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Efficacy of Azithromycin Plus Doxycycline Versus Doxycycline Plus Placebo in Patients With Rocky Mountain Spotted Fever

Efficacy of Azithromycin Plus Doxycycline Compared to Doxycycline Plus Placebo in Patients With Rocky Mountain Spotted Fever in Hospital General de Mexicali of ISESALUD and Hospital General No. 30 Instituto Mexicano Del Seguro Social

Status
UNKNOWN
Phases
Phase 3
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05398055
Acronym
Rocky-Z
Enrollment
86
Registered
2022-05-31
Start date
2022-05-12
Completion date
2025-12-31
Last updated
2022-05-31

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

Conditions

Rocky Mountain Spotted Fever

Keywords

Rocky Mountain Spotted Fever, Azithromycin, Doxycycline

Brief summary

The aim of this study is to impove the pharmacological treatment of Rocky mountain spotted fever, since is a very ancient disease with an antibiotic therapy that have not changed much the mortality rates, being compared with the natural curse of the disease.

Detailed description

Rocky mountain spotted fever is a potentially fatal infectious disease wich is transmitted trough vectors. This particular infection is caused by Rickettsia rickettsii wich is a gramnegative intracellular bacilli. The pathophysiological mechanism and clinical manifestation is mainly due to the vascular affectation, since this pathogen has a tropism for endothelial cells. As it has been mentioned, this is an obligate intracellular pathogen, so the main choice with the antibiotic therapy is tetracyclines because of its action mechanism in the inhibition of the subunit 30S. The objective of the study is to prove new strategies of treatment to improve the pharmacological aproach by implementing Azithromycin, wich is a macrolide that inhibits de 50S subunit of the bacteria. Azithromycin has shown effectivity against other rickettsial diseases.

Interventions

DRUGAzithromycin + Doxycycline

azithromycin 500 mg orally every 24 hours for three dose plus doxycycline 100 mg orally every 12 hours for 7 days

DRUGPlacebo + Doxycycline

doxycycline 100 mg orally every 12 hours for 7 days plus placebo 1 capsule every 24 hours, 3 doses

Sponsors

Hospital General de Mexicali
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
TRIPLE (Subject, Caregiver, Investigator)

Masking description

Patients will be randomized through the program ¨Randomizer for Clinical Trial¨ to be assigned in group of treatment A or B. One of the treatments will be azithromycin 500 mg orally every 24 hours for three dose plus doxycycline 100 mg orally every 12 hours for 7 days and the other schedule it will be doxycycline 100 mg orally every 12 hours for 7 days plus placebo 1 capsule every 24 hours, 3 doses.

Intervention model description

Controlled randomized trial with placebo, triple blinded, multicenter study

Eligibility

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

Inclusion criteria

* Any gender * Over 18 years old * hospitalized in the internal medicine service, emergency department or intensive care unit of Hospital General de Mexicali (ISESALUD) or Hospital General Zona No. 30 (IMSS) with suspicion of RMSF that present fever and 2 or more of the next symptoms: headache, myalgia, rash, nausea, pharyngeal hyperemia, vomiting, abdominal pain, neurological disorders. * In addition to at least one of the next epidemiologycal fators: presence of vectors in areas of residence or endemic areas visited two weeks prior to the onset of symptoms, history of visiting or residing in areas with RMSF transmission in the last two weeks, existence of confirmed cases in the locality of origin, history of vector bite or contact with dogs in the two weeks.

Exclusion criteria

* Other clinical suspicion rather than RMSF * History of allergy to doxycycline, azithromycin, bean starch or bovine gelatin. * Not signing the informed consent * Pregnancy.

Design outcomes

Primary

MeasureTime frame
Mortality of azithromycin plus doxycycline vs doxycycline plus placebo3 years

Secondary

MeasureTime frame
Number of hospitalization days in each arm3 years
Number of participants with renal replacement therapy.3 years
Number of participants that required amines in both groups.3 years
Number of fever days in both arms.3 years

Countries

Mexico

Contacts

Primary ContactHiram J. Jaramillo-Ramirez, MD
grupoinvestigacionmedica@gmail.com686 135 8412
Backup ContactGisel V. Licon-Martinez, MD
viviana.licon@uabc.edu.mx686 194 5903

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026