Alligator Bioscience Announces Trial Update and Early Readout for ATOR-1017 Confirming Biomarker, Safety & Tolerability Data

Lund, Sweden, December 16, 2021 – Alligator Bioscience (Nasdaq Stockholm: ATORX) today announced an update on the on-going clinical Phase I trial with the 4-1BB (CD137) drug candidate ATOR-1017, which is developed as a tumor-directed therapy for metastatic cancer. The early readout data corroborates previous data on biomarkers, safety and tolerability, sustaining a safety profile up to and including a dose of 360 mg with no dose limiting toxicities reported.

The Phase I study with ATOR-1017 is a first-in-human, open-label, dose escalation study in patients with advanced solid cancer (NCT04144842). The primary objective of the study is to investigate the safety and tolerability of ATOR-1017, and to determine the recommended dose for subsequent Phase II studies. The results from the current evaluation shows that ATOR-1017 has an encouraging safety profile. Again, there was no dose-limiting toxicity or severe immune-related adverse events. The results support data from earlier read-outs that ATOR-1017 exhibits a favorable pharmacokinetic profile. Additionally, it confirms and extends previous biomarker data demonstrating proof of mechanism of ATOR-1017, including increased proliferation of circulating T-cells and dose-dependent increases in soluble 4-1BB, both biomarkers of T-cell activation.  A full data read-out is expected in Q1 2022.

Earlier this year, the Company announced results that validated the therapeutic potential of ATOR-1017 demonstrating a very favorable safety profile combined with clear signs of proof of mechanism, as activation of T cells in the circulation was observed across active dose levels of ATOR-1017 in a poster presentation at the 2021 ASCO Annual Meeting (link to press release).

“We are extremely pleased with the confirmatory data as it strengthens the case for the safety and tolerability as well as confirming the proof of mechanism of ATOR-1017. We are excited by this outcome and are working hard on completing this study and determining the dose for a subsequent Phase II program,” said Søren Bregenholt, CEO of Alligator Bioscience.

For further information, please contact:

Julie Silber, Investor Relations

Phone: +46 46-540 82 23


About Alligator Bioscience

Alligator Bioscience AB is a clinical-stage biotechnology company developing tumor-directed immuno-oncology antibody drugs. Alligator’s pipeline includes the two key assets mitazalimab, a CD40 agonist, and ATOR-1017, a 4-1BB agonist. Furthermore, Alligator is co-developing ALG.APV-527 with Aptevo Therapeutics Inc., several undisclosed molecules based on its proprietary technology platform, Neo-X-Prime™, with MacroGenics Inc. and novel drug candidates based on the RUBY™ bispecific platform with Orion Corporation. Out licensed programs include AC101, in phase II development, by Shanghai Henlius Biotech Inc. and an undisclosed target to Biotheus Inc. Alligator Bioscience’s shares are listed on Nasdaq Stockholm (ATORX) and is headquartered in Lund, Sweden.

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Updated 2021-12-16