COVID-19NCT05504057
Antihistamines, Amantadine and Evolution of COVID-19
An observational study of COVID-19, run by Consorci Sanitari de Terrassa at 2 sites in Spain.
Trial summary
The rates of symptomatic COVID19 infection, hospital admission among COVID19 cases and survival would be quantified in patiens chronically treated with antihistamines or amantadine, with the aim of determining the role of antihistamines and amantadine in the evolution of COVID19. Read more about this study
- Who is it for?
- Any ageHealthy volunteers can take part
- Conditions the study is for
- COVID-19
- What is being tested?
- Antihistamine and Amantadine
- How many people
- 140,660 participants
- Where
- 2 sitesSpain
- Study dates
- 1 Mar 2020to 24 Feb 2028
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages Any age
- All sexes
- Healthy volunteers accepted
- Child, Adult, Older adult
Study population: Population assigned to the Public and free Access Terrassa Health Consortium
Who may be able to join
None listed.
Who cannot join
- -
Trial locations and contacts
2 sites in 1 country. Contact the study team or a site near you to ask about taking part.
Spain2 sites, 2 recruiting
- Recruiting
Hospital de Terrassa
Terrassa, Barcelona, 08227
Anna Puigdellívol-Sánchez, Ph.D., 34-93-5884555, apuigdellivol@cst.cat
- Recruiting
Hospital of Terrassa
Terrassa, Barcelona, 08227
Anna Puigdellívol, PhD
About this study
Official title: Evaluation of Treatments With Antihistamines and Amantadine in the Evolution of the SARS-CoV-2 Infection
The rates of symptomatic COVID19 infection, hospital admission among COVID19 cases and survival would be quantified in patiens chronically treated with antihistamines or amantadine, with the aim of determining the role of antihistamines and amantadine in the evolution of COVID19.
Read the detailed description
BACKGROUND: According to previous reports, all 84 eldery residents in nuersing homes in Yespes (Toledo, Spain), had a 100% of positive serology for COVID-19 in June 2020, but none died nor hospitalized after receiving early treatment with antihistamines. Other case reports have suggested a protective role of amantadine, since infected patients showed a very mild COVID19 infection.
OBJECTIVES.Determine the role of antihistamines and amantadine in the evolution of COVID19.
METHODS. Describe the rate of hospitalization, ICU, survival, postcovid syndrome and thrombosis among COVID 19 cases having antihistamines and amantadine as chronic treatments.
The rates would be stratified by age groups and compared with the same age groups of the population assigned to the public free Access Terrassa Health Consortium.
- Conditions
- COVID-19
- Being tested
- Antihistamine, Amantadine
- Keywords
- antihistamines, amantadine, hospital admissions, survival
- Medical subject headings
- COVID-19
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
AntihistamineDrug
Also called Antihistamine as crhonic treatment and COVID19 infection.
Observation of the rate of COVID19 infection, the rate of hospitalization, the rate of survival and postcovid syndrome and thrombosis among patients previously treated with antihistamines
AmantadineDrug
Also called Amantadine as chronic treatment and COVID19 infection.
Observation of the rate of COVID19 infection, the rate of hospitalization, the rate of survival and the rate of postcovid syndrome and thrombosis among patients previously treated with amantadine
| Study group | Role | What they receive |
|---|---|---|
| Patients with chronic treatment with antihistamines or amantadine | The % of patients having antihistamines or amantadine as chronic treatment that suffered COVID would be compared to the population of the Terrassa Health Consortium (THC) of the same age groups. Receives: Drug: Antihistamine; Drug: Amantadine | |
| Other population of the THC | The % of patients of the Terrassa Health Consortium that suffered COVID19 infection of the same age groups. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Hospital Admissions.
Rate of Hospitalization among COVID 19 infections
Measured: from march 2020.
Secondary outcomes (4)
Survival
Survival among COVID1 hospitalized cases.
Measured: from march 2020
Symptomatic infection
Patients suffering a symptomatic COVID19 infection within a determinate age group
Measured: from march 2020
Postcovid syndrome
Patients developing postcovid syndrome after COVID19 infection
Measured: from april 2020
Thrombosis
Patients developing thrombosis (with particular assessment of stroke, cardiac infarction, retinal vessels and pulmonary embolism)
Measured: from april 2020
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Aug 2022
- Study start1 Mar 2020
- Primary completion19 Jan 2025
- Study completion24 Feb 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (5)Papers the sponsor has linked to this study.
- Other trials for COVID-19Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case-control
- Time perspective
- Retrospective
- Enrolment
- 140,660 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Consorci Sanitari de Terrassa
- Sponsor type
- University, hospital or other
- Collaborators
- Institut Català de la Salut
- Responsible party
- Principal investigator, Anna Puigdellívol-Sánchez, Consorci Sanitari de Terrassa
- Investigators
- Anna Puigdellívol, PhD, Principal investigator, Terrassa Health Consortium
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05504057
- Sponsor's protocol ID
- 02-22-161-060
- Status last verified
- Mar 2026
- First submitted
- 15 Aug 2022
- Last updated
- 3 Apr 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- Undecided: Once the papers related to the study are published, a statement will be included offering data when contacting with the authors.
Publications
Moran Blanco JI, Alvarenga Bonilla JA, Homma S, Suzuki K, Fremont-Smith P, Villar Gomez de Las Heras K. Antihistamines and azithromycin as a treatment for COVID-19 on primary health care - A retrospective observational study in elderly patients. Pulm Pharmacol Ther. 2021 Apr;67:101989. doi: 10.1016/j.pupt.2021.101989. Epub 2021 Jan 16.
PubMed 33465426Cortes-Borra A, Aranda-Abreu GE. Amantadine in the prevention of clinical symptoms caused by SARS-CoV-2. Pharmacol Rep. 2021 Jun;73(3):962-965. doi: 10.1007/s43440-021-00231-5. Epub 2021 Feb 18.
PubMed 33604795Puigdellivol-Sanchez A, Juanes-Gonzalez M, Calderon-Valdiviezo A, Losa-Puig H, Valls-Foix R, Gonzalez-Salvador M, Lozano-Paz C, Vidal-Alaball J. COVID-19 in Relation to Chronic Antihistamine Prescription. Microorganisms. 2024 Dec 13;12(12):2589. doi: 10.3390/microorganisms12122589.
PubMed 39770791Puigdellivol-Sanchez A, Juanes-Gonzalez M, Calderon-Valdiviezo A, Valls-Foix R, Gonzalez-Salvador M, Lozano-Paz C, Vidal-Alaball J. COVID-19 in Relation to Polypharmacy and Immunization (2020-2024). Viruses. 2024 Sep 27;16(10):1533. doi: 10.3390/v16101533.
PubMed 39459868Puigdellivol-Sanchez A, Arevalo-Genicio A, Garcia-Arque MC, Gragea-Nocete M, Lozano-Paz C, Moro-Casasola V, Perez-Diaz C, Valls-Foix R, Roca-Puig R, Llistosella M. Long COVID and Reduced Thrombosis in Antihistamine-Treated Patients: An Observational Study in the Metropolitan Area of Barcelona. Viruses. 2026 Feb 2;18(2):197. doi: 10.3390/v18020197.
PubMed 41754542
Study at a glance
From the registry record, last updated by the sponsor on 3 Apr 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluation of Treatments With Antihistamines and Amantadine in the Evolution of the SARS-CoV-2 Infection
- ClinicalTrials.gov ID
- NCT05504057
- Acronym / sponsor ID
- 02-22-161-060
- Conditions
- COVID-19
- Keywords
- antihistamines, amantadine, hospital admissions, survival
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 140,660 participants (estimated)
- Lead sponsor
- Consorci Sanitari de TerrassaUniversity, hospital or other
- Collaborators
- Institut Català de la Salut
- Study start
- 1 Mar 2020 (actual)
- Primary completion
- 19 Jan 2025 (actual)
- Study completion
- 24 Feb 2028 (estimated)
- First posted
- 17 Aug 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The rates of symptomatic COVID19 infection, hospital admission among COVID19 cases and survival would be quantified in patiens chronically treated with antihistamines or amantadine, with the aim of determining the role of antihistamines and amantadine in the evolution of COVID19.
Detailed description
BACKGROUND: According to previous reports, all 84 eldery residents in nuersing homes in Yespes (Toledo, Spain), had a 100% of positive serology for COVID-19 in June 2020, but none died nor hospitalized after receiving early treatment with antihistamines. Other case reports have suggested a protective role of amantadine, since infected patients showed a very mild COVID19 infection.
OBJECTIVES.Determine the role of antihistamines and amantadine in the evolution of COVID19.
METHODS. Describe the rate of hospitalization, ICU, survival, postcovid syndrome and thrombosis among COVID 19 cases having antihistamines and amantadine as chronic treatments.
The rates would be stratified by age groups and compared with the same age groups of the population assigned to the public free Access Terrassa Health Consortium.
Study design
- Observational model
- Case-control
- Time perspective
- Retrospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Patients with chronic treatment with antihistamines or amantadine | – | Drug: Antihistamine, Drug: AmantadineThe % of patients having antihistamines or amantadine as chronic treatment that suffered COVID would be compared to the population of the Terrassa Health Consortium (THC) of the same age groups. |
| Other population of the THC | – | –The % of patients of the Terrassa Health Consortium that suffered COVID19 infection of the same age groups. |
Who may qualify
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Child, Adult, Older adult
- Study population
- Population assigned to the Public and free Access Terrassa Health Consortium
Key inclusion criteria (0 listed)
Key exclusion criteria (1 listed)
- -
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| AntihistamineAlso: Antihistamine as crhonic treatment and COVID19 infection.Observation of the rate of COVID19 infection, the rate of hospitalization, the rate of survival and postcovid syndrome and thrombosis among patients previously treated with antihistamines | Drug | Patients with chronic treatment with antihistamines or amantadine |
| AmantadineAlso: Amantadine as chronic treatment and COVID19 infection.Observation of the rate of COVID19 infection, the rate of hospitalization, the rate of survival and the rate of postcovid syndrome and thrombosis among patients previously treated with amantadine | Drug | Patients with chronic treatment with antihistamines or amantadine |
Primary outcome
Hospital Admissions.
Time frame: from march 2020.
Rate of Hospitalization among COVID 19 infections
4 secondary outcomes
Survival
Time frame: from march 2020
Symptomatic infection
Time frame: from march 2020
Postcovid syndrome
Time frame: from april 2020
Thrombosis
Time frame: from april 2020
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 3 Apr 2026.
- Background: PubMed 33465426Moran Blanco JI, Alvarenga Bonilla JA, Homma S, Suzuki K, Fremont-Smith P, Villar Gomez de Las Heras K. Antihistamines and azithromycin as a treatment for COVID-19 on primary health care - A retrospective observational study in elderly patients. Pulm Pharmacol Ther. 2021 Apr;67:101989. doi: 10.1016/j.pupt.2021.101989. Epub 2021 Jan 16.
- Background: PubMed 33604795Cortes-Borra A, Aranda-Abreu GE. Amantadine in the prevention of clinical symptoms caused by SARS-CoV-2. Pharmacol Rep. 2021 Jun;73(3):962-965. doi: 10.1007/s43440-021-00231-5. Epub 2021 Feb 18.
- Results publication: PubMed 39770791Puigdellivol-Sanchez A, Juanes-Gonzalez M, Calderon-Valdiviezo A, Losa-Puig H, Valls-Foix R, Gonzalez-Salvador M, Lozano-Paz C, Vidal-Alaball J. COVID-19 in Relation to Chronic Antihistamine Prescription. Microorganisms. 2024 Dec 13;12(12):2589. doi: 10.3390/microorganisms12122589.
- Results publication: PubMed 39459868Puigdellivol-Sanchez A, Juanes-Gonzalez M, Calderon-Valdiviezo A, Valls-Foix R, Gonzalez-Salvador M, Lozano-Paz C, Vidal-Alaball J. COVID-19 in Relation to Polypharmacy and Immunization (2020-2024). Viruses. 2024 Sep 27;16(10):1533. doi: 10.3390/v16101533.
- Results publication: PubMed 41754542Puigdellivol-Sanchez A, Arevalo-Genicio A, Garcia-Arque MC, Gragea-Nocete M, Lozano-Paz C, Moro-Casasola V, Perez-Diaz C, Valls-Foix R, Roca-Puig R, Llistosella M. Long COVID and Reduced Thrombosis in Antihistamine-Treated Patients: An Observational Study in the Metropolitan Area of Barcelona. Viruses. 2026 Feb 2;18(2):197. doi: 10.3390/v18020197.
- Individual participant dataSharing planned: Undecided. Once the papers related to the study are published, a statement will be included offering data when contacting with the authors.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Anna Puigdellívol, PhD principal investigator
Terrassa Health Consortium
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of COVID-19, run by Consorci Sanitari de Terrassa at 2 sites in Spain.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 0 inclusion and 1 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 3 Apr 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in Spain. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Anna Puigdellivol, Ph.D (34-93-5884555, apuigdellivol@cst.cat), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Hospital Admissions. (time frame: from march 2020.). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05504057, which also lists 5 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 3 Apr 2026.