# Invivyd Begins Phase 2 FLINTLOCK Trial of VYD2311 for Long COVID

- URL: https://stocks.freetheai.org/news/invivyd-begins-phase-2-flintlock-trial-of-vyd2311-for-long-covid-adab5b
- Published: 2026-10-14T11:01:00Z
- Category: company_news; sentiment: mixed; impact: medium
- Symbols: [NASDAQ:IVVD](https://stocks.freetheai.org/symbols/NASDAQ-IVVD)
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Invivyd, Inc. (IVVD) and the SPEAR Study Group have started the FLINTLOCK Phase 2 clinical trial evaluating VYD2311, an investigational monoclonal antibody for individuals suffering from Long COVID or Post-Vaccination Syndrome. The proof-of-concept study aims to enroll approximately 130 adults between ages 18 and 65 who experience two or more persistent symptoms.

Long COVID remains a widespread chronic condition with limited treatment options. VYD2311 is designed to target the SARS-CoV-2 spike protein and neutralize circulating viral variants. Participants in the study will receive an initial high-dose intravenous infusion followed by monthly intramuscular injections at 30 and 60 days, with clinical efficacy and safety monitored through Day 90.

Invivyd expects initial data from the FLINTLOCK trial in mid-2027. The company is also evaluating VYD2311 in other clinical studies, including the Phase 3 DECLARATION trial for COVID-19 prevention, while its stock traded at $0.646 per share following the announcement.

## Key points

- Invivyd launched the Phase 2 FLINTLOCK clinical trial for its investigational monoclonal antibody VYD2311.
- The study targets adults aged 18 to 65 suffering from Long COVID or Post-Vaccination Syndrome.
- The trial will enroll roughly 130 participants and assess treatment safety and efficacy through Day 90.
- Initial data from the Phase 2 proof-of-concept study is anticipated in mid-2027.

## Questions and answers

### What is the FLINTLOCK trial testing?

The Phase 2 FLINTLOCK trial evaluates the safety, tolerability, and efficacy of Invivyd's monoclonal antibody VYD2311 in adults with Long COVID or Post-Vaccination Syndrome.

### When will Invivyd report results from the FLINTLOCK study?

Invivyd expects to report initial data from the FLINTLOCK trial in mid-2027.

### How is VYD2311 administered in the trial?

Participants receive an initial intravenous infusion on Day 1 followed by monthly intramuscular injections on Day 30 and Day 60.