No primary day-90 benefit was established for nirmatrelvir-ritonavir
For established Long COVID, neither the 15-day nor 25-day regimen established a benefit versus placebo on primary patient-reported autonomic, cognitive, or exercise outcomes.
The USA trial was randomized, double-blind, and placebo-controlled. Across all 963 participants, 42 (4%) experienced 52 serious adverse events, and there were no deaths; events were not reported as a between-group comparison.
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Adjusted difference versus placebo in the day-90 autonomic-phenotype primary patient-reported outcome with the 15-day nirmatrelvir-ritonavir regimen
-0.1% (p=0.99)
95% CI: -12.5 to 12.3
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added
Adjusted difference versus placebo in the day-90 cognitive-phenotype primary patient-reported outcome with the 25-day nirmatrelvir-ritonavir regimen
3.2% (p=0.65)
95% CI: -10.4 to 16.8
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added
Adjusted difference versus placebo in the day-90 cognitive-phenotype primary patient-reported outcome with the 15-day nirmatrelvir-ritonavir regimen
-2.2% (p=0.74)
95% CI: -15.5 to 11.1
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added
Adjusted difference versus placebo in the day-90 exercise-phenotype primary patient-reported outcome with the 25-day nirmatrelvir-ritonavir regimen
-7.8% (p=0.19)
95% CI: -19.5 to 3.8
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added
Adjusted difference versus placebo in the day-90 autonomic-phenotype primary patient-reported outcome with the 25-day nirmatrelvir-ritonavir regimen
-6.4% (p=0.30)
95% CI: -18.5 to 5.7
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added
Adjusted difference versus placebo in the day-90 exercise-phenotype primary patient-reported outcome with the 15-day nirmatrelvir-ritonavir regimen
0.9% (p=0.88)
95% CI: -11.4 to 13.2
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added
Serious adverse events across all study participants over the course of the trial; this was not reported as a between-group comparison
42 of 963 participants (4%; 52 serious adverse events), with no deaths
Baden, Lindsey R et al.. Nirmatrelvir-ritonavir targeting viral persistence in post-COVID-19 condition (long COVID) in the USA (RECOVER-VITAL): a randomised, double-blind, placebo-controlled, phase 2 trial.. The Lancet. Infectious diseases. 2026.
Added