📄 What This Document Is

This is an 8-K filing with an attached press release (Exhibit 99.1). Companies use 8-Ks to announce major news to investors. Today's news from Invivyd is all about big progress and a brand-new weapon in their fight against viruses.

👉 In simple terms: Invivyd is reporting strong data from its late-stage COVID-19 antibody trial and is launching a new project to create a groundbreaking treatment for measles.

🏢 What The Company Does

In simple terms... Invivyd is a biotech company that engineers powerful, lab-made antibodies. Think of them as precision-guided medicines that can immediately block a virus, unlike vaccines which take time to train your immune system. They are focused on serious respiratory viruses, starting with COVID-19 and now expanding to measles.

Their goal is to build a platform that can quickly create new antibodies for different viruses, making them a multi-virus powerhouse.

🚀 Key Moves & Clinical Progress

1. COVID-19 Program (VYD2311) is Accelerating

Invivyd's main COVID project is VYD2311, a next-generation antibody to prevent COVID-19. Its pivotal Phase 3 DECLARATION study just hit a major milestone.

• What Happened: The study uses a clever "re-estimation" rule. When 1,500 patients reached the halfway point (April 6th), they had already seen enough COVID cases to confirm strong statistical power. This triggered a pre-planned study upsizing.
• The Upsize: They are adding ~500 more participants to make the results even more robust. The total study size grows from 1,818 to about 2,300 people.
• Timeline Shift: Because of the larger study, top-line results will now likely come in Q3 2026, a modest delay from the previous "mid-year" (Q2/Q3) guidance.
• Regulatory Win: Invivyd and the FDA agreed on a plan (an "Initial Pediatric Study Plan") for a future study in kids aged 0-11. This is called the "DRUMMER" study and will only happen if the main DECLARATION trial succeeds.

👉 Why it matters: This isn't a setback. The upsizing shows the trial is working as designed and increases confidence in getting a clear, powerful result. The FDA alignment smooths the path for a future approval in children.

2. A New Star: The Measles Antibody (VMS063)

This is the big new announcement. Invivyd used its tech to invent VMS063, a potential first-in-class antibody for measles.

• The Problem: Measles is making a scary comeback in 2026 due to lower vaccination rates. There is no approved treatment, only supportive care. Vaccines are crucial but don't work for everyone (like infants or the immunocompromised).
• The Solution (VMS063): This antibody is designed to:
  • Treat active measles to shorten illness and prevent severe complications.
  • Prevent infection after exposure (post-exposure prophylaxis).
  • Protect vulnerable groups like infants before they can get vaccinated.
• Its Strengths: Early lab tests show it's extremely potent against all recent measles strains and is designed to last a long time in the body from a single dose.

👉 Why it matters: This targets a massive unmet medical need during a real public health crisis. It represents Invivyd's strategy to use its antibody "platform" to rapidly create new drugs for other dangerous viruses.

🔮 What's Next

Invivyd has a clear, packed roadmap:

1. Finish enrolling the bigger DECLARATION COVID trial and await results in Q3 2026.
2. Advance VMS063 through "IND-enabling" studies (the lab and animal work needed before human trials) with a goal of being ready for a first-in-human study by late 2026.
3. Plan the pediatric "DRUMMER" study for VYD2311, pending a successful main trial.
4. Hinted at more to come: They plan to announce discoveries for additional pathogens later in 2026.

⚖️ The Big Picture

👍 Strengths & Opportunities

• Powerful Platform: Their tech can rapidly generate best-in-class antibodies, as proven with both COVID and now measles.
• Near-Term Catalyst: The DECLARATION study result in Q3 2026 is a major event that could lead to a new COVID prevention option.
• Huge Unmet Need: Measles is a resurging threat with no specific treatment. VMS063 could be a game-changer for vulnerable populations.
• Regulatory Strategy: Aligning with the FDA on the pediatric plan early is savvy and de-risks the program.

⚠️ Risks & Challenges

• Clinical Trial Risk: The DECLARATION study must succeed. If it fails, the whole COVID program stalls.
• Regulatory Hurdles: Even with good data, the FDA must approve any product. The path for a new measles antibody is uncharted.
• Competitive & Market Landscape: It's unclear how a new COVID antibody would be used or reimbursed if updated vaccines remain available.
• Funding: Advanced clinical trials are extremely expensive. The company will need capital to execute its ambitious plans.

🧠 The Analogy

Invivyd is like a master locksmith for viruses. For COVID-19, they've already crafted a high-tech key (VYD2311) and are in the final stages of proving it works on the current lock (the virus). Now, using the same locksmithing tools, they've just announced they've designed a brilliant new key for a different, very dangerous lock (measles) that nobody has been able to pick before. Their platform lets them do this rapidly and effectively.

🧩 Final Takeaway

Invivyd is firing on two major cylinders: 1) Nearing the finish line on a pivotal late-stage study for a next-gen COVID antibody, with results expected this summer, and 2) Pivoting its powerful technology to attack a worsening measles outbreak with a potentially groundbreaking new treatment. The company is executing a clear strategy to become a multi-virus specialist.

Contacts: Media: (781) 208-0160, [email protected] | Investors: (781) 208-1747, [email protected]