Data presented on mitazalimab and ATOR-1017 in Two Poster Presentations at SITC Annual Meeting 2022 – November 8-12, 2022

  • Mitazalimab data show the CD40 agonist induces strong immune responses in patients with advanced stage solid tumors and further strengthens its proof of mechanism
  • New ATOR-1017 data show the 4-1BB monoclonal antibody is safe and well tolerated at doses up to 900 mg and demonstrates an excellent clinical profile as a potential best-in-class asset

Lund, Sweden, November 10, 2022 – Alligator Bioscience (Nasdaq Stockholm: ATORX) today announces that data from its two lead clinical assets will feature in two poster presentations at the 2022 SITC (Society for Immunotherapy of Cancer) Annual Meeting, being held in Boston November 8-12.

The first presentation, entitled "Early pharmacodynamic changes measured by RNA sequencing in peripheral blood from patients in a phase 1 study with mitazalimab, a potent CD40 agonistic IgG1 monoclonal antibody", outlines the evaluation of pharmacodynamic changes by measuring RNA sequencing from peripheral blood samples collected both pre- and post-treatment in a dose escalation study of mitazalimab (CD40 mAb) in patients with advanced stage solid tumors (NCT02829099).

The analysis of the RNA sequencing data clearly demonstrates that mitazalimab induces strong immune responses in patients by activating myeloid cells and B cells. The presented gene expression data confirm the biological activity of mitazalimab, further strengthening its proof of mechanism and potential in solid tumors.

The second presentation, entitled "ATOR-1017, a 4-1BB antibody, demonstrates promising safety and proof of mechanism in a first-in-human study in patients with advanced solid malignancies", outlines new results from Alligator’s Phase 1, first-in-human clinical trial with ATOR-1017, a 4-1BB antibody which is being developed as a tumor-directed therapy for advanced/metastatic cancer (NCT04144842).

Overall, the data showed that ATOR-1017 is safe and well-tolerated at doses up to 900 mg and has shown signs of clinical benefit. No dose-limiting toxicity was observed and the maximum tolerated dose was not reached. Stable disease was achieved as best objective response in 13 (52%) of the 25 patients treated with ATOR-1017, which lasted longer than 6 months for 6 (24%) patients. These data warrant further development of ATOR-1017 in combination with other therapeutic approaches in solid tumors.

"Presenting these two sets of data from our lead clinical assets at such a prominent scientific conference like SITC is a welcome validation of the work of Alligator's scientific team and of the potential mitazalimab and ATOR-1017 are both demonstrating in advanced cancers," said Søren Bregenholt, CEO of Alligator Bioscience. "We are very pleased that both data sets support the further advancement of these candidates. We are currently preparing for the next stage of ATOR-1017's development, while enrolment for the Phase 2 part of the OPTIMIZE-1 study of mitazalimab in pancreatic cancer is making great progress."

The information was submitted for publication, through the agency of the contact persons set out below at 3:00 p.m. CET on November 10, 2022.

Updated 2022-11-10