Study Background

This Phase 1 clinical trial involves performing image-guided biopsies on patients with metastatic castration-resistant prostate cancer (mCRPC) after treatment with 177Lutetium-PSMA radioligand therapy, in order to elucidate the mechanisms of treatment resistance. Image-guided biopsy is a method of directly collecting tumor tissue after radiation therapy and analyzing it microscopically, allowing for real-time assessment of treatment efficacy. This approach differs from conventional methods that only estimate treatment response and represents an attempt to understand resistance at the actual tumor cell level.

Need for Exploring Resistance Mechanisms

Currently, 177Lu-PSMA therapy selectively destroys cancer cells by targeting prostate-specific membrane antigen (PSMA); however, in some patients, the disease progresses even after treatment. Resistance can occur through various mechanisms, including decreased PSMA expression, activation of DNA repair pathways, or changes in the tumor microenvironment. By directly confirming these changes through image-guided biopsy, key data can be provided for designing personalized treatment strategies in the future.

Differentiation from Current Standard Treatment

For mCRPC patients, hormone therapy, chemotherapy, and recently approved PSMA-based radioligand therapy are used as standard treatments. However, existing treatments do not reflect the individual tumor characteristics of each patient, limiting alternative options in case of treatment failure. This study compares tissues before and after treatment, which will establish a basis for early identification of individual resistance patterns and propose additional targeted therapies or combination therapies based on these patterns.

Future Market and Research Impact

If the resistance mechanisms are clearly elucidated, pharmaceutical companies can quickly pursue the development of new drugs targeting these mechanisms or combination strategies with existing radioligand therapies. This has the potential to contribute to the expansion of the indications for 177Lu-PSMA therapy and the establishment of a patient-personalized treatment model, which could significantly expand the market size for mCRPC treatment. Furthermore, the image-guided biopsy technique itself can be applied to other types of cancer, potentially promoting a paradigm shift in overall cancer treatment.