Methods: Male Balb/c/nude mice (6–8 weeks old) were inoculated subcutaneously with DU145‐RFP‐Luc cells (5 × 106) in PBS:matrigel (1:1) in the right flank. Once the tumour reached palpable size, the mice were then treated with either chMIL‐38‐DOTA or 177Lu‐chMIL‐38‐DOTA intravenously and sacrificed either on day 3, 5 and 7 or once the control tumour reached 1000 mm3. Tissues were harvested and radioactivity in the organs were measured via gamma counter.
Results: We demonstrated that 177Lu‐chMIL‐38‐DOTA significantly inhibited tumour growth by 50% after a single dose. The inhibition on tumour growth is dose dependent and was observed as early as 6 days post lutetium treatment. Results from biodistribution study showed that the uptake of the antibody by the tumour was the highest across all time points except for spleen at day 7. Independent pathology assessment of tissue toxicity showed minimum cytotoxicity in most tissues.
Conclusion: These data demonstrated the potential usage of targeted beta therapy with 177Lu‐chMIL‐38‐DOTA in prostate cancer.