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selectION, Inc., Reports Interim Safety and Tolerability Results of Phase 1b Clinical Trial in Atopic Dermatitis

  • Ongoing phase 1b trial is designed to evaluate safety, tolerability, and efficacy of si-544 in T-cell mediated autoimmunity
  • Dosing of MAD stage has been initiated; first results expected for late summer 2023

– San Diego, CA, USA, and Munich, Germany – May 30, 2023 – selectION, Inc., a clinical-stage biopharmaceutical company developing novel treatments of T-cell mediated autoimmune diseases, today announced excellent initial safety results of the single ascending dose (SAD) stage in the Phase 1b trial of its drug candidate si-544 in atopic dermatitis patients. si-544 is a selectivity-optimized peptide blocking the ion channel Kv1.3.

The ongoing Phase 1b trial is a multi-center, double-blind, placebo-controlled study in patients with mild to severe atopic dermatitis. The trial is designed to evaluate safety, tolerability, and efficacy signals of si-544, a high-affinity Kv1.3-blocking peptide with class-leading selectivity.

In the first stage of the trial, no dose limiting toxicities (DLTs), or safety signals have been observed. Based on these encouraging results, the trial now progresses into the multiple ascending dose (MAD) stage, where patients will receive a one-month treatment cycle of si-544, followed by a monitoring period lasting three months.

“The ion channel Kv1.3 controls the activation and proliferation of auto-reactive effector memory T-cells and has been regarded a key target in T-cell autoimmunity for decades,” said Andreas Klostermann, PhD, Chief Scientific Officer, and co-founder of the Company. “So far, it has not been possible to block this ion channel with sufficient selectivity. The initial analysis of safety and tolerability data from 20 patients confirms that si-544 can be safely administered at dose levels sufficient to achieve virtually full Kv1.3 target engagement. To our knowledge, selectION, Inc. is the first to achieve this important goal.”

“We are encouraged by the safety profile observed for si-544 so far,” said Antonius Schuh, PhD, Chairman and CEO of selectION, Inc. “The data provide initial clinical validation that we can safely and selectively target autoimmune disease associated chronically activated effector memory T-cells. This is a key milestone in the development of si-544. We will continue our path to deliver a potent and immune-selective therapy which maintains a patient’s general immunocompetency, and we believe that si-544 has the potential to significantly improve safety and outcomes for patients suffering from a wide range of autoimmune diseases, including atopic dermatitis, psoriasis, psoriatic arthritis, rheumatoid arthritis, multiple sclerosis, and many others.”


About selectION, Inc.

selectION, Inc., is a clinical-stage biopharmaceutical company developing novel peptide therapies for autoimmune diseases and selected cancer indications by targeting autoreactive, chronically activated T-cells.

The Company has established an efficient, unique technology platform to develop potent and highly selective peptide blockers for ion channels involved in various diseases. The platform enables to systematically optimize target selectivity, providing the opportunity to develop drugs with significantly improved efficacy and safety profiles.

selectION, Inc., is supported by SDL Ventures and Global Source Ventures. The Company is headquartered in San Diego, CA, USA, with a clinical R&D subsidiary in Munich/Martinsried, Germany.

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About si-544

si-544, the Company´s drug candidate, is blocking Kv1.3, a specific ion channel involved in the activation and proliferation of TEM cells. TEM cells lie at the root of many autoimmune indications such as atopic dermatitis, psoriasis, rheumatoid arthritis, or multiple sclerosis, but also of certain rare cancers like lymphomas.

si-544 has demonstrated excellent efficacy in animal and human T-cell models.
The compound is a potent immuno-selective agent addressing a significant unmet medical need by functionally inhibiting and eliminating disease-specific, chronically activated TEM cells while maintaining full immunocompetence.


Media Contact:
Dr. Ludger Wess / Ines-Regina Buth
Managing Partners
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T: +49 40 88 16 59 64 /
T: +49 30 23 63 27 68

Investor Contact:
selectION, Inc.
Steve Zaniboni (CFO)
[email protected]
T: +1 858 967 8014