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

Pfizer

Status and phase: Completed; Phase 2

Conditions: COVID-19

Treatments: Drug: ritonavir; Drug: placebo for nirmatrelvir; Drug: nirmatrelvir

Study type: Interventional

Funder types: Industry

Identifiers

NCT05567952

C4671042

2022-002827-36 (EudraCT Number)

Details and patient eligibility

About

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.

Enrollment: 436 patients

Sex: All

Ages: 12+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Documentation of nirmatrelvir/ritonavir treatment with patient-reported 100% compliance. Symptom alleviation or resolution in COVID-19 signs/symptoms followed by a worsening (rebound) of signs/symptoms after completing an initial 5-day course of nirmatrelvir/ritonavir
• Onset of rebound in COVID-19 symptoms within 2 weeks (14 days) after the completion of the initial 5-day course of nirmatrelvir/ritonavir.
• Onset of rebound in signs/symptoms attributable to COVID-19 within 48 hours prior to randomization and ≥1 sign/symptom attributable to COVID-19 present on the day of randomization.
• SARS-CoV-2 infection as determined by rapid antigen testing within 24 hours prior to randomization
• At least 1 characteristic or underlying medical condition associated with an increased risk of developing severe illness from COVID-19.

Exclusion criteria

• Current need for hospitalization, hospitalized for the COVID-19 infection or anticipated need for hospitalization within 24 hours after randomization
• History of severe chronic liver disease
• Receiving dialysis or have known age-specific estimated glomerular filtration rate (eGFR) or estimated creatinine clearance (eCrCl) <30 mL/min/1.73 m2 at screening as measured by a serum creatinine point of care device
• Oxygen saturation of <92% on room air obtained at rest within 24 hours prior to randomization
• Immunocompromised.
• Current use of any prohibited concomitant medication(s)
• Females who are pregnant and <14 weeks gestation

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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436 participants in 2 patient groups

nirmatrelvir plus ritonavir for 5 days

Experimental group

Description:

Nirmatrelvir (2 tablets) plus ritonavir (1 capsule) will be given by mouth every 12 hours for 5 days

Treatment:

Drug: nirmatrelvir

Drug: ritonavir

placebo plus ritonavir for 5 days

Other group

Description:

placebo (2 tablets) plus ritonavir (1 capsule) will be given by mouth every 12 hours for 5 days

Treatment:

Drug: placebo for nirmatrelvir

Drug: ritonavir