A28 is Developing a Targeted Lytic Peptide Platform for the Treatment of Multiple Cancer Types.

Host defense peptides (HDPs) exist in many species of vertebrates, invertebrates, and plants. These compounds are comprised of short chains of amino acids and share common features of cationicity, hydrophobicity, and an amphipathic structure.

A28’s targeted lytic peptide platform is based on the direct cell killing capabilities of many naturally occurring HDPs, and is elicited by the electrostatic reaction between our CLYP-71 cationic lytic peptide and negatively charged cancer cells. The A28 product portfolio consists of conjugations of CLYP-71 and multiple targeting units intended to bind to surface-associated receptors found on the cell membranes of many types of solid tumor cancers and hematological malignancies.

AT-101: Our Lead Compound

Our lead product AT-101, in late-stage clinical development, is a targeted agent that rapidly and selectively kills cancer cells, without harming healthy cells. Phase 1 and Phase 2 studies with more than 85 patients demonstrated promising results both in terms of safety and efficacy of AT-101. Most promisingly, in our Phase 2 study, the subset of patients with metastatic ovarian cancer with liver metastases had a 69% overall response rate (ORR) in combination with chemotherapy, versus a 17% ORR with chemotherapy alone, and a 61% increase in overall survival (OS).

Safety: No systemic side effects, off target effects, immune suppression, or liver toxicity, not toxic in combination with other cancer treatment regimens, not antigenic.

Pharmacokinetics: Biodistribution to liver for up to 72 hours. Can control exposure with increased infusion time.

Anti-cancer activity: Causes immunogenic cell death not dependent upon replication, reverses multi-drug resistance, and synergizes with multiple classes of cancer drugs.

CMC/Manufacturing: Manufactured by solid chemistry, production scaled to Kg levels. Stable for at least 3 years. Water soluble, formulated as lyophilized cake.

AT-101’s Unique Mechanism of Action

AT-101 binds to LHRH receptors found on the cell membranes of the most prevalent types of solid tumor cancers, causing rapid immunogenic cell death.




Cancer cells are negatively charged due to their metabolism, and numerous cancer types over-express LHRH receptors on their cell membranes.




AT-101 targeting domain binds to the LHRH receptor, and the positively charged lytic domain is attracted to the negatively charged cancer cell membrane




Once AT-101 is bound to the cancer cell, the lytic peptide disrupts the cancer cell membrane, leading to rapid, immunogenic cell death and the release of tumor neoantigens

Learn Why Targeted Lytic Peptides Are a Promising Treatment for Multiple Cancer Types

Interested in learning more about the A28 targeted lytic peptide platform? We would be pleased to have an opportunity to share our compelling story, platform, pipeline, and data with you.

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