Evaluating antiviral treatments to prevent long-term heart issues after COVID-19

Antiviral Strategies in the Prevention of Long-term Cardiovascular Outcomes Following COVID-19: The paxloviD/Remdesivir Effectiveness For the prEvention of loNg coviD (DEFEND) Clinical Trial

Phase 4 Interventional Mount Sinai Hospital, Canada · NCT06792214

This study is testing whether antiviral treatments like Paxlovid and Remdesivir can help prevent heart problems in adults who are hospitalized with COVID-19.

Quick facts

PhasePhase 4
Study typeInterventional
Enrollment118 (estimated)
Ages18 Years and up
SexAll
SponsorMount Sinai Hospital, Canada Academic / other
Locations4 sites (Kingston, Ontario and 3 other locations)
Trial IDNCT06792214 on ClinicalTrials.gov

What this trial studies

The DEFEND trial aims to assess the effectiveness of Paxlovid and Remdesivir in preventing cardiovascular complications in hospitalized adults who test positive for SARS-CoV-2. This pilot study will help determine the feasibility of a larger multicenter trial by estimating recruitment rates and validating hospital-based outcome measures. Participants aged 18 and older will be enrolled from four hospitals in Ontario, and the study will follow a double-blind, randomized, placebo-controlled design. The trial will also track the occurrence of serious cardiovascular events within one year following treatment.

Who should consider this trial

Good fit: Ideal candidates are hospitalized adults aged 18 and older with a positive PCR test for SARS-CoV-2.

Not a fit: Patients with severe allergies to the study medications or those requiring supplemental oxygen will not benefit from this study.

Why it matters

Potential benefit: If successful, this study could significantly reduce the risk of long-term cardiovascular issues in COVID-19 survivors.

How similar studies have performed: This approach is novel, as it is the first clinical trial specifically targeting cardiovascular outcomes following COVID-19.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* ≥18 years old
* Positive PCR test for SARS-CoV-2 within 5 days of admission to hospital
* Normoxic (not receiving supplemental oxygen)
* Able to provide informed written consent (or, if patient is unable, have substitute decision maker available)

Exclusion Criteria:

* Absolute contraindications to Paxlovid or Veklury (any of the following): Severe allergy to Paxlovid or Veklury (e.g. anaphylaxis), co-administration with drugs highly dependent on CYP3A for clearance, co-administration with potent CYP3A inducers
* Exposure to Paxlovid or Veklury within previous 14 days;
* Receiving supplemental oxygen;
* Known positive SARS-CoV-2 PCR or rapid antigen test 5-90 days prior to admission;
* Limited life expectancy estimated to be ≤3 months;
* Pregnant and breastfeeding women

Where this trial is running

Kingston, Ontario and 3 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions SARS CoV-2 Post-Acute SequelaeSARS CoV-2long covid
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.