Overview

APIM Therapeutics is developing a series of proprietary Protein Protein Interaction (PPI) blocking peptides targeting complexes formed between PCNA¹ (Proliferating Cell Nuclear Antigen) and proteins bearing a novel PCNA-interacting Peptide Motif called APIM² (AlkB homolog 2 PCNA Interacting Motif). These compounds are particularly relevant for the treatment of hyper-proliferative disorders such as cancer.

Our therapeutic candidate, ATX-101, is a first-in class PCNA/APIM PPI blocking compound currently being developed for the treatment of several cancer indications either alone or in combination with selected anti-cancer agents. A snapshot of the drug pipeline of APIM Therapeutics is presented below. The company has recently concluded a phase I, first-in-human study in patients with advanced solid tumors. Currently, two clinical trials are in progress:

1. A phase Ib/IIa study in platinum-sensitive ovarian cancer conducted in Australia/APAC, testing ATX-101 in combination with platinum-based chemotherapy.

2. A phase II study in sarcoma (lipo-, and leiomyosarcoma) conducted as an Investigator Initiated Study by the Columbia University Irving Medical Center, evaluating ATX-101 as monotherapy.

Other indications/combinations are also of further interest for future applications and are currently being planned.

For more information on our pipeline, feel free to contact us directly.

PCNA is currently recognized as a "hub" protein involved in several essential processes such as DNA replication, DNA repair, epigenetics as well as apoptosis, glycolysis and signaling. The essential roles of PCNA during cellular stress and replication make it a potential drug target relevant for multiple cancer indications.
There are two known and highly conserved PCNA interacting motifs: the PCNA-interacting peptide (PIP)-box and the AlkB homologue 2 PCNA-interacting motif (APIM). Present in more than 600 proteins, these motifs share overalapping binding sites on PCNA. Peptides and/or small molecules that bind with high affinity to this binding site will inhibit the majority of PCNA-protein interactions, and thereby inhibit essential cellular functions. PIP-box is more relevant for housekeeping PCNA functions, whereas APIM plays a fundamental role in stress e.g. DNA damage or cancer treatment stress.