This filing does not appear to be a standard SEC form (10-K, 10-Q, 8-K, or Form 4). It is a press release / news wire announcement from Biohaven Ltd. However, it was submitted as the filing content to analyze, so I will treat it as an 8-K equivalent press release disclosure and cover it accordingly, since it contains substantial substantive content well above 150 words.

Biohaven Ltd. (NYSE:BHVN) announced on November 5, 2026, continued progress in its Graves' disease program, including active enrollment in the pivotal Phase 3 trial of BHV-1300 and three scientific poster presentations at the 2026 American Thyroid Association Annual Meeting in Philadelphia, Pennsylvania.

Key Highlights

  • Phase 3 enrollment active: The randomized, double-blind, placebo-controlled trial of BHV-1300 is enrolling approximately 300 adults at more than 55 sites across the United States and Canada, with additional sites activating in Japan, UK, Australia, and EU.
  • Phase 1b results: Weekly subcutaneous BHV-1300 1000 mg produced mean reductions in anti-TSHR-IgG1 autoantibodies of approximately 80% by week 12, with free T4 normalizing at a median of 3 weeks and free T3 at a median of 5 weeks.
  • Ono Pharmaceutical collaboration: In October 2026, Ono Pharmaceutical licensed the MoDE pan IgG degrader portfolio for Japan, South Korea, Taiwan, and ASEAN; Biohaven received $80 million upfront and is eligible for a further $20 million on a milestone anticipated within a year, plus royalties of approximately twenty percent on net sales.
  • Patient burden data: In a 14-participant interview study, 93% of participants reported fatigue and 100% reported an emotional impact, with anxiety (64%), depression (57%), and effects on self-image (43%) among the most common.
  • Preclinical BHV-1440 data: The TRAP degrader BHV-1440 internalized anti-TSHR antibody M22 in primary human hepatocytes across three donors with an average EC50 of 0.73 nM, and a single subcutaneous dose reduced circulating M22 within two hours and returned elevated T4 to baseline by 24 hours in a mouse model.
  • No new Graves' therapy in over 70 years: According to the filing, no new therapy has been approved for Graves' disease in more than seventy years.

Biohaven's Pivotal BHV-1300 Trial and Ono Collaboration Detail the Program's Scope

According to the filing, BHV-1300 is built on Biohaven's MoDE extracellular protein degrader technology, exclusively licensed from Yale University, where it originated in the laboratory of David Spiegel, M.D., Ph.D. The molecule is described as a bifunctional small molecule: one end binds the target in circulation and the other engages the asialoglycoprotein receptor (ASGPR) on liver cells, directing the target to lysosomal degradation while ASGPR recycles to the cell surface. The filing states BHV-1300 degrades IgG1, IgG2, and IgG4 while sparing IgG3, which the filing notes mediates protection against bacteria, viruses, and parasites.

The Phase 3 study, the filing discloses, evaluates restoration of normal thyroid function at week 26 in the absence of an antithyroid drug. Additional sites are described as activating through the fourth quarter of 2026 and the first quarter of 2027. The filing also states that nearly 200 individuals have received MoDE and TRAP degraders in Phase 1 testing, with most adverse events described as mild and self-resolving. Biohaven retains all rights outside the Ono-licensed territory, including the United States, Europe, and China, and retains worldwide rights to its TRAP degraders, according to the filing.

On the patient-experience side, the filing reports findings from semi-structured interviews with 14 adults with Graves' disease. It discloses that 13 of 14 participants (93%) reported two or more simultaneous symptoms, 10 (71%) reported five or more, and one participant reported 11. Even among the 8 participants (57%) with well-controlled thyroid levels, all had symptoms and 6 described them as recurring or persistent. The filing quotes Michele Potashman, Ph.D., Head of Clinical Outcomes Assessments and Health Economics at Biohaven, as stating: "Biochemical control is not the same as feeling well."

What Was Disclosed

Biohaven disclosed Phase 3 enrollment status for BHV-1300 in Graves' disease, Phase 1b clinical results, the terms of the October 2026 Ono Pharmaceutical licensing agreement, patient burden interview findings, and preclinical data for the TRAP degrader BHV-1440, all presented in connection with the 2026 ATA Annual Meeting.