Invivyd starts FLINTLOCK study: what it means for Invivyd stock

Invivyd (US00534A1025) started the FLINTLOCK Phase 2 study on October 14, 2026, testing VYD2311 in adults with Long COVID or Post-Vaccination Syndrome, according to Invivyd. The trial plans enrollment of 130 participants and initial data are expected in mid-2027.

What the trial means

FLINTLOCK will test a high-dose version of VYD2311 in a randomized, double-blind, placebo-controlled design. Participants will receive an intravenous loading dose followed by intramuscular injections on days 30 and 60, with clinical evaluations continuing through day 90.

The program broadens the role of VYD2311 beyond prevention. Invivyd said the study will assess safety, tolerability, pharmacokinetics and clinical efficacy in adults aged 18 to 65 with at least two persistent symptoms after infection or vaccination. PEMGARDA is not authorized for treating Long COVID or Post-Vaccination Syndrome.

Invivyd's recent milestones

Invivyd reported positive LIBERTY Phase 3 topline data on September 29, 2026. The study enrolled 210 healthy adults, and treatment-emergent adverse events, injection-site reactions or hypersensitivity affected 56.5 percent of VYD2311 recipients versus 91.4 percent of those receiving an mRNA vaccine, according to Invivyd.

On October 5, 2026, Invivyd announced inducement grants covering 157,500 options for six new employees. The October 14 FLINTLOCK announcement then added a second clinical indication for VYD2311, making the trial design and the timing of initial data the key near-term milestones.

Revenue and reporting dates

In the second quarter of 2026, PEMGARDA net product revenue rose 21 percent year over year to USD 14.3 million from USD 11.8 million. Quarterly net loss widened to USD 44.4 million from USD 14.7 million, according to PRISM MarketView.

TradingView lists November 5, 2026, as the next earnings date. The FLINTLOCK release dated October 14, 2026, points to mid-2027 for initial study data.

Stock valuation in dollars

On October 15, 2026, Nasdaq-listed IVVD was last at USD 0.67 at 4:00 p.m. ET. The finance snapshot put Invivyd's market capitalization at USD 197.1 million on the same date, while the 52-week range stood at USD 0.53 to USD 3.07.

For investors, the clinical timetable now sits beside a commercial comparison: second-quarter revenue reached USD 14.3 million, while the quarterly net loss was USD 44.4 million. The next disclosed checkpoint is the November 5 reporting date, followed by the mid-2027 FLINTLOCK data target.

Market values and clinical milestones point to a company balancing commercial revenue with costly development work. The trial's 130-participant design gives the next program update a defined scale.