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COVID-19Phase 3BIRCHNCT05603143

Study of Obeldesivir in Participants With COVID-19 Who Have a High Risk of Developing Serious or Severe Illness

A Phase 3 study testing Obeldesivir in people with COVID-19, run by Gilead Sciences at 81 sites in 18 countries.

Terminated

Stopped early. The study ended before it was planned to and will not resume.

Official record
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Trial summary

The goal of this clinical study is to test how well the study drug, obeldesivir (GS-5245), works and how safe it is in treating coronavirus disease 2019 (COVID-19) in participants that have a higher risk of getting a serious illness. Read more about this study

Who is it for?
Ages 18 years and older
Conditions the study is for
COVID-19
What is being tested?
Obeldesivir
Type of treatment
Pill or oral medicine
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
468 participants
Where
81 sitesin 18 countries
Study dates
5 Nov 2022to 7 Nov 2023
Phase
Phase 3
Are there results?
Yes, posted in the registrySummary in the doctors' view

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 18 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • Willing and able to provide written informed consent.
  • Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection confirmed by PCR or an approved alternative assay (eg. Rapid Antigen Test) ≤ 5 days before randomization. Serologic tests will not be accepted.
  • Initial onset of COVID-19 signs/symptoms ≤ 5 days before randomization.
  • Not currently hospitalized or requiring hospitalization.
  • Presence of ≥ 1 risk factor (if unvaccinated) or ≥ 2 risk factors (if vaccinated at any point) for progression to severe disease.

Who cannot join

  • Anticipated use of COVID-19 therapies during the current COVID-19 illness.
  • Received any direct acting antiviral drug against SARS-CoV-2 for the treatment of COVID-19 < 28 days or < 5 half-lives, whichever is longer, before randomization.
  • Anticipated need for hospitalization < 48 hours after randomization.
  • New oxygen requirement < 24 hours before randomization.
  • Decompensated cirrhosis (Child-Pugh class B or C) or acute liver injury/failure.
  • Undergoing dialysis, or history of moderate to severe renal impairment.
Show all 10Show fewer
  • Pregnant or breastfeeding (nursing).
  • Unwilling to use protocol-mandated birth control.
  • Received an approved, authorized or investigational COVID-19 vaccine (including booster dose) <120 days before randomization.
  • Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Trial locations and contacts

81 sites in 18 countries.

81 sites in 18 countries

Bulgaria18 sites

  • Multiprofile Hospital for Active Treatment Puls AD, Department of Internal Diseases

    Blagoevgrad, 2700

  • Medical Center Asklepii OOD

    Dupnitsa, 2600

  • Specialìzed Hosp¡tal for Active Trealment of Pneumophthisiatric Diseases Haskovo EOOD, Department of pneumology and phthisiatry

    Haskovo, 6300

  • Medical Center Zdrave-1 OOD

    Kozloduy, 3320

  • Diagnostic Consultative Center 1 - Lon EOOD

    Lom, 3600

  • Medical Center Hera EOOD, Montana

    Montana, 3400

  • Multiprofile Hospital for Active Treatment Dr. Stamen Iliev AD, Department of Pneumology Phthisiatrics

    Montana, 3400

  • Medical Center Medconsult Pleven OOD

    Pleven, 5800

  • Diagnostic Consultative Center Sveti Georgi EOOD

    Plovdiv, 4000

  • MHAT Sveta Karidad EAD, First Department of Anesthesiology and Intensive Care

    Plovdiv, 4004

  • Multiprofile Hospital for Active Treatment Sveti Panteleymon EOOD, First Department of Internal Diseases

    Plovdiv, 4004

  • Medical Center Prolet EOOD

    Rousse, 7002

  • Multiprofile Hospital for Active Treatment - Samokov EOOD, Department of Internal Diseases

    Samokov, 2000

  • Medical Center Unimed EOOD

    Sevlievo, 5400

  • Diagnostic and Consulting Center Aleksandrovska EOOD

    Sofia, 1431

  • Medical Center Hera EOOD

    Sofia, 1510

  • Diagnostic Consultative Center XX - Sofia EOOD

    Sofia, 1618

  • Specialized Hospital for Active Treatment of Pneumophthisiatric Diseases-Vratsa EOOD, Department of Pneumology

    Vratsa, 3000

Other trials in Bulgaria

Spain12 sites

  • Hospital Universitario Virgen de Las Nieves.

    A Gudiña, 32540

  • Hospital General Universitario Dr. Balmis

    Alicante, 3010

  • Hospital Universitari Germans Trias i Pujol

    Badalona, 08916

  • CAP La Mina

    Barcelona, 8007

  • Hospital HM Nou Delfos

    Barcelona, 8023

  • Hospital Universitario Virgen del Rocio

    Las Cabezas de San Juan, 41730

  • Hospital Universitario Infanta Leonor

    Madrid, 28031

  • Hospital Clinico San Carlos

    Madrid, 28040

  • Hospital Universitario Puerta de Hierro - Majadahonda

    Majadahonda, 28222

  • Hospital General Universitario Reina Sofia

    Murcia, 30003

  • Hospital Universitario Son Espases

    Palma de Mallorca, 07120

  • Hospital Universitaro y Politecnico La Fe

    Valencia, 46016

Other trials in Spain

Mexico8 sites

  • Panamerican Clinical Research Mexico S.A. de C.V.

    Col. El Salitre Juriquilla, 13030

  • Neurociencias Estudios Clinicos S.C.

    Culiacan Sinaloa, 80020

  • PanAmerican Clinical Research Mexico S.A de C.V.

    Guadalajara, 44670

  • EME RED Hospitalaria

    Mérida, 97000

  • Kohler & Milstein Research S.A de C.V.

    Mérida, 97070

  • Clinstile, S.A. De C.V.

    Mexico City, 06700

  • Oaxaca Site Management Organization S.C.

    Oaxaca City, 68000

  • FAICIC S. de R.L. de C.V.

    Veracruz, 91900

Other trials in Mexico

South Africa8 sites

  • Madibeng Centre for Research

    Brits, 0250

  • Clinresco Centres (Pty) Ltd

    City of Johannesburg, 1619

  • Synapta Clinical Research Centre

    Durban, 4001

  • Perinatal HIV Research Unit (PHRU)

    Johannesburg, 2013

  • Global Clinical Trials

    Pretoria, 0001

  • Jongaie Research

    Pretoria West, 0183

  • Limpopo Clinical Research Initiative

    Thabazimbi, 0380

  • FCRN Clinical Trial Centre (Pty) Ltd

    Vereeniging, 1938

Other trials in South Africa

Taiwan5 sites

  • Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation

    Hualien City, 970

  • China Medical University Hospital

    Taichung, 40447

  • National Taiwan University Hospital

    Taipei, 100

  • Tao-Yuan General Hospital

    Taoyuan City, 320

  • Kaohsiung Veterans General Hospital

    Zuo Ying Qu, 813

Other trials in Taiwan

Brazil3 sites

  • Faculdade de Medicina da Universidade Federal de Minas Gerais

    Belo Horizonte - MG, 30130-100

  • L2iP Instituto de Pesquisas Clínicas

    Brasília - DF, 70200-730

  • Centro de Pesquisa Clinica da Universidade Municipal de São Caetano do Sul (USCS)

    São Caetano Do Sul - SP, 09530-905

Other trials in Brazil

Canada3 sites

  • Hamilton Medical Research Group

    Hamilton, L8M 1K7

  • Dr. Anil K. Gupta Medicine Professional Corporation

    Toronto, M9V 4B4

  • Vancouver ID Research and Care Centre Society

    Vancouver, V6Z 2C9

Other trials in Canada

Japan3 sites

  • IUHW Narita Hospital

    Chibaken, 286-0124

  • Okayama University Hospital

    Okayama, 700-8558

  • Suita Municipal Hospital

    Suita, 564-8567

Other trials in Japan

Poland3 sites

  • ClinMedica Research

    Skierniewice, Łódź Voivodeship, 96-100

  • Ginemedica OVO 21

    Wroclaw, 50414

  • ETG Lodz

    Zgierz, 95-100

Other trials in Poland

Portugal3 sites

  • Hospital CUF Descobertas

    Lisbon, 1998-018

  • Centro Hospitalar de Entre Douro e Vouga - Hospital de Sao Sebaststiao

    Santa Maria da Feira, 4520-211

  • Hospital da Luz - Arrabida

    Vila Nova de Gaia, 4099-346

Other trials in Portugal

Romania3 sites

  • "Prof. Dr. Matei Bals" National Institute for Infectious Diseases

    Bucharest, 021105

  • County Hospital Caracal

    Caracal, 235200

  • Sibiu Emergency Clinical County Hospital

    Sibiu, 550253

Other trials in Romania

South Korea3 sites

  • ChungNam National University Hospital

    Daejeon, 35015

  • Chonnam National University Bitgoeul Hospital

    Gwangju, 61748

  • Korea University Guro Hospital

    Seoul, 152-703

Other trials in South Korea

United Kingdom3 sites

  • Ormeau Clinical Trials Limited

    Belfast, BT7 2EB

  • Lakeside Healthcare

    Corby, NN17 2UR

  • CPS Research

    Glasgow, G20 0XA

Other trials in United Kingdom

France2 sites

  • CHU de Montpellier-Hopital La Colombiere

    Montpellier, 34090

  • Hopital Pitie Salpetriere

    Paris, 75651

Other trials in France

Hungary1 site

  • Debreceni Egyetem Klinikai Kozpont

    Debrecen, 4031

Other trials in Hungary

Italy1 site

  • Unita Operativa Di Malattie Infettive Ospedale San Raffaele S.r.l.

    Milan, 20127

Other trials in Italy

Singapore1 site

  • National Centre for Infectious Diseases, Tan Tock Seng Hospital

    Singapore, 308433

Other trials in Singapore

Turkey (Türkiye)1 site

  • Acibadem University School of Medicine Atakent Hospital

    Trabzon, 61030

Other trials in Turkey (Türkiye)

About this study

Official title: A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of GS-5245 for the Treatment of COVID-19 in Participants With High-Risk for Disease Progression

The goal of this clinical study is to test how well the study drug, obeldesivir (GS-5245), works and how safe it is in treating coronavirus disease 2019 (COVID-19) in participants that have a higher risk of getting a serious illness.

Conditions
COVID-19
Being tested
Obeldesivir, Obeldesivir Placebo
Medical subject headings
COVID-19

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • ObeldesivirDrug

    Also called GS-5245

    Tablets administered orally without regard to food.

  • Obeldesivir PlaceboDrug

    Placebo tablets administered orally without regard to food.

Study groups in NCT05603143
Study groupRoleWhat they receive
ObeldesivirExperimentalParticipants will receive obeldesivir 350 mg orally twice daily for 5 days.
Receives: Drug: Obeldesivir
PlaceboPlacebo comparatorParticipants will receive placebo-to-match obeldesivir orally twice daily for 5 days.
Receives: Drug: Obeldesivir Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Percentage of Participants With Coronavirus Disease 2019 (COVID-19) Related Hospitalization or All-Cause Death by Day 29

    COVID-19-related hospitalization was defined as ≥ 24 hours of acute care for a reason related to COVID-19, in a hospital or similar acute care facility, including emergency rooms or temporary facilities instituted to address medical needs of those with COVID-19. This included specialized acute medical care units within an assisted living facility or nursing home. This did not include hospitalization for the purposes of public health and/or clinical trial execution. The date and duration of hospital admission, and primary reason for hospitalization (including if the hospitalization was related to COVID-19) were recorded. Percentages were rounded off.

    Measured: Up to Day 29

Secondary outcomes (10)

  1. Percentage of Participants With Treatment-Emergent Adverse Events (TEAE)

    TEAEs were defined as 1 or both of the following:

    Any AEs with an onset date on or after the study drug start date and no later than 30 days after permanent discontinuation of study drug. Any AEs leading to premature discontinuation of study drug. Percentages were rounded off.

    Measured: First dose date up to 5 Days plus 30 Days

  2. Percentage of Participants Experiencing Laboratory Abnormalities

    Treatment-emergent laboratory abnormalities were defined as values that increase at least 1 toxicity grade from baseline at any postbaseline time point, up to and including the date of last dose of study drug plus 30 days. Percentages were rounded off.

    Measured: First dose date up to 5 Days plus 30 Days

  3. Percentage of Participants Experiencing Serious Adverse Events (SAEs) and Adverse Events (AEs) Leading to Study Drug Discontinuation

    A treatment emergent AE is defined as an AE that occurs or worsens in severity on or after the date of the first dose of study drug but no later than 30 days after the permanent discontinuation of study drug or an AE leading to discontinuation of study drug. A SAE is defined as an event that, at any dose, resulted in any of the following: death, life-threatening, in-patient hospitalization or prolongation of existing hospitalization, persistent or significant disability/incapacity, a congenital anomaly/birth defect, or a medically important event or reaction. Percentages were rounded off.

    Measured: First dose date up to 5 Days plus 30 Days

  4. Percentage of Participants With All-Cause Hospitalization by Day 29

    All-cause hospitalization was defined as ≥ 24 hours of acute care, in a hospital or similar acute care facility, including emergency rooms or temporary facilities instituted to address medical needs of those with COVID-19. This includes specialized acute medical care units within an assisted living facility or nursing home. This does not include hospitalization for the purposes of public health and/or clinical study execution. The date and duration of hospital admission, and primary reason for hospitalization (including if the hospitalization is related to COVID-19) were recorded. Percentages were rounded off.

    Measured: Up to Day 29

  5. Percentage of Participants With COVID-19-Related Medically Attended Visits (MAVs) or All-Cause Death by Day 29

    Medically attended visits were defined as interactions with health care professionals other than study staff or designees including hospitalization; in-person emergency, urgent, or primary care visits; or any other in-person visit attended by the participant and a health care professional. The nature and cause of the visit were identified. KM estimates were used in the outcome measure analysis. Percentages were rounded off.

    Measured: Up to Day 29

  6. Percentage of Participants With COVID-19-Related MAVs by Day 29

    Medically attended visits were defined as interactions with health care professionals other than study staff or designees including hospitalization; in-person emergency, urgent, or primary care visits; or any other in-person visit attended by the participant and a health care professional. The nature and cause of the visit were identified. KM estimates were used in the outcome measure analysis. Percentages were rounded off.

    Measured: Up to Day 29

  7. Percentage of Participants With All-cause Death by Day 29

    Percentages were rounded off.

    Measured: Up to Day 29

  8. Time to COVID-19 Symptom Alleviation by Day 15

    Time to COVID-19 symptom alleviation was calculated as symptom alleviation date/time minus the first dose date/time. Symptom alleviation was evaluated for the 15 targeted symptoms using symptoms of infection with coronavirus-19 (SIC) questionnaire. The SIC questionnaire assessed all targeted symptoms, alleviation was defined as the SIC rating of 0, or at least 3 points decrease in rating from baseline, or an answer "No" to the question for at least 48 consecutive hours.

    Measured: Up to Day 15

  9. Change From Baseline in Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Nasal Swab Viral Load at Day 5

    The mixed model for repeated measures (MMRM) was used for analysis.

    Measured: Day 5

  10. Plasma Concentrations of GS-441524 (Metabolite of Obeldesivir)

    Measured: Day 1, 0.75 and 2 hours postdose and Day 5 predose and 0.75 hours postdose

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted2 Nov 2022
  2. Study start5 Nov 2022
  3. Primary completion7 Nov 2023
  4. Study completion7 Nov 2023

Why it stopped: The study was stopped early as it was determined there would not be a statistically significant treatment effect associated with the primary endpoint due to the low number of events.

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Masking
Double blind
Who is masked
Participant, Investigator
Enrolment
468 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05603143
Sponsor's protocol ID
GS-US-611-6273
Other IDs
2022-002741-18
Acronym
BIRCH
Status last verified
Dec 2024
First submitted
31 Oct 2022
Last updated
20 Dec 2024
Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
No

Publications

  • Hedskog C, Rodriguez L, Hu Y, Li J, Han D, Peinovich N, Martinez C, Ho PY, Perry JK, Gonzalez Del Castillo JM, Koullias Y, Martin R, Hyland RH. SARS-CoV-2 resistance analyses from the Phase 3 BIRCH study of obeldesivir in high-risk nonhospitalized participants with COVID-19. Antiviral Res. 2026 Mar;247:106351. doi: 10.1016/j.antiviral.2026.106351. Epub 2026 Jan 19.

    PubMed 41565160

  • Streinu-Cercel A, Castagna A, Chang SC, Chen YS, Koullias Y, Mozaffarian A, Hyland RH, Humeniuk R, Caro L, Davies S, Rodriguez L, Hedskog C, Chen S, Etchevers K, Behenna-Renton N, Llewellyn J, Osinusi A, Duff F, Barrat Hernandez A, McNally D, Simon-Campos JA, Leal FE, Fouche LF, Gonzalez Del Castillo JM. Efficacy and Safety of Obeldesivir in High-Risk Nonhospitalized Patients With COVID-19 (BIRCH): A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study. Clin Infect Dis. 2026 Feb 9;82(1):e24-e32. doi: 10.1093/cid/ciaf406.

    PubMed 40694627

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Obeldesivir in people with COVID-19, run by Gilead Sciences at 81 sites in 18 countries.

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 5 inclusion and 10 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: stopped early, as of the sponsor's last update on 20 Dec 2024. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 81 sites in Bulgaria, Spain, Mexico, South Africa, Taiwan and 13 more countries. 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. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

Yes. Results are posted in the registry (first posted 20 Dec 2024). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Percentage of Participants With Coronavirus Disease 2019 (COVID-19) Related Hospitalization or All-Cause Death by Day 29 (time frame: Up to Day 29). 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 NCT05603143, which also lists 2 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 20 Dec 2024.

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