Santa Ana Bio Announces First Subjects Dosed in Phase 1 Study of SAB01 to Treat Autoimmune Inflammatory Diseases
First-in-class bispecific antibody designed for mast cell elimination without the safety issues associated with
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- First-in-class bispecific antibody designed for mast cell elimination without the safety issues associated with current KIT therapeutics
- Phase 1 single ascending dose study to evaluate the safety, pharmacokinetics, and pharmacodynamics of subcutaneous and intravenous SAB01 in healthy adults
ALAMEDA, Calif., Sept. 14, 2026 (GLOBE NEWSWIRE) — Santa Ana Bio, a precision immunology company developing targeted therapies for patients with autoimmune and inflammatory diseases, today announced that the first cohort has been dosed in the first-in-human Phase 1 study of SAB01, a novel bispecific antibody designed to selectively deplete mast cells through co-engagement of KIT and Siglec-6.
“This marks Santa Ana Bio’s transition into the clinic and opens a new approach to the treatment of mast cell-driven disease,” said Peter Emtage, founder and chief executive officer of Santa Ana Bio. “KIT-targeted antibodies drive rapid and deep responses in chronic urticaria, but KIT isn’t exclusive to mast cells, leading to toxicities from hitting other cell types, including hematopoietic stem cells and melanocytes. SAB01 was designed to uncouple mast cell depletion from broad KIT inhibition.”
SAB01 is a first-in-class bispecific antibody that simultaneously engages KIT and Siglec-6, a receptor pair co-expressed on mast cells and not found together on any other cell type. Avidity-driven co-engagement of both receptors, along with an extended half-life, restricts SAB01 activity to mast cells, selectively and durably depleting them while sparing other KIT-expressing cells.
“The initiation of this Phase 1 healthy volunteer study builds on extensive preclinical work supporting SAB01’s conditional depletion of mast cells,” said Newman Yeilding, M.D., Chief Medical Officer of Santa Ana Bio. “The start of our Phase 1 study of SAB01 is the first step in bringing a truly selective and potentially safer mast cell targeted therapy to patients.”
The Phase 1 clinical trial is a randomized, double-blind, placebo-controlled, single ascending dose trial evaluating subcutaneous and intravenous SAB01 in healthy adult participants. Fifty-six participants will be enrolled across six subcutaneous cohorts and one intravenous cohort of eight participants each, randomized 6:2 to SAB01 or placebo. Further cohorts may be enrolled to evaluate select dose levels based on emerging safety, pharmacokinetic (PK), and pharmacodynamic (PD) data. For additional information on this trial (NCT07815561), please visit www.clinicaltrials.gov.
About Santa Ana Bio
Santa Ana Bio is a biotechnology company developing a pipeline of innovative therapeutics that leverage a multi-omics platform to advance precision medicines for autoimmune and inflammatory diseases. The company’s mission is to improve the lives of patients affected by a wide range of chronic and life-impacting diseases. Santa Ana is advancing a portfolio of innovative product candidates designed to address the biology underlying autoimmune and inflammatory conditions. For more information, visit www.santaana.bio and follow on LinkedIn.
Contact
Neil Abdollahian
nabdollahian@santaana.bio


