Radiopharm Theranostics confirms DUNP19 can halt tumour progression and prolong cancer survival

A study by biotechnology company Radiopharm Theranostics (ASX: RAD) has shown that non-invasive clinical imaging and targeted radioimmunotherapy with lead candidate DUNP19 (RAD 502) is able to halt tumour progression and prolong survival in various cancer models.

Conducted by Dr David Ulmert and colleagues from the University of California, the study demonstrates for the first time how DUNP19 can be used for the detection and targeting of leucine-rich repeat containing 15 (LRRC15)-expressing cancers.

LRRC15 is a cellular marker and novel therapeutic target in solid tumours (such as breast, head and neck, lung and pancreatic) and in cancers that arise from connective tissue (such as osteosarcoma, glioblastoma and melanoma).

DUNP19 (RAD 502) is a highly-specific monoclonal antibody that targets LRRC15 and is believed to offer potential for use as a dual-purpose agent in non-invasive imaging and the theranostic treatment of LRRC15+ aggressive cancers.

In October 2022, Radiopharm demonstrated that LRRC15 plays a key role in defending tumour cells from the body’s immune system.

Novel technique

The latest findings propose a novel technique for imaging and treating a wide range of aggressive tumors that express LRRC15 and have limited current options for targeted therapy.

The results provide early evidence for the ability of Lutetium-177-labelled DUNP19 ([177Lu]-DUNP19) to target pathways involved in immunotherapy resistance and a poor prognosis.

DUNP19 is currently under pre-clinical investigation at Radiopharm as a therapeutic monoclonal antibody labelled with the beta-emitting radioisotope Terbium-161.

Pre-selection of patients

Dr Ulmert said the study may result in the pre-selection of patients with LRRC15-expressing tumors for therapeutic dosing with [177Lu]-DUNP19.

“Our transcriptomic analyses of [177Lu]-DUNP19-treated tumours indicate a reduction in pro-tumorigenic mechanisms, including TGFβ-driven LRRC15+ signature associated with resistance to immunotherapy,” he said.

“These findings underscore the potential of radio-theranostic targeting of LRRC15 as a powerful precision medicine platform.”

Dr Ulmert’s study, titled Development of a LRRC15-Targeted Radio-Immunotheranostic Approach to Deplete Pro-tumorigenic Mechanisms and Immunotherapy Resistance, is available online through biology pre-print server BioRxiv.