IGM Biosciences (IGMS) Status Update summary

Strategic Focus and Leadership Changes

• Announced exclusive focus on autoimmunity, deprioritizing oncology programs such as aplitabart to concentrate resources on T cell engagers, primarily imvotamab and IGM-2644.

• Mary Beth Harler, M.D., appointed CEO, bringing extensive immunology and drug development experience; other key executives are stepping down and will remain as consultants.

• Broader team changes and gratitude expressed to outgoing leaders.

Pipeline and Clinical Development

• Imvotamab (CD20 x CD3) is in clinical trials for systemic lupus erythematosus, rheumatoid arthritis, and myositis, with data expected late 2024 or early 2025.

• IGM-2644 (CD38 x CD3) is advancing toward a Phase 1 study in generalized myasthenia gravis by end of 2024.

• Three additional IGM-based agonist immunology and inflammation targets are partnered with Sanofi.

• Collaboration with Sanofi continues for IGM-based agonist targets in immunology and inflammation.

Scientific Rationale and Platform Advantages

• Imvotamab demonstrates superior potency over rituximab and IgG-based TCEs in depleting key B cell subsets, including low CD20 expressers and memory B cells.

• Preclinical and in vitro data support deep tissue B-cell depletion and a favorable safety profile, with early safety data from NHL patients showing a manageable CRS rate and no ICANS.

• IGM-2644 targets CD38, offering potential to deplete autoantibody-producing cells not addressed by CD19-targeting therapies and showing promising in vitro potency compared to daratumumab.

• Platform is based on engineered IgM antibodies, which have 10 binding sites versus 2 for conventional IgG, allowing for tailored B cell depletion strategies.