Oral Nirmatrelvir–Ritonavir for Covid-19 in Higher-Risk Outpatients
et al., New England Journal of Medicine, doi:10.1056/NEJMoa2502457 (results released 9/10/2025), CanTreatCOVID, NCT05614349, Sep 2025
Results for the CanTreatCOVID trial. See Butler et al. for details.
Standard of Care (SOC) for COVID-19 in the study country,
the United Kingdom, is very poor with very low average efficacy for approved treatments2.
The United Kingdom focused on expensive high-profit treatments, approving only one low-cost early treatment, which required a prescription and had limited adoption. The high-cost prescription treatment strategy reduces the probability of early treatment due to access and cost barriers, and eliminates complementary and synergistic benefits seen with many low-cost treatments.
|
risk of death/hospitalization, 51.7% lower, RR 0.48, p = 0.39, treatment 2 of 343 (0.6%), control 4 of 324 (1.2%), NNT 153, odds ratio converted to relative risk, day 28.
|
|
risk of no recovery, 42.2% lower, RR 0.58, p < 0.001, treatment 73 of 345 (21.2%), control 112 of 306 (36.6%), NNT 6.5, day 14.
|
|
risk of no recovery, 34.4% lower, RR 0.66, p < 0.001, treatment 86 of 277 (31.0%), control 115 of 245 (46.9%), NNT 6.3, inverted to make RR<1 favor treatment, odds ratio converted to relative risk, no early sustained recovery.
|
|
recovery time, 33.3% lower, relative time 0.67, treatment 343, control 324.
|
| Effect extraction follows pre-specified rules prioritizing more serious outcomes. Submit updates |
Butler et al., 10 Sep 2025, Randomized Controlled Trial, United Kingdom, peer-reviewed, 42 authors, study period 8 December, 2021 - 30 September, 2024, trial NCT05614349 (history) (CanTreatCOVID).
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