Treatment Trials

2,178 Clinical Trials for Various Conditions

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COMPLETED
Evaluation of the AudibleHealth Dx AI/ML-Based Dx SaMD Using FCV-SDS in the Diagnosis of COVID-19 Illness: Clinical Validation
Description

The AudibleHealth Dx is a diagnostic software as a medical device (Dx SaMD) consisting of an ensemble of software subroutines that interacts with a proprietary database of Signal Data Signatures (SDS), using Artificial Intelligence/Machine Learning (AI/ML) to analyze forced cough vocalization signal data signatures (FCV-SDS) for diagnostic purposes. This study will evaluate the performance of the AudibleHealth Dx in comparison to a standard of care Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) test for the diagnosis of COVID-19. A secondary purpose of the study will be usability testing of the device for participants and providers.

COMPLETED
Evaluation of the AudibleHealth Dx AI/ML-Based Dx SaMD Using FCV-SDS in the Diagnosis of COVID-19 Illness
Description

The AudibleHealth Dx is a diagnostic software as a medical device (Dx SaMD) consisting of an ensemble of software subroutines that interacts with a proprietary database of Signal Data Signatures (SDS), using Artificial Intelligence/Machine Learning (AI/ML) to analyze forced cough vocalization signal data signatures (FCV-SDS) for diagnostic purposes. This study will evaluate the performance of the AudibleHealth Dx in comparison to a standard of care Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) test for the diagnosis of COVID-19. Bidirectional Sanger sequencing will be used to reduce the rate of false negative and false positive results. A secondary purpose of the study will be usability testing of the device for participants and providers.

Conditions
TERMINATED
Leidos-Enabled Adaptive Protocol (LEAP-CT) for Evaluation of Post-exposure Prophylaxis for Newly-infected COVID-19 Patients
Description

This study is designed to test the efficacy and safety of combinations of two well-understood agents - famotidine and celecoxib. Each of these agents separately demonstrate clinical activity in mitigating COVID-19 disease symptoms or severity, and each of which appear to have separate and complementary mechanisms of action.

ACTIVE_NOT_RECRUITING
LEAP-CT for Treatment of COVID-19 Patients (Master Protocol)
Description

This master protocol serves as a common reference for the inpatient and outpatient clinical studies that share common elements.

TERMINATED
Safety and Efficacy of USB002 for Respiratory Distress Due to COVID-19
Description

This trial will study the use of USB002 given as an intravenous infusion in patients with respiratory distress due to infection with COVID-19.

WITHDRAWN
Utility of Empiric Antibiotics for Non-intubated Novel Coronavirus Diseases 2019 Patients
Description

This retrospective analysis of inpatient data obtained from administrative and electronic medical records will investigate the role of empiric antibiotics on admission on the mortality for non-intubated patients presenting with Novel Coronavirus Diseases 2019 (COVID-19) associated pneumonia without extra-pulmonary sources of infection or septic shock.

TERMINATED
Study to Evaluate Safety and Efficacy of Carrimycin for Treatment of Severe Coronavirus Disease 2019 (COVID-19) in Hospitalized Patients
Description

This is a randomized, multicenter, placebo-controlled, double-blind clinical study in patients hospitalized due to severe Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection.

TERMINATED
Losmapimod Safety and Efficacy in COVID-19
Description

The therapeutic hypothesis for the use of losmapimod in COVID-19 disease is that increased mortality and severe disease is caused by p38 mitogen-activated protein kinase (MAPK)-mediated exaggerated acute inflammatory response resulting from SARS-CoV-2 infection. The study Sponsor hypothesizes that the early initiation of p38α/β inhibitor therapy in patients hospitalized with moderate COVID-19 who are at increased risk of a poor prognosis based on older age and elevated systemic inflammation will reduce clinical deterioration including progression to respiratory failure and death. To address this hypothesis, Fulcrum Therapeutics is conducting a Phase 3, multicenter, randomized, double-blind, placebo-controlled study that will evaluate the safety and efficacy of losmapimod versus placebo in subjects 40 and older who are hospitalized with moderate COVID-19 disease.

Conditions
TERMINATED
Poractant Alfa (Curosurf®)) -- Effect in Adult Patients Diagnosed With 2019 Novel Coronavirus (SARS-COV-19; (Covid-19)) Acute Respiratory Distress Syndrome (ARDS)
Description

The purpose of this study was to evaluate the efficacy and safety of poractant alfa (Curosurf®), administered by endotracheal (ET) instillation in hospitalized adult patients diagnosed with SARS-COV-19 acute respiratory distress syndrome (ARDS).

TERMINATED
RAPA-501-Allo Therapy of COVID-19-ARDS
Description

The first-in-human Phase 1 study component will evaluate two dose levels of RAPA-501-ALLO off the shelf cells in patients with COVID-19-related ARDS, with key endpoints of safety, biologic and potential disease-modifying effects. The randomized, double-blind, placebo-controlled Phase 2b study component will evaluate infusion of RAPA-501 ALLO off the shelf cells or a control infusion, with the primary endpoint assessing whether RAPA-501 cells reduce 30-day mortality. The COVID-19 pandemic is a disaster playing out with progressive morbidity and mortality. As of April 6th, 2021, an estimated 132.1 million people have contracted the virus and 2,866,000 deaths have resulted globally. The United States has the highest totals with an estimated 30.8 million people diagnosed and 556,000 deaths. In stages 1 and 2 of COVID-19, viral propagation within the patient is predominant. As such, therapeutic interventions focus on immune molecules (convalescent serum, monoclonal antibodies) and anti-viral medications (remdesivir). In marked contrast, the most severe and deadly form of COVID-19, stage 3, is driven not by viral propagation, but by an out-of-control immune response (hyperinflammation) caused by increases in immune molecules known as cytokines and chemokines. As such, therapeutic interventions for stage 3 disease focus on anti-inflammatory medications such as anti-cytokine therapy (anti-IL-6 drugs) or corticosteroid therapy. Unfortunately, such interventions do not address the full pathogenesis of stage 3 COVID-19, which includes hyperinflammation due to "cytokine storm" and "chemokine storm," tissue damage, hypercoagulation, and multi-organ failure (including lung, heart, kidney and brain). The pulmonary component of stage 3 disease includes acute respiratory distress syndrome (ARDS), which is a final-common-pathway of patient death due to a myriad of conditions, including pneumonia, sepsis, and trauma. There is a dire need for novel cellular treatments that can deliver both a broad-based immune modulation effect and a tissue regenerative effect, such as RAPA-501-ALLO off-the-shelf allogeneic hybrid TREG/Th2 Cells. Stage 3 COVID-19 carries an estimated 30-day mortality of over 50% in spite of ICU utilization, mechanical ventilation, and supportive care therapies to manage ARDS and multiorgan failure. Narrowly acting targeted anti-inflammatory approaches such as anti-IL-6 therapeutics have not been particularly effective in stage 3 COVID-19 and the broad anti-inflammatory pharmaceutical approach of corticosteroid therapy, has only modestly tempered stage 3 disease in some studies. Cell therapy is also being evaluated in stage 3 COVID-19, in particular, mesenchymal stromal cells (MSC) and now, with the current RAPA-501-ALLO protocol, regulatory T (TREG) cells. TREG therapy has a mechanism of action that includes a multi-faceted anti-inflammatory effect, which puts TREG therapy at the forefront of future curative therapy of a wide range of autoimmune and neurodegenerative diseases, plus transplant complications, such as graft-versus-host disease (GVHD) and graft rejection. In addition, TREG therapy can provide a tissue regenerative effect, which places TREG cell therapy at the lead of novel regenerative medicine efforts to repair a myriad of tissue-based diseases, such as diseases of the skin, muscle, lung, liver, intestine, heart (myocardial infarction) and brain (stroke). RAPA-501-ALLO off-the-shelf cell therapy offers this potential dual threat mechanism of action that incorporates both anti-inflammatory and tissue repair effects for effective treatment of COVID-19 and multiple lethal conditions. RAPA-501-ALLO cells are generated from healthy volunteers, cryopreserved, banked, and are then available for off-the-shelf therapy anytime. During manufacturing, T cells are "reprogrammed" ex vivo using a novel, patented 7-day two-step process that involves T cell de-differentiation and subsequent re-differentiation towards the two key anti-inflammatory programs, the TREG and Th2 pathways, thus creating a "hybrid" product. The hybrid phenotype inhibits inflammatory pathways operational in COVID-19, including modulation of multiple cytokines and chemokines, which attract inflammatory cells into tissue for initiation of multi-organ damage. The hybrid TREG and Th2 phenotype of RAPA-501-ALLO cells cross-regulates Th1 and Th17 populations that initiate hyperinflammation of COVID-19. RAPA-501 immune modulation occurs in a T cell receptor independent manner, thus permitting off-the-shelf cell therapy. Finally, in experimental models of viral pneumonia and ARDS, TREG cells mediate a protective effect on the lung alveolar tissue. Because of this unique mechanism of action that involves both anti-inflammatory and tissue protective effects, the allogeneic RAPA-501 T cell product is particularly suited for evaluation in the setting of COVID-19-related ARDS.

COMPLETED
A Trial of Aclaris Therapeutics, Inc. (ATI)-450 in Patients With Moderate-severe Novel Coronavirus Disease 2019 (COVID-19)
Description

COVID-19 morbidity and mortality has been associated with Cytokine Release Syndrome (CRS) and Acute Respiratory Distress Syndrome (ARDS). ATI-450 is an oral small molecule MAPKAPK2 (MK2) inhibitor that potently inhibits multiple inflammatory cytokines. The investigator hypothesizes that MK2 pathway blockade during active COVID-19 infection in hospitalized participants will result in improvement in respiratory-failure free survival.

Conditions
COMPLETED
Assessment of N-95 Facemask for Use in COVID-19 Pandemic in Case of Shortage of Personal Protective Equipment
Description

The purpose of this study is to assess the safety and efficiency of an assembled modified mask in protecting health care workers against Coronavirus in case of any personal protective equipment shortage. At least 20 healthy participants will be recruited to try the modified mask. The modified masks will be made from masks that are already available as well as filters available in the pulmonary department at the Oklahoma City VA Health Care System

COMPLETED
Acalabrutinib Study With Best Supportive Care Versus Best Supportive Care in Subjects Hospitalized With COVID-19.
Description

CALAVI US will investigate the safety, efficacy and pharmacokinetics of acalabrutinib together with Best Supportive Care in the treatment of COVID-19.

Conditions
TERMINATED
A Study of LY3127804 in Participants With COVID-19
Description

A randomized, double-blind, placebo-controlled, clinical trial of LY3127804 in participants who are hospitalized with pneumonia and presumed or confirmed COVID-19.

SUSPENDED
Hydroxychloroquine in Patients With Newly Diagnosed COVID-19 Compared to Standard of Care
Description

This study will assess the efficacy of hydroxychloroquine in reducing the severity of symptoms in patients with COVID-19

COMPLETED
Safety and Immunogenicity Study of 2019-nCoV Vaccine (mRNA-1273) for Prophylaxis of SARS-CoV-2 Infection (COVID-19)
Description

This is a phase I, open-label, dose-ranging clinical trial in males and non-pregnant females, starting at 18 years of age, inclusive, who are in good health and meet all eligibility criteria. This clinical trial is designed to assess the safety, reactogenicity and immunogenicity of mRNA-1273 manufactured by ModernaTX, Inc. mRNA-1273 is a novel lipid nanoparticle (LNP)-encapsulated mRNA-based vaccine that encodes for a full-length, prefusion stabilized spike (S) protein of SARS-CoV-2. Enrollment will occur at up to 3 domestic clinical research sites. Up to one hundred and fifty-five subjects will be enrolled into one of thirteen cohorts (10 micrograms \[mcg\], 25 mcg, 50 mcg, 100 mcg, and 250 mcg). Subjects will receive an intramuscular (IM) injection (0.5 milliliters \[mL\]) of mRNA-1273 on Days 1 and 29 in the deltoid muscle and will be followed through 12 months post second vaccination (Day 394). Follow-up visits will occur 1, 2, and 4 weeks post each vaccination (Days 8, 15, 29, 36, 43, and 57), as well as 3, 6, and 12 months post second vaccination (Days 119, 209, and 394). The primary objective is to evaluate the safety and reactogenicity of a 2-dose vaccination schedule of mRNA-1273, given 28 days apart, across 5 dosages in healthy adults. Optional Substudy: This is an optional third mRNA-1273 vaccination substudy, in subjects 18 years of age and older, who received both the first and second mRNA-1273 vaccinations in the main study and meet all other substudy eligibility criteria. This optional third mRNA-1273 vaccination substudy is designed to assess safety, reactogenicity, and immunogenicity through 12 months post third vaccination (Day 731). Subjects who receive the third mRNA-1273 vaccination will exit the Schedule of Activities for the main study and will enter the Schedule of Activities for the optional substudy. Up to one hundred and twenty subject will be enrolled into two cohorts (consisting of participating subjects who received 2 doses of 25 or 50 mcg and participating subjects who received 2 doses of 100 and 250 mcg). Subjects will receive an IM injection (0.5 mL) at a dosage of 100 mcg/0.5 mL. The primary objective is to evaluate the safety and reactogenicity of a third mRNA-1273 vaccination, at a dosage of 100 mcg.

COMPLETED
Coronavirus Disease of 2019 (COVID-19) Health Education Initiative for School Safety
Description

The purpose of this study is to compare COVID-19 knowledge, experiences, and health behaviors between participants who received the health initiative and those who did not.

Conditions
ACTIVE_NOT_RECRUITING
A Study to Learn About How Well Yearly Updates to the COVID-19 Vaccine Work to Protect People From COVID-19 and How Much Money People Spend on Healthcare for COVID-19
Description

The purpose of this study is to learn about how well the yearly updates to the COVID-19 vaccine work in adults (age 18 years and above) with a healthy immune system (the body's cells, tissues and organs that work together to protect your body) and in children (age 6 months to 17 years). This study will use a collection of insurance claims and state vaccine registry data called HealthVerity. All patient names and other identifying information is removed. This study will include children who: * Are 6 months of age to 17 years of age * Are enrolled for at least 6 months in a row in a health insurance plan that provides data to HealthVerity * Are enrolled for at least 6 months in a row in a prescription drug insurance plan that provides data to HealthVerity * Live in the same US state for 6 months in a row * Live in a US state that requires COVID-19 vaccine reporting and provides all vaccine history data to HealthVerity * Do not have mismatches in sex and/or year of birth between any of the available datasets * Do not have records of having had COVID-19 and/or any COVID-19 vaccine in the 90 days before the start of the study This study will include adults who: * Are 18 years of age and older * Are enrolled for at least 12 months in a row in a health insurance plan that provides data to HealthVerity * Are enrolled for at least 12 months in a row in a prescription drug insurance plan that provides data to HealthVerity * Have lived in the same US state for at least 12 months * Live in a US state that requires COVID-19 reporting and provides all vaccine history data to HealthVerity * Do not have mismatches in sex and/or year of birth between any of the available datasets * Do not have records of having had COVID-19 and/or any COVID-19 vaccine in the 90 days before the start of the study This study will use the data that has already been collected, and no treatment or vaccine will be given in the study. People who match the information above will be followed in the HealthVerity database for up to 6 months following the first day that a new COVID-19 vaccine is available. This information will be reviewed to see if any of the following happen: * they had a COVID-19 vaccine * they're diagnosed with COVID-19 in a doctor's office * they visit the emergency department for COVID-19 * they visit urgent care for COVID-19 * they are hospitalized for COVID-19 The experiences of people who received a COVID-19 vaccine will be compared to the experiences of people who did not receive the vaccine. This will help to understand how well the Pfizer-BioNTech COVID-19 vaccine works at stopping COVID-19.

RECRUITING
A Study to Learn About How the Flu and COVID-19 Vaccines Act in Healthy People
Description

The purpose of this study is to learn about how the flu and COVID vaccines act when given alone or when mixed together. This study is seeking healthy participants aged 18 or older. All participants in this study will receive only 1 shot to their arm, either a flu or COVID vaccine, alone or mixed. Participants will take part in this study for about 6 months, and participants will need to visit the clinical study site at least 4 times.

RECRUITING
A Clinical Study of Molnupiravir to Prevent Severe Illness From Coronavirus Disease 2019 (COVID-19) in People Who Are High Risk (MK-4482-023)
Description

Researchers are looking for other ways to prevent severe illness from COVID-19. COVID-19 is a virus that most often causes mild flu or cold-like symptoms. However, people with certain health conditions or other factors have a high risk (chance) of getting severely ill from COVID-19, which can require a hospital stay or lead to death. Some people who are high risk for severe illness may be unable to take certain treatments for COVID-19 because they are not available to them, or they take other medicines that may react with a treatment and cause an unwanted effect. Molnupiravir (MK-4482) is a study medicine designed to stop the COVID-19 virus from copying itself in the body (multiplying). The goal of this study is to learn if molnupiravir prevents severe illness from COVID-19 more than placebo in people who are high risk.

COMPLETED
A Safety and Immune Response Study to Evaluate Varying Doses of an mRNA Vaccine Against Coronavirus Disease 2019 (COVID-19) in Healthy Adults
Description

The purpose of this study is to evaluate the safety, reactogenicity and immune responses of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA-CR-04 vaccine construct when administered in healthy adults previously vaccinated with SARS-CoV-2 mRNA vaccines.

Conditions
ACTIVE_NOT_RECRUITING
A Randomized, Double-Blind, Placebo-Controlled Phase 2/3 Study to Determine the Safety and Effectiveness of Azeliragon in the Treatment of Patients Hospitalized for Coronavirus Disease 2019 (COVID-19) or Pneumonia
Description

A new drug called azeliragon could be used to treat patients with COVID-19 or other pneumonia infections but the researchers don't know. In this study, they are learning the effects of azeliragon patients hospitalized for COVID-19 or pneumonia.

Conditions
COMPLETED
Digital Applications to Monitor Novel Coronavirus Disease and Response in Colombia - Syndromic and Vaccination Surveillance
Description

Brief Summary: The main objective of this activity is to assess the effectiveness of different messaging strategies (factual, narrative, mixed and a control) to promote COVID-19 adult vaccination.

WITHDRAWN
Understanding COVID-19 Vaccine Immunity in Tissue and Blood
Description

The purpose of this study is to understand the effects of COVID-19 vaccines on the immune system and how the COVID-19 vaccines provide protection and induce long term memory. Adults who are receiving a COVID-19 vaccine will be invited to participate in this study.

COMPLETED
An Observational Study, Called ROCURS, to Learn About COVID-19 Related Outcomes in People With Cancer Who Are Treated With Tyrosine Kinase Inhibitors (TKIs) Including Regorafenib or Sorafenib
Description

This is an observational study in which data from people with cancer who had the Coronavirus disease 2019 (COVID-19) are collected and studied. In observational studies, only observations are made without specified advice or interventions. The most recently discovered coronavirus (SARS-CoV-2) may cause illness in humans ranging from the common cold to serious illness, also known as COVID-19. People with cancer are particularly at risk of becoming very sick with COVID-19, especially during or shortly after a cancer treatment. Several treatments for COVID-19 have been tested in clinical studies. However, people with cancer or with recent cancer treatments were usually excluded. Tyrosine kinase inhibitors (TKIs) are used to treat several cancer types. TKIs including regorafenib and sorafenib block certain proteins, which are involved in the growth of cancer. They also have an anti-inflammatory effect and may be able to block the entry of the coronavirus into the cell. This could possibly prevent infection. However, data on COVID-19 from people with cancer receiving TKIs are missing. The main purpose of this study is to find out whether COVID-19 outcomes were different in people with cancer receiving TKIs compared to those receiving other anti-cancer drugs. To do this, researchers will compare COVID-19 outcomes within 30 days of COVID-19 diagnosis between both groups. The data for the comparison will come from databases called Optum and MarketScan. Besides this data collection, no further tests or examinations are planned in this study. There are no required visits or tests in this study. Data will be from October 2019 to June 2021 or the latest available data.

COMPLETED
A Study to Learn About a Repeat 5-Day Treatment With the Study Medicines (Called Nirmatrelvir/Ritonavir) in People 12 Years Old or Older With Return of COVID-19 Symptoms and SARS-CoV-2 Positivity After Finishing Treatment With Nirmatrelvir/Ritonavir
Description

The purpose of this study is to learn about the safety and effects of nirmatrelvir/ritonavir for the potential treatment of COVID-19 rebound. The study is seeking participants who: * Have completed treatment with nirmatrelvir/ritonavir * Have a rebound in COVID-19 symptoms * Are SARS-CoV-2 (COVID-19) positive All study medications will be taken 2 times a day by mouth for 5 days. The first dose of study medication is taken at the study clinic and the rest at home. We will examine the experiences of people receiving the study medicines to those who do not. This will help us determine if the study medicines are safe and effective. People taking part will be in this study for about 24 weeks. Enrolled participants will need to visit the study clinic at least 8 times during the study.

Conditions
WITHDRAWN
A Study to Learn About the Medicine Called Nirmatrelvir Used in Combination With Ritonavir in People With Weakened Immune Systems or at Increased Risk for Poor Outcomes Who Are Hospitalized Due to Severe COVID-19
Description

A Study to Learn About the Medicine Called Nirmatrelvir Used in Combination With Ritonavir in People with Weakened Immune Systems or at Increased Risk for Poor Outcomes who are Hospitalized Due to Severe COVID-19

COMPLETED
Safety and Effects of an Investigational COVID-19 Vaccine as Booster in Healthy People
Description

This is an exploratory Phase I, randomized, observer-blind, active-controlled, dose-escalation trial to evaluate four dose levels (DLs) of BNT162b4 given in combination with BNT162b2 Bivalent (original/Omicron BA.4/BA.5) to select a safe and tolerable dose and to evaluate BNT162b4 + BNT162b2 Bivalent (original/Omicron BA.4/BA.5) when given as Dose 1 and Dose 2 (booster) in Cohorts 1 and 2 and BNT162b4 + BNT162b2 Monovalent (OMI XBB.1.5) when given as Dose 2 (booster) in Cohorts 3a, 3b, 4a, and 4b, and 30 μg BNT162b4 when given alone as Dose 1 and Dose 2 in Cohort 5. The trial will use a staggered dosing process schema, i.e., enrollment into the next higher dose level is done sequentially and subject to safety data from the previous dose levels, with sentinel participants in Cohorts 1, 2, 3a, and 4a. Cohort 3b investigating the same dose level as cohort 3a but in participants aged \>55 years will be opened after safety data for participants aged 18-55 years in Cohort 3a has been reviewed. Enrollment into Cohorts 4a and 4b will be opened after safety data for Cohort 3a and 3b has been reviewed. Cohort 5 participants will not be randomized and will receive two doses of BNT162b4 alone after which a safety review will be performed after all participants have received Dose 2 in this cohort. BNT162b4 plus BNT162b2 Bivalent (original/Omicron BA.4/BA.5)/Monovalent (OMI XBB.1.5) will be co-administered (as a single injection). BNT162b4 alone will be administered as a single injection.

TERMINATED
A Study to Measure the Amount of Study Medicine in Blood in Adult Participants With COVID-19 and Severe Kidney Disease
Description

The purpose of this study is to learn about the side effects (safety) of the study medicine PF-07321332 (nirmatrelvir)/ritonavir for the treatment of mild to moderate COVID-19 infection in adults with severe renal impairment. The study will also look at the amounts of study drug in your blood. There will be 24 participants in this study; 12 of them will have severe renal impairment and not be on hemodialysis and 12 of them will be on hemodialysis. All participants in this study will take PF-07321332 (nirmatrelvir)/ritonavir by mouth for 5 days. During this time, they will have to collect blood samples to measure the study drug levels in their blood. After taking the study drug for 5 days, the participants will have follow-up visits for about another 28 days for a total of about 34 days in the study. The study team will check how each participant is doing during regular visits at the study clinic.

Conditions
COMPLETED
A Study to Learn About the Study Medicines (Nirmatrelvir Plus Ritonavir) in People Aged 12 Years or Older With COVID-19 and a Compromised Immune System
Description

The purpose of this clinical trial is to learn about the safety and effects of the study medicine (called Nirmatrelvir/Ritonavir) for the possible treatment of COVID-19. Patients with COVID-19 who have more difficulty in fighting against infections have a higher chance of severe illness. Such patients may benefit from longer treatment durations compared to the standard treatment regimen. The study is seeking participants who: * Have a confirmed COVID-19 infection * Are Immunocompromised * Experience onset of signs/symptoms attributable to the current COVID-19 infection within 5 days prior to screening and ≥1 signs/symptoms attributable to COVID-19 present on the day of randomization. In addition, this study will also evaluate the efficacy and safety of a second treatment course of nirmatrelvir/ritonavir in people who experience that their COVID-19 is flaring up within 14 days of having taken a 5-day treatment course of nirmatrelvir/ritonavir. For this group, the study is seeking participants who: * Have a confirmed COVID-19 infection * Experience a worsening of signs/symptoms after completing an initial 5-day course of nirmatrelvir/ritonavir * The worsening of COVID-19 symptoms must occur within 14 days after completion of the initial 5-day course of nirmatrelvir/ritonavir * Are Immunocompromised * Experience onset of signs/symptoms attributable to the current COVID-19 infection within 48 hours prior to screening and ≥1 signs/symptoms attributable to COVID-19 present on the day of randomization. All participants will be taking the study medicine for either 5, 10, or 15 days. The study medication will be taken by mouth 2 times a day. Participants will take part in this study for about 24 weeks. The first dose of study medication is taken at the study site and the rest at home. Selected participants will need to visit the study site at least 10 times during the study.

Conditions