Key Highlights

  • Vir Biotechnology (NASDAQ:VIR) rose about 13% to USD 13.85 on November 9, 2026, above its prior 52-week high of USD 12.45, after positive Phase 3 results.
  • In the ECLIPSE 1 trial, 44% of patients on monthly elebsiran and tobevibart achieved undetectable virus with normal liver enzymes at week 48, against 0% in the delayed treatment group.
  • Undetectable hepatitis Delta virus was achieved in 79% of treated patients, including 85% of those with cirrhosis, and every treated patient had a virologic response.
  • The company plans to submit for US approval in mid-2027 after two further Phase 3 studies report in the first quarter of 2027.

What the Trial Showed

Hepatitis delta is the most severe form of viral hepatitis and can only infect people who also carry hepatitis B. It progresses quickly to cirrhosis and liver cancer, and treatment Options in the United States are very limited, leaving a clear unmet need. ECLIPSE 1, announced on November 8, 2026, randomised 124 patients two to one to monthly injections of elebsiran and tobevibart or to treatment delayed until week 12. At week 48, 44% of treated patients met the combined primary endpoint of undetectable virus and normal liver enzymes, against none in the comparison group. On the key secondary endpoint, 79% reached undetectable virus. All treated patients achieved a virologic response, liver enzymes normalised in 53% against 5% and hepatitis B surface antigen fell below 10 units in 95% of patients, a potentially important signal for longer-term control of the underlying hepatitis B infection.

Why the Market Responded

The strength and consistency of the data across endpoints reduced the main uncertainty around the programme of Vir Biotechnology (NASDAQ:VIR). Results in cirrhotic patients, the hardest group to treat, were as strong as in the overall population, with 85% achieving undetectable virus against 73% in those without cirrhosis. Safety was clean, with one grade 3 treatment-related event, a fall in neutrophil count that resolved within 15 days, no treatment interruptions or discontinuations and mainly flu-like symptoms after the first dose. Earlier Phase 2 data showed durable responses through 96 weeks. The combination already holds breakthrough therapy and fast track status in the United States and priority and orphan designations in Europe, which could shorten review timelines in both regions. The rally pushed the Market Value to about USD 2.09 billion.

Risks and Next Steps

Two further Phase 3 trials, ECLIPSE 2 and ECLIPSE 3, are due to report in the first quarter of 2027, and the company plans a US filing in mid-2027 using all three studies. Holders of Vir Biotechnology (NASDAQ:VIR) face several risks. The confirmatory trials could produce weaker results, regulators may focus on the composite endpoint rate of 44%, and the hepatitis delta market, while serious, is relatively small and concentrated outside the United States, where a partner holds rights in Europe and Australia. The company remains loss-making, although its third-quarter loss was narrower than expected, so funding needs could rise as it builds a commercial organisation. Investors will watch the remaining Phase 3 readouts, presentations of detailed ECLIPSE 1 data at medical meetings and plans for launch preparation, Manufacturing scale-up and pricing in 2027.

Where Things Stand

Vir rose about 13% to USD 13.85 on November 9, 2026 after ECLIPSE 1 showed 44% of treated hepatitis delta patients reaching the combined endpoint and 79% achieving undetectable virus, with clean safety. Two more Phase 3 trials report in early 2027 ahead of a planned mid-2027 US filing. Confirmatory data and commercial plans are the next tests.