Castration Resistant Metastatic Prostate Cancer

This is a Phase 1b, multi-center, open-label study to evaluate the safety, tolerability, dosimetry, and pharmacokinetics (PK) of \[64Cu\]Cu-AKY-2519 and/or \[225Ac\]Ac-AKY-2519, as well as the preliminary anti-tumor activity of \[225Ac\]Ac-AKY-2519 in participants with metastatic castration-resistant prostate cancer (mCRPC) with and without prior exposure to 177Lu-PSMA-617 (PLUVICTO™).

Asymptomatic men without pain due to prostate cancer progressing with metastatic CRPC after treatment with combination or sequential ADT + Abi will be treated on a randomized, open label study to determine if sequential treatment with high dose T and Enza will improve primary and secondary objectives vs. continuous Enza as standard therapy.

Prostate cancer is the most common cancer in men. Its incidence is rising as the population ages. In the localized stage, the 5-year overall survival rate (OS) is 98%. Metastatic progression and resistance to castration have a negative impact on prognosis. Despite recent advances in management, the 5-year OS is around 30%. Therapeutic advances in this indication have been made mainly by the use of taxanes and second-generation hormone therapy. These treatments have improved OS and progression-free survival (PFS). They are now used as standard therapy. More recently, the Phase III VISION trial confirmed the improvement in OS and radiological PFS achieved by treatment with the radioligand 177Lutetium-PSMA-617 (Lu-PSMA) in patients with advanced metastatic castration-resistant prostate cancer (mCRPC). This treatment is currently available in early access in France. Despite encouraging results, 40% of patients will not respond to Lu-PSMA, and there are currently no validated predictive factors. Studies are currently on going, but the identification of biomarkers seems necessary to better stratify risk in these patients. Numerous tissue prognostic tests based on molecular characteristics or cell proliferation are emerging with this in mind. At present, molecular profiling is not a routine technique for prostate cancer, as it is for other solid cancers. At an early stage, the Decipher® Genomic classification tool has shown prognostic utility independently of therapeutic and clinico-pathological data. According to recent studies, methylome analysis would enable the subdivision of mCRPCs and could help identify new therapeutic targets. In the metastatic phase, certain molecular abnormalities involving DNA repair genes are predictive of response to PARP inhibitors. Molecular analysis (mutations, copy number alterations, gene expression, DNA methylation) could therefore be useful in optimizing the management of mCRPC patients treated with Lu-PSMA. If reliable molecular abnormalities are identified on tissue, a diagnostic technique based on circulating tumor DNA (ctDNA) analysis will be useful in decision-making for these patients. A biological collection will therefore be created during the course of this study, with a view to using ctDNA analysis in subsequent research.

In patients with metastatic prostate cancer (PCa) who receive androgen deprivation therapy (ADT), the sensitivity to castration will eventually disappear due to the selection of castration-refractory clones. This will lead to the stage of metastatic castration-refractory prostate can-cer (mCRPC), which is incurable and results in a median overall survival of 2-3 years. Treatment options for patients with mCRPC include several systemic agents, such as andro-gen receptor-targeted agents (ARTA), chemotherapy (docetaxel, cabazitaxel) and bone-targeting agents (radium- 223). Clinical progression and, to a lesser extent, biochemical pro-gression traditionally imply a switch to the next line systemic treatment (NEST). Within patients with mCRPC, there is a subgroup showing oligo-progression, defined as the progression of up to 3 lesions, including both metastatic and/or local relapse. Oligoprogression reflects a heterogeneous treatment response, which, in turn, reflects the heterogeneity of the clonogenic cells that give rise to mCRPC. Retrospective studies suggest that metastasis-directed radiotherapy (MDRT) to these oligoprogressive lesions delayed the need for NEST. Recently, promising results were published on the use of MDRT in the oligopro-gressive mCRPC (omCRPC) setting, with a NEST-free survival (NEST-FS) of 21 months in well selected patients. Currently, in The Netherlands, patients with omCRPC are frequently referred and treated with MDRT, but a clear treatment protocol and inclusion/selection criteria are missing. Moreover, the exact benefit of MDRT in patients with omCRPC remains unclear, as prospective evi-dence for MDRT in omCRPC is lacking.