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Rapid Empiric Treatment With Oseltamivir Study (RETOS)

Title: Effectiveness of Empiric Antiviral Treatment for Hospitalized Community Acquired Pneumonia During the Influenza Season (U18)

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01248715
Acronym
RETOS
Enrollment
1107
Registered
2010-11-25
Start date
2010-11-30
Completion date
2016-05-31
Last updated
2023-06-15

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Influenza, Pneumonia

Keywords

pneumonia, bacterial, pneumonia, viral, respiratory tract infections, oseltamivir, therapeutic use

Brief summary

Current guidelines recommend early initiation of empiric antibiotic therapy to cover typical and atypical bacteria that may cause community-acquired pneumonia (CAP). Influenza antiviral therapy in patients with suspected or confirmed influenza. However, many clinicians do not suspect influenza among patients with CAP or other acute lower respiratory tract illness (LRTI) and often do not test for influenza. Additionally, results from currently available diagnostic tests for influenza may be delayed and several tests have low sensitivity and will give false negative results. Thus, anti-influenza treatment for patients with hospitalized influenza CAP and LRTI is frequently initiated late if at all. There is an association between delayed time to administration of empiric antibiotic therapy with increased clinical failure and mortality. As a result, empiric antibiotic therapy for patients with suspect CAP is begun within 4 - 6 hours of hospitalization. This has recently been demonstrated for delayed antiviral treatment as well. We hypothesize that, as happens with early empiric antibiotics for bacterial CAP, a standardized approach of adding early empiric anti-influenza therapy during the influenza season to hospitalized patients with suspect CAP and LRTI will improve clinical outcomes of patients with influenza associated CAP and LRTI. To test our hypothesis we plan a prospective, randomized, multicenter clinical trial of hospitalized patients with acute LRTI, including suspect CAP, during . If early anti-influenza medications were not included on the patients admission orders, patients will be randomized to standard care, including empiric antibacterial therapy as recommended by ATS/IDSA guidelines plus standard influenza diagnostics and treatment (Standard of care) versus early initiation of empiric antiinfluenza therapy plus standard care, e.g. empiric antibacterial (oseltamivir group). The primary study outcome will be development of clinical failure and selected clinical outcomes during the 30 days after enrollment. Other clinical outcomes that will be compared between study groups include time to clinical stability, duration of hospitalization, development of cardiovascular events, re-hospitalization, short-term mortality (30 days), and long-term mortality (1 year). The secondary study outcome will be the cost-effectiveness of the intervention.

Detailed description

This will be both a prospective, randomized, unblinded clinical study of hospitalized patients with acute LRTI admitted in one of four institutions in Louisville, KY (rapid empiric treatment with oseltamivir study\[RETOS\]) and a prospective observation study to describe influenza LRTI (Flu LRTI study). All hospitalized patients with acute LRTI will be invited to participate in one of the arms of study. If the admitting clinician does not order oseltamivir or zanamivir at the time of hospital admission, the patient is eligible for randomization into Group A (standard clinical care, including empiric antibiotics and anti-influenza drugs at the clinician discretion) or Group B (oseltamivir administered to the patient within 24 hours of admission, ideally within 8-12 hours of admission, plus empiric antibiotics). Patients will be enrolled from one of four hospitals, the University of Louisville Hospital, Veterans Affairs Medical Center of Louisville, Norton Hospital of Louisville, and Jewish Hospital of Louisville. Eligible patients will be identified primarily in the Emergency Departments of all four hospitals and evaluated for inclusion/exclusion criteria after hospital admission orders are written. Patients will be enrolled only during the influenza season. For this study, the influenza season is defined as December 1st until May 1st, unless surveillance data suggests that influenza viruses are circulating earlier or have stopped circulating. For all three study groups, diagnosis of influenza will be based on nucleic acid amplification through polymerase chain reaction (PCR). At the time of enrollment into the study, a nasopharyngeal swab will be obtained for PCR. The University of Louisville Infectious Diseases Reference Laboratory has extensive experience using molecular techniques for the diagnosis of respiratory pathogens and will test batched specimens at monthly intervals. In addition, we will collect the results from tests done for routine care and bacterial or virus isolates identified during routine care for further characterization. The management of patients in Group A and Group B will be different only in regard to early empiric anti-influenza therapy. All other aspects of the management of these patients will be in compliance with national guideline recommendations from IDSA/ATS (2). Patients in Group A may have antiviral therapy started later in hospitalization or not treated at all. The study will not interfere with Group A patient care. A 1:1 randomization ratio within the two study arms is planned for EOS. A pre-defined randomization chart will be designed in order to have the randomization process Internet-based. The randomization table will be accessible by the project manager as a back up in the event that any problem occurs with the Internet or the computerized system. We will attempt to begin oseltamivir within 8 - 12 hours after hospital admission, and no later than 24 hours. The study nurse will facilitate receipt of early oseltamivir treatment for the consented patient in collaboration with the hospital pharmacies. The time of oseltamivir administration will be recorded for all enrolled patients.

Interventions

DRUGoseltamivir

These patients will receive early (within 8-12 hours of admission, no later than 24 hours after admission) oseltamivir plus current, standard empiric antibacterial therapy based on national recommendations from the IDSA/ATS guidelines for management of hospitalized patients with CAP (2). Anti-influenza therapy will be given using oseltamivir at a dose of 75 mg twice daily. The oseltamivir dose will be adjusted in patients with renal insufficiency according to the package insert. Duration of antiviral therapy will be for a minimum of 5 days for patients with evidence of early clinical improvement and prolonged depending on clinical stability

Sponsors

Centers for Disease Control and Prevention
CollaboratorFED
University of Louisville
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

For oseltamivir and standard of care groups: * 18 years of age or older * No oseltamivir or zanamivir ordered in hospital admission orders * Meets criteria for acute LRTI * Signed informed consent.

Exclusion criteria

For oseltamivir and standard of care groups: * Oseltamivir or zanamivir ordered in hospital admission orders * Patients hospitalized for the LRTI for more than 24 hours before enrollment into the trial. * Patients with mental conditions who are unlikely to comply with the study protocol and who cannot give informed consent and have no guardian or proxy. * Patients who have had severe allergic reactions such as anaphylaxis or serious skin reactions such as toxic epidermal necrolysis, Stevens-Johnson syndrome, or erythema multiforme to any component of oseltamivir (TAMIFLU). * Prisoners

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With Clinical Failure (Failure to Reach Clinical Stability)7 daysNumber of subject that showed lack of clinical improvement within 7 days. Criteria for clinical improvement include no fever; white blood cell count decreases, or increases in the case of leukopenia, to more than 10% from the prior day; the evaluation of signs and symptoms of CAP to define when the patient is subjectively better, and the patient is able to tolerate food by mouth.
Number of Participants to Transfer to ICU After 24 h24 hNumber of subjects that were transfered to an intensive care unit (ICU) after 24 hours of hospitalization. A patient transferred to ICU within 24 hours of admission was considered as a direct admission to ICU and not meeting criteria for clinical failure.
Number of Participants That Required Re-hospitalization30 daysParticipants that were re-hospitalized within 30 days after enrollment.
Number of Participants That Had Short-term Mortality30 daysNumber of subjects who died within 30 days of enrollment

Secondary

MeasureTime frameDescription
Length of Hospital Staythrough study completion, up to 30 daysDuration of hospitalization calculated as the day of discharge minus the day of admission.
Number of Participants With Hospital Mortality.through study completion, up to 30 daysNumber of subjects who died while hospitalized
Days to Reach Clinical Stability30 daysTime to clinical improvement. The criteria for clinical improvement were followed during the first week from the day of admission and defined as follows: a) improvement of signs and symptoms of LRTI reported by patient b) afebrile for at least 8 hours, c) decrease in white blood cell count to more than 10% from the prior day, and d) able to tolerate oral feeding. A patient was considered clinically improved on the day that these four criteria were all met.

Countries

United States

Participant flow

Participants by arm

ArmCount
Oseltamirvir
These patients will receive early oseltamivir plus current, standard empiric antibacterial therapy. oseltamivir: These patients will receive early (within 8-12 hours of admission, no later than 24 hours after admission) oseltamivir plus current, standard empiric antibacterial therapy based on national recommendations from the IDSA/ATS guidelines for management of hospitalized patients with CAP (2). Anti-influenza therapy will be given using oseltamivir at a dose of 75 mg twice daily. The oseltamivir dose will be adjusted in patients with renal insufficiency according to the package insert. Duration of antiviral therapy will be for a minimum of 5 days for patients with evidence of early clinical improvement and prolonged depending on clinical stability
55
Standard of Care
These patients will be treated with the current, standard care, including currently recommended antibiotics or antiviral therapy based on national recommendations from the IDSA/ATS guidelines for management of hospitalized patients with CAP and ACIP antiviral use guidelines for hospitalized patients with confirmed of suspect influenza, per clinician discretion. In addition these patients with have a NP swab collected for influenza PCR testing and clinical information will be extracted from the medical record.
41
Total96

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyNot influenza positive501510

Baseline characteristics

CharacteristicOseltamirvirStandard of CareTotal
Age, Continuous63 years60 years61.7 years
Nursing home Resident0 Participants2 Participants2 Participants
Region of Enrollment
United States
55 Participants41 Participants96 Participants
Sex: Female, Male
Female
23 Participants23 Participants46 Participants
Sex: Female, Male
Male
32 Participants18 Participants50 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
2 / 551 / 41
other
Total, other adverse events
0 / 550 / 41
serious
Total, serious adverse events
0 / 551 / 41

Outcome results

Primary

Number of Participants That Had Short-term Mortality

Number of subjects who died within 30 days of enrollment

Time frame: 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
OseltamirvirNumber of Participants That Had Short-term Mortality2 Participants
Standard of CareNumber of Participants That Had Short-term Mortality1 Participants
p-value: 0.9999Wilcoxon (Mann-Whitney)
Primary

Number of Participants That Required Re-hospitalization

Participants that were re-hospitalized within 30 days after enrollment.

Time frame: 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
OseltamirvirNumber of Participants That Required Re-hospitalization5 Participants
Standard of CareNumber of Participants That Required Re-hospitalization5 Participants
p-value: 0.732Wilcoxon (Mann-Whitney)
Primary

Number of Participants to Transfer to ICU After 24 h

Number of subjects that were transfered to an intensive care unit (ICU) after 24 hours of hospitalization. A patient transferred to ICU within 24 hours of admission was considered as a direct admission to ICU and not meeting criteria for clinical failure.

Time frame: 24 h

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
OseltamirvirNumber of Participants to Transfer to ICU After 24 h2 Participants
Standard of CareNumber of Participants to Transfer to ICU After 24 h2 Participants
p-value: 0.9999Wilcoxon (Mann-Whitney)
Primary

Number of Participants With Clinical Failure (Failure to Reach Clinical Stability)

Number of subject that showed lack of clinical improvement within 7 days. Criteria for clinical improvement include no fever; white blood cell count decreases, or increases in the case of leukopenia, to more than 10% from the prior day; the evaluation of signs and symptoms of CAP to define when the patient is subjectively better, and the patient is able to tolerate food by mouth.

Time frame: 7 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
OseltamirvirNumber of Participants With Clinical Failure (Failure to Reach Clinical Stability)6 Participants
Standard of CareNumber of Participants With Clinical Failure (Failure to Reach Clinical Stability)2 Participants
p-value: 0.46Wilcoxon (Mann-Whitney)
Secondary

Days to Reach Clinical Stability

Time to clinical improvement. The criteria for clinical improvement were followed during the first week from the day of admission and defined as follows: a) improvement of signs and symptoms of LRTI reported by patient b) afebrile for at least 8 hours, c) decrease in white blood cell count to more than 10% from the prior day, and d) able to tolerate oral feeding. A patient was considered clinically improved on the day that these four criteria were all met.

Time frame: 30 days

ArmMeasureValue (MEDIAN)
OseltamirvirDays to Reach Clinical Stability2 days
Standard of CareDays to Reach Clinical Stability2 days
p-value: 0.685Wilcoxon (Mann-Whitney)
Secondary

Length of Hospital Stay

Duration of hospitalization calculated as the day of discharge minus the day of admission.

Time frame: through study completion, up to 30 days

ArmMeasureValue (MEDIAN)
OseltamirvirLength of Hospital Stay4 days
Standard of CareLength of Hospital Stay4.5 days
p-value: 0.796Wilcoxon (Mann-Whitney)
Secondary

Number of Participants With Hospital Mortality.

Number of subjects who died while hospitalized

Time frame: through study completion, up to 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
OseltamirvirNumber of Participants With Hospital Mortality.1 Participants
Standard of CareNumber of Participants With Hospital Mortality.1 Participants
p-value: 0.9999Wilcoxon (Mann-Whitney)

Source: ClinicalTrials.gov · Data processed: Mar 14, 2026