LifestyleExercise

Nirmatrelvir-ritonavir for 15 or 25 days does not improve long COVID symptoms in cognitive, autonomic, or exercise phenotypes

In a randomized, double-blind, placebo-controlled phase 2 trial, 959 adults with long COVID were assigned to 15 or 25 days of nirmatrelvir-ritonavir or placebo. No statistically significant benefits were observed for any primary endpoint across the three symptom phenotypes (cognitive, autonomic, exercise). Adjusted differences for primary outcomes were small and non-significant, with p-values ranging from 0.19 to 0.99.

Last updated: Sep 2, 2026•1 RCTs•📖 Read as article →

Evidence Score

Evidence Score48/100
Human RCT★★☆☆☆
Meta-analysis☆☆☆☆☆
Mechanism★★★★★
Safety★★★★☆
Confidencelow

Study Evidence

Study 1. 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.

observational

Baden LR, Shah NS, Liu STH, Cohen J, Moy J, Kumar A, McComsey GA, Chen P, Floris-Moore M, Singer NG, Fernandez I, Slandzicki AJ, Wiley Z, Kadl A, Kaminsky DA, Hsu H, Walker TA, Hope AA, Ostrosky-Zeichner L, Goldman JD, Peluso MJ, Patterson TF, Parthasarathy S, Mullington JM, Bolin P, Jolley SE, Krishnan JA, Castro M, Hodder SL, Pemu P, Chu HY, Risbano MG, Jerath MR, Mylonakis E, Hurt RT, Alicic R, Azad NS, Sala MA, Harkins MS, Parsonnet J, Stafford N, Robinson P, Hussain S, Qiao X, Hawk ST, Lillestol M, Erdmann N, Gebo KA, Sudhindra P, Sassine J, Marshall GD, Chatterjee T, Morse CG, Kedar E, Stringer WW, Frontera JA, Jordan M, Blaskewicz C, Santana JL, Foot RA, Wongtrakool C, McCarthy MW, Mehari A, Amon A, Cohen AK, Jain N, Maughan C, Lindsay D, Olson R, Broderick S, Rowe P, O'Brien SM, Walt DR, Levy BD, Jason LA, Low PA, Shibao CA, Make B, Bateman L, Redline S, Knopman D, Hernandez AF, Nolen TL, Reist C, Berdan L, Whitley R, Zimmerman KO · The Lancet. Infectious diseases (2026)

Participants: N/A
Duration: 90 days (follow-up)
Intervention: Nirmatrelvir-ritonavir (300 mg nirmatrelvir-100 mg ritonavir twice daily) for 15 days or 25 days, compared to placebo
Outcome: Patient-reported outcomes at day 90: PROMIS Cognitive Function Short Form 8a, Orthostatic Hypotension Questionnaire question 1, and modified DePaul Symptom Questionnaire Post-Exertional Malaise short form; secondary phenotype-specific performance measures
Effect Size: Adjusted differences for primary endpoints ranged from -7.8% to 3.2%, all non-significant (p>0.05)
Population: Adults (≥18 years) with persistent symptoms (≥12 weeks) after SARS-CoV-2 infection, with cognitive, autonomic, or exercise phenotypes (n=959 in modified intention-to-treat population)

Result:

PubMed: 42673984DOI: 10.1016/S1473-3099(26)00406-8

Mechanism Graph

Hypothesis: viral persistence contributes to long COVID symptoms
↓
Nirmatrelvir-ritonavir inhibits SARS-CoV-2 protease, reducing viral replication
↓
If viral persistence is a driver, antiviral treatment should reduce symptom burden
↓
Result: No significant improvement in symptoms, suggesting viral persistence may not be the sole cause or treatment duration/dose insufficient

Limitations

  • ⚠The trial was phase 2, not powered for definitive efficacy
  • ⚠Only three symptom phenotypes were included, limiting generalizability to other long COVID presentations
  • ⚠No measurement of viral persistence or clearance was reported in the abstract
  • ⚠The study was conducted in the USA, potentially limiting external validity

Frequently Asked Questions

Did nirmatrelvir-ritonavir improve long COVID symptoms?▼

No, the trial found no statistically significant benefit for any of the three symptom phenotypes (cognitive, autonomic, exercise) after 15 or 25 days of treatment.

What was the sample size and duration of this trial?▼

The trial enrolled 959 participants (modified intention-to-treat) and followed them for 90 days after treatment initiation.

What were the primary outcomes measured?▼

Primary outcomes were patient-reported measures of cognitive function, orthostatic hypotension symptoms, and post-exertional malaise, assessed at day 90.

Are there any safety concerns with nirmatrelvir-ritonavir in long COVID?▼

No safety signals were observed; there were no deaths, and serious adverse events occurred in 4% of participants, similar to placebo.

Products

Affiliate links coming soon. We only recommend products that match the doses and forms used in the cited research.

References

  1. 1.Baden LR, Shah NS, Liu STH, Cohen J, Moy J, Kumar A, McComsey GA, Chen P, Floris-Moore M, Singer NG, Fernandez I, Slandzicki AJ, Wiley Z, Kadl A, Kaminsky DA, Hsu H, Walker TA, Hope AA, Ostrosky-Zeichner L, Goldman JD, Peluso MJ, Patterson TF, Parthasarathy S, Mullington JM, Bolin P, Jolley SE, Krishnan JA, Castro M, Hodder SL, Pemu P, Chu HY, Risbano MG, Jerath MR, Mylonakis E, Hurt RT, Alicic R, Azad NS, Sala MA, Harkins MS, Parsonnet J, Stafford N, Robinson P, Hussain S, Qiao X, Hawk ST, Lillestol M, Erdmann N, Gebo KA, Sudhindra P, Sassine J, Marshall GD, Chatterjee T, Morse CG, Kedar E, Stringer WW, Frontera JA, Jordan M, Blaskewicz C, Santana JL, Foot RA, Wongtrakool C, McCarthy MW, Mehari A, Amon A, Cohen AK, Jain N, Maughan C, Lindsay D, Olson R, Broderick S, Rowe P, O'Brien SM, Walt DR, Levy BD, Jason LA, Low PA, Shibao CA, Make B, Bateman L, Redline S, Knopman D, Hernandez AF, Nolen TL, Reist C, Berdan L, Whitley R, Zimmerman KO. "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. PMID: 42673984 DOI: 10.1016/S1473-3099(26)00406-8
Disclaimer: This content is for educational purposes only and is not medical advice. Evidence scores reflect the quality and quantity of available research, not clinical recommendations. Always consult a healthcare professional before starting any supplement or intervention.