Evaluation of Protease Inhibition for COVID-19 in Standard-Risk Patients (EPIC-SR).

Summary

The primary hypothesis to be tested is whether or not there is a difference in time to sustained alleviation of all targeted COVID-19 signs and symptoms through Day 28 between PF-07321332/ritonavir and placebo.

Timeline

Start

2021-08-25

Primary completion

2022-07-25

Completion

2022-07-25

Outcome

Missed primary endpoint

Stopped (Enrollment): “Enrollment ceased due to a very low rate of hospitalization or death observed in the standard-risk patient population”

registry analysis (superiority test); Nirmatrelvir 300 mg + Ritonavir 100 mg vs Placebo; p = 0.6027; Log Rank NCT05011513 ↗

Publications

• Brown TM, Kanu C, Harrington M. Assessing participants' experiences with the COVID-19 symptom diary in a clinical trial. J Patient Rep Outcomes. 2025 Aug 11;9(1):99. doi: 10.1186/s41687-025-00901-5.
• Baniecki ML, Guan S, Rai DK, Yang Q, Lee JT, Hao L, Weinstein E, Hyde C, Cardin RD, Soares H, Hammond J. Integrated virologic analysis of resistance to nirmatrelvir/ritonavir in individuals across four phase 2/3 clinical studies for the treatment of COVID-19. EBioMedicine. 2025 Aug;118:105819. doi: 10.1016/j.ebiom.2025.105819. Epub 2025 Jun 30.
• Hammond J, Fountaine RJ, Yunis C, Fleishaker D, Almas M, Bao W, Wisemandle W, Baniecki ML, Hendrick VM, Kalfov V, Simon-Campos JA, Pypstra R, Rusnak JM. Nirmatrelvir for Vaccinated or Unvaccinated Adult Outpatients with Covid-19. N Engl J Med. 2024 Apr 4;390(13):1186-1195. doi: 10.1056/NEJMoa2309003.

Drugs

Evaluation	Drug	Modality	Dose	Route
Subject	Nirmatrelvir	Small molecule	300 mg	Oral
Subject	Ritonavir	Other / unclassified	100 mg	Oral

Indications