Anti-L1CAM radioimmunotherapy is more effective with the radiolanthanide terbium-161 compared to lutetium-177 in an ovarian cancer model

Abstract

Our study is the first to show that anti-L1CAM (161)Tb RIT is more effective compared to (177)Lu RIT in ovarian cancer xenografts. These results suggest that (161)Tb is a promising candidate for future clinical applications in combination with internalising antibodies.

Dose Deposits from 90Y, 177Lu, 111In, and 161Tb in Micrometastases of Various Sizes: Implications for Radiopharmaceutical Therapy

“…For example, 161 Tb-anti-L1CAM antibodies were more effective than 177 Lu-anti-L1CAM at inhibiting the growth of subcutaneous xenografts of ovarian cancer (19). In another study, the radioactivity concentration necessary to achieve half-maximal inhibition of tumor cells was lower with 161 Tb-labeled than with 177 Lu-labeled radiofolate conjugates (20).…”

“…Similarly to 177 Lu, 161 Tb can be stably linked to various targeting molecules (19,20). 161 Tb has a small percentage of photons that would enable posttherapy imaging (Table 1).…”

“…The radiolanthanide 161 Tb is a medium-energy b 2 emitter similar to 177 Lu but emits a higher percentage of conversion and Auger electrons. Some in vivo studies suggested that 161 Tb might outperform 177 Lu (19,20). The aim of this Monte Carlo simulation study was to compare the effectiveness of 90 Y, 177 Lu, 111 In, and 161 Tb at irradiating micrometastases of various sizes.…”

The on-line low temperature nuclear orientation facility NICOLE

“…Thus isotopes that emit conversion electrons followed by cascades of Auger electrons are of great interest. Preclinical experiments study the therapeutic effects and side effects of different radionuclides as function of activity [36,37], but eventually this activity has to be converted into dose for direct dose/effect comparisons. This requires precise knowledge of the intensities of all conversion electrons and the resulting Auger cascades.…”

Radiochemical Separation of ¹⁶¹Tb from Gd/Tb Matrix Using Ln Resin Column

“…The dosimetric evaluation of therapeutic efficiency of electron emitting radiolanthanides shows that 161 Tb provides better energy transfer in small tumor than 177 Lu because of the high conversion and Auger electrons [12][13]. Accordingly, 161 Tb may be useful as a complement to 177 Lu due to its good tumor-to-normal-tissue mean absorbed dose ratios (TNDs) profile [11].…”