Post-exposure Lopinavir-Ritonavir Prophylaxis versus Surveillance for Individuals Exposed to SARS-CoV-2: The COPEP Pragmatic Open-Label, Cluster Randomized Trial

Abstract

Background: Since the beginning of the COVID-19 pandemic, no direct antiviral treatment is effective as post-exposure prophylaxis (PEP). Lopinavir/ritonavir (LPV/r) was repurposed as a potential PEP agent against COVID-19.

Methods: We conducted a pragmatic open-label, parallel, cluster-randomised superiority trial in four sites in Switzerland and Brazil between March 2020 to March 2021. Clusters were randomised to receive LPV/r PEP (400/100 mg) twice daily for 5 days or no PEP (surveillance). Exposure to SARS-CoV-2 was defined as a close contact of >15 minutes in <2 metres distance or having shared a closed space for ≥2 hours with a person with confirmed SARS-CoV-2 infection. The primary outcome is the occurrence of COVID-19 defined by a SARS-CoV-2 infection (positive oropharyngeal SARS-CoV-2 PCR and/or a seroconversion) and ≥1 compatible symptom within 21 days post-enrolment. ClinicalTrials.gov (Identifier: NCT04364022); Swiss National Clinical Trial Portal: SNCTP 000003732.

Findings: Of 318 participants, 157 (49.4%) were women; median age was 39 (interquartile range, 28-50) years. A total of 209 (179 clusters) participants were randomised to LPV/r PEP and 109 (95 clusters) to surveillance. Baseline characteristics were similar, with the exception of baseline SARS-CoV-2 PCR positivity, which was 3-fold more frequent in the LPV/r arm (34/209 [16.3%] vs 6/109 [5.5%], respectively). During 21-day follow-up, 48/318 (15.1%) participants developed COVID-19: 35/209 (16.7%) in the LPV/r group and 13/109 (11.9%) in the surveillance group (unadjusted hazard ratio 1.44; 95% CI, 0.76-2.73). In the primary endpoint analysis, which was adjuted for baseline imbalance, the hazard ratio for developing COVID-19 in the LPV/r group vs surveillance was 0.60 (95% CI, 0.29-1.26; p =0.18).

Interpretation: The role of LPV/r as PEP for COVID-19 remains unanswered. Although LPV/r over 5 days did not significantly reduce the incidence of COVID-19 in exposed individuals, we observed a change in the directionality of the effect in favour of LPV/r after adjusting for baseline imbalance. LPV/r for this indication merits further testing against SARS-CoV-2 in clinical trials.

Funding: Swiss National Science Foundation (project no.: 33IC30_166819) and the Private Foundation of Geneva University Hospitals (Edmond Rothschild (Suisse) SA, Union Bancaire Privée and the Fondation pour la recherche et le traitement médical).

Conflict of interest statement

Dr. Niklaus D Labhardt reports support for attending CROI conference 2020 and AIDS conference 2020 by Gilead Sciences, support for attending CROI Conference 2021 by ViiV healthcare, and participation on a Data Safety Monitoring Board for the C1 6201 PROTECT trial by Pharming Group NV. Dr. Mikaela Smit reports scientific grants at Imperial College London by CDRF (prime is PEPFAR) and NIH, and consulting fees for modeling consulting by Gilead Sciences, IAS, Maple Health. Dr. Enos Bernasconi reports grants from Merck & Co. and Swiss National Science Foundation, consulting fees and support for attending meeting by Gilead Sciences, Merck & Co., ViiV healthcare, Pfizer AG, Abbvie, paid to the Lugano Regional Hospital. Dr. Alexandra Calmy reports grant from MSD for qualitative research on women and clinical trials, and unrestricted grant from Gilead, ViiV Healthcare, MSD and SIDAIDE foundation related to the funding support to LIPO and metabolims Day Hospital at Geneva University Hospitals. All other authors have nothing to disclose.

© 2021 The Author(s).

Figures

Figure 1

Flow Diagram of Participants in the COPEP Trial