Mozart Therapeutics Presents Non-clinical Data on Lead Program, MTX-101 for Treatment of Autoimmune Diseases, at Society of Toxicology Annual Meeting 2024

Findings highlight tolerability and pharmacology of MTX-101 in humanized IL-15 transgenic mouse model

SEATTLE, WA. March 14, 2024 —Mozart Therapeutics, the leading developer of CD8 Treg modulators for the treatment of autoimmune and inflammatory diseases, today announce new non-clinical data for MTX-101. The data will be presented in a late-breaking poster presentation during the Society of Toxicology 63rd Annual Meeting, March 10‒14 in Salt Lake City, Utah.

MTX-101 is an antibody-based bispecific autoimmune checkpoint inhibitor that selectively targets regulatory CD8 T cells. MTX-101 has limited cross-reactivity to its targets in animal models; therefore, a humanized IL-15 transgenic mouse model was utilized for non-clinical assessment of toxicity and pharmacology. 

Presentation highlights include:

  • MTX-101 was well-tolerated following single and multiple doses in the humanized mouse model
  • MTX-101 showed sustained binding to CD8 Treg and did not demonstrate off-target cell effects or cause an increase in detectable pro-inflammatory serum cytokines
  • Serum concentrations of MTX-101 indicated high exposure and PK parameters consistent with antibodies 
  • Data derived from the humanized mouse model aligns with previous in vitro and in vivo findings for MTX-101 

“We are pleased to present early data highlighting the non-clinical safety of MTX-101. Our data underline the utility of the humanized IL-15 transgenic mouse model to assess targeting human immune system receptors with limited cross-reactivity in conventional toxicology species,” said Kristine Swiderek, Ph.D., Chief Scientific Officer at Mozart Therapeutics. “This model enables the non-clinical safety assessment and an understanding of the PK/PD relationship for MTX-101 to inform our clinical development strategy.” 

The poster “Nonclinical Assessment of Toxicity and Pharmacology of MTX-101, a Novel KIRxCD8 Targeting Bispecific CD8 Treg Modulator, in Humanized Mouse
(Abstract #5081, Late-Breaking Session 3, March 14) can be accessed from the Mozart Therapeutics website.  

About MTX-101

MTX-101 is a bispecific CD8 Treg modulator targeting inhibitory KIR and CD8 expressed on regulatory CD8 T cells. This autoimmune checkpoint inhibitor aims to restore the intrinsic functions of regulatory CD8 T cells, acting early in the autoimmune disease process to suppress and eliminate pathogenic autoimmune cells, halt downstream inflammation, and prevent tissue destruction. 

About Mozart Therapeutics

Mozart Therapeutics is focused on developing first-in-class disease-modifying therapies for autoimmune and inflammatory diseases, utilizing a novel approach to restoring immune system function by targeting the CD8 T regulatory network. The company is headquartered in Seattle, WA. For more information, visit and follow the company on LinkedIn @Mozart-tx

Media Contact: 
Julie Rathbun
Rathbun Communications