Radioligand Therapy
Targeting the tumors beyond today’s radioligands
De novo cyclic-peptide targeting ligands that carry a therapeutic radioisotope to novel GPCR antigens — a theranostic ¹⁷⁷Lu / ²¹²Pb / ²²⁵Ac therapy paired with a ⁶⁸Ga PET companion, for the tumor antigens today's radioligand therapy doesn't reach.
How it works: a de novo cyclic-peptide targeting ligand binds a tumor-selective GPCR, the receptor internalizes the bound payload, and ¹⁷⁷Lu delivers a localized radiation dose that breaks tumor-cell DNA — with a ⁶⁸Ga companion diagnostic to select patients and guide dose.
Radioligand therapy works — the antigen map is the bottleneck
Lutathera and Pluvicto proved that targeted ¹⁷⁷Lu radiotherapy can deliver benefit where chemotherapy fails, opening a validated regulatory and manufacturing pathway. But today’s approved radioligands address only a small fraction of addressable oncology — the rest of the tumor-antigen landscape remains out of reach.
GPCRs are the largest druggable family, with highly tumor-selective expression profiles — and our de novo design approach lets us build novel, patent-pending targeting ligands for them from scratch, before any wet-lab spend.
Our approach
De novo targeting ligands
Cyclic peptides designed from scratch to a chosen GPCR — novel, patent-pending compositions, engineered for selectivity against the closest receptor relatives.
Theranostic by design
A chelator handle carries the matched radioisotope — ¹⁷⁷Lu, ²¹²Pb, or ²²⁵Ac for therapy, ⁶⁸Ga for a companion PET diagnostic that selects patients and guides dose.
Therapeutic window
Tumor-selective GPCRs with low normal-tissue expression — the basis for a favorable radiation therapeutic window, assessed target by target.
RLT programs
Full pipelineAX-RLT-001
Patent pendingTarget
Undisclosed
Indication
Castration-resistant prostate cancer (beyond current radioligand therapy)
A prostate antigen retained in CRPC — where today’s approved radioligands lose their target.
AX-RLT-002
Patent pendingTarget
Undisclosed
Indication
Prostate / ER+ breast cancer
A complement to today’s approved radioligands — a de novo ligand, designed selective and salivary-sparing.
AX-RLT-003
Patent pendingTarget
Undisclosed
Indication
Endometrial carcinoma
Among the cleanest normal-tissue windows in the portfolio.
Preclinical · de novo-designed cyclic peptides · ¹⁷⁷Lu / ²¹²Pb / ²²⁵Ac therapy + ⁶⁸Ga companion diagnostic · sequences and data shared under CDA.
Building an RLT pipeline?
We partner on novel, ownable GPCR antigens — out-license, option, or co-develop. Detailed data and IP status are shared under CDA.
Partner with Us