize patients with sepsis.
Sepsis expertise with a precision-medicine perspective
The study is led by Professor Georgios Dimopoulos, MD, PhD, Professor of Pulmonary and Critical Care Medicine at the National and Kapodistrian University of Athens and Consultant in Critical Care at the Department of Clinical Therapeutics of Alexandra General Hospital.
His clinical and scientific work spans critical care, sepsis, severe and respiratory infections, and infections in critically ill patients. With more than 300 scientific publications and reviews, Professor Dimopoulos brings extensive research experience to CLASSIFY.
His involvement in the ImmunoSep randomized clinical trial on precision immunotherapy in sepsis adds a particularly relevant dimension: experience in research exploring how the biological complexity of sepsis can inform more targeted therapeutic approaches.
Bringing CLASSIFY closer to the complexity of severe sepsis
Since its activation on 17 September 2026, the High Dependency Unit has brought CLASSIFY into a clinical setting with direct experience in managing some of the most severely ill patients within the study population.
The participation of Professor Dimopoulos and his team strengthens CLASSIFY not only through recruitment, but through critical care and sepsis expertise closely aligned with the scientific questions at the heart of the study.
CLASSIFY. Understanding sepsis where every clinical decision matters.
CLASSIFY RESEARCH NETWORK
Welcoming Professor Antonios Papadopoulos to the CLASSIFY Research Network
📅 14 September 2026 · Site Initiation Visit completed
ATTIKON University General Hospital
The 4th Department of Internal Medicine contributes both its clinical expertise and recruitment capacity to CLASSIFY.
Athens, Greece
On 14 September 2026, the 4th Department of Internal Medicine of ATTIKON University General Hospital joined the CLASSIFY research network following the successful completion of its Site Initiation Visit (SIV).
The participation of ATTIKON brings together two areas closely connected to the scientific objectives of CLASSIFY:Â Internal Medicine and Infectious Diseases. With extensive clinical experience in the management of patients with severe infections and an active presence in clinical research, the Department provides an important setting for the identification and study of patients with sepsis.
Infectious Diseases expertise supporting CLASSIFY
The study at ATTIKON is led by Professor Antonios Papadopoulos, MD, PhD, Internist and Infectious Diseases Specialist, whose clinical and academic work has been closely linked to infectious diseases.
With more than 140 peer-reviewed publications, Professor Papadopoulos’ research spans infectious diseases, public health and emerging infections, combining clinical practice with a strong academic and research background.
Together with his research team, he brings this experience directly into CLASSIFY, supporting the study’s effort to better understand and characterize sepsis in real-world clinical practice.
From site activation to patient recruitment
With the 4th Department of Internal Medicine activated on 14 September 2026 and ready for patient screening, ATTIKON contributes both its clinical expertise and recruitment capacity to CLASSIFY.
Its participation reflects what CLASSIFY is built around:Â bringing together experienced clinical teams from different settings to address the complexity of sepsis through collaborative research.
CLASSIFY. Bringing expertise together to advance sepsis research.
CLASSIFY RESEARCH NETWORK
Welcoming Dr Athina Lavrentieva to the CLASSIFY Research Network
📅 10 September 2026 · Site Initiation Visit completed
G. Papanikolaou General Hospital
The 1st Intensive Care Unit brings critical care expertise to the CLASSIFY study, marking the activation of the network’s first ICU.
Thessaloniki, Greece
On 10 September 2026, the 1st Intensive Care Unit (ICU) of G. Papanikolaou General Hospital officially joined the CLASSIFY research network, following the successful completion of its Site Initiation Visit (SIV).
The activation of the first ICU within the CLASSIFY network represents an important milestone for the study. In an environment where critically ill patients require continuous assessment and rapid clinical decision-making, the ICU brings a particularly relevant perspective to research focused on sepsis.
Where critical care meets sepsis research
Led by Athina Lavrentieva, MD, PhD, Director and Anesthesiologist–Intensivist, the 1st ICU has extensive experience in the management of critically ill patients, including those requiring advanced organ support and intensive monitoring.
This expertise creates a strong connection with the objectives of CLASSIFY, where the timely identification and characterization of patients with sepsis are central to the study.
A new dimension for the CLASSIFY network
With the activation of the G. Papanikolaou General Hospital ICU on 10 September 2026, CLASSIFY expanded beyond Internal Medicine settings to include the perspective of Intensive Care Medicine.
The participation of Dr Lavrentieva and her team strengthens the multidisciplinary character of the study and adds critical care expertise to a growing network united by a common goal: advancing the understanding of sepsis through collaborative clinical research.
CLASSIFY. Different clinical settings. One shared mission against sepsis.
