Abzena And Telix Pharma Sign License Agreement For Abzena’s Prostate-Specific Membrane Antigen Antibodies

Telix to develop products for imaging and treatment of prostate cancer

CAMBRIDGE, England & MELBOURNE, Australia--(BUSINESS WIRE)--Abzena plc (AIM: ABZA, ‘Abzena’), the life sciences group providing services and technologies to enable the development and manufacture of biopharmaceutical products, has signed a licence agreement with Telix Pharmaceuticals Limited (‘Telix’), a biopharmaceutical company specializing in the development and commercialisation of radiopharmaceuticals for diagnostic (imaging) and therapeutic use (the “Agreement”).

“We believe our expertise and integrated offering in biology, chemistry and biomanufacturing bring important capabilities to Telix, as it develops its exciting portfolio of next generation oncology radiopharmaceutical products.”

Under the terms of the Agreement, Abzena has granted Telix an exclusive worldwide, royalty bearing, sub-licensable licence to its prostate-specific membrane antigen (‘PSMA’) antibodies in the field of radio-immunoconjugation. The PSMA antibodies were created using Abzena’s Composite Human Antibody™ technology.

The Agreement has the potential, subject to successful development, to deliver in excess of US$65 million in licence fees and milestone payments to Abzena over its life, based on achievement of certain development, regulatory and commercial milestones, in addition to royalties on net sales of approved products. The parties have also implemented a separate services agreement to develop these products further.

A radio-immunoconjugate is created by attaching a radioactive isotope to a biological targeting entity e.g. a monoclonal antibody. The benefit of such a combination is that a radioactive substance can be carried directly to a cancer cell with a high degree of specificity and selectivity. The mechanism of action includes a combination of DNA damage to tumour cells and an immune-stimulating antigen release as the tumour micro-environment is remodelled.

The Abzena antibodies subject to the Agreement are prostate cancer-specific, therefore, depending on the type of radioactivity Telix attaches to the product, the resulting radio-immunoconjugate can either be used to image where cancerous cells are in the prostate or to kill the cancer with great precision, minimising the radiation exposure to healthy tissue.

Monoclonal antibodies remain one of the most versatile platforms for the design of targeted radiopharmaceuticals. This is due to their high in-vivo stability, prolonged circulation time in blood and comparative ease of chemical functionalisation, along with a high antigen specificity and affinity.

Christian Behrenbruch, CEO of Telix Pharmaceuticals, commented:

“Radio-immunoconjugates have tremendous potential as one of the most adaptable site specific, precision medicines and, in prostate cancer, PSMA is increasingly recognised as an important target.

“This deal with Abzena significantly reinforces Telix’s development focus in prostate cancer. Our approach to delivering molecularly-targeted radiation not only represents the next frontier for radiation oncology therapy, but also has an important nexus with the rapidly developing field of cancer immunotherapy. Our mission is to build on existing clinical experience with PSMA antibody-directed radiation to create a product that can be manufactured effectively and with an optimised efficacy profile.

“We chose to work with Abzena because of its proven expertise in antibody engineering and conjugation, a track record which is reflected by the fact that there are 12 antibody drugs in the clinic that harness Abzena’s technology”.

John Burt, CEO of Abzena, said:

“We believe our expertise and integrated offering in biology, chemistry and biomanufacturing bring important capabilities to Telix, as it develops its exciting portfolio of next generation oncology radiopharmaceutical products.

“This agreement with Telix represents a further example of Abzena licensing its proprietary technology to a partner, while the concurrent entry into a new services agreement with Telix for further development work reaffirms the validity of our combined services and technology licensing business model.”

Notes to Editors

About Prostate-Specific Membrane Antigen (PSMA)

PSMA is a cell surface antigen that has relatively little normal expression in normal tissues and represents a validated and highly promising target for a range of therapeutic strategies, especially radiopharmaceuticals. PSMA expression has been detected in a limited range of normal tissues including benign prostatic epithelium, renal proximal tubule, pancreas, small bowel and brain (a subset of astrocytes). However, these normal sites express PSMA at levels 2–3 orders of magnitude lower than that observed in prostate cancer¹

Antibody-directed cytotoxicity (whether from conjugated radiation or other therapeutic payloads) offers several advantages over small molecule or peptide-based delivery approaches. Normal tissue PSMA sites are effectively inaccessible to circulating mAbs (monoclonal antibodies) and PSMA expression by astrocytes in the brain is similarly sequestered behind the blood-brain barrier. Consequently, antibodies to PSMA are functionally tumour-specific, whereas small molecule and peptide therapies targeting PSMA, with various isotopes, have demonstrated serious off-target effects, such as pancreatitis, nephrotoxicity and permanent salivary gland ablation. These considerations are particularly important for developing PSMA-targeting agents with high-energy nuclides such as alpha-particle emitters.

About Abzena PLC

Abzena (AIM: ABZA) provides proprietary technologies and complementary services to enable the development and manufacture of biopharmaceutical products. The term ‘Abzena Inside’ is used by Abzena to describe products that have been created using its proprietary technologies and are being developed by its partners, and include Composite Human Antibodies™ and ThioBridge™ Antibody Drug Conjugates (ADCs). Abzena has the potential to earn future licence fees, milestone payments and/or royalties on ‘Abzena Inside’ products.

Abzena offers the following services and technologies across its principal sites in Cambridge (UK), San Diego, California (USA) and Bristol, Pennsylvania (USA):

• Immunology research studies, including immunogenicity assessment of candidate biopharmaceutical products;

• Protein engineering to create humanized antibodies and deimmunised therapeutic proteins;

• Cell line development for the manufacture of recombinant proteins and antibodies;

• Contract process development and GMP manufacture of biopharmaceuticals, including monoclonal antibodies and recombinant proteins for preclinical and clinical studies;

• Contract synthetic chemistry and bioconjugation research services, focused on antibody-drug conjugates (ADCs); and

• Proprietary site-specific conjugation technologies and novel payloads for ADC development; and GMP manufacturer of ADC linkers, payloads & combined linker-payloads.

For more information, please see www.abzena.com

About Telix Pharmaceuticals Limited

Telix is a clinical-stage biopharmaceutical company headquartered in Melbourne, Australia. Telix is developing an advanced portfolio of clinical-stage products that address significant unmet medical needs in renal, prostate and brain (glioblastoma) cancers. Telix’s pipeline consists of “theranostic” radiopharmaceuticals, agents that can be used both diagnostically (via PET imaging) and therapeutically for patient benefit. Telix is an unlisted public company. For more information go to www.telixpharma.com.

¹ Source: Holland et. al. J Nucl Med. 2010 August ; 51(8): 1293–1300