Table 1 Recently studied radionuclide delivery systems based on antibodies and antibody fragments

⁸⁹Z

Diabody

Chelation (DFO)

PET

Molecular imaging of CD4+ T cells throughout the body has implications for monitoring autoimmune disease and immunotherapy of cancer

[46]

⁸⁹Z

Diabody

Chelation (DFO)

PET

PET based detection of PSMA in prostatic tumor models

[48]

¹⁷⁷Lu

Nanobody

Chelation (DTPA)

RIT

¹⁷⁷Lu-DTPA-2Rs15d nanobody-based targeted radionuclide therapy in mice bearing small established HER2 positive tumors led to an almost complete blockade of tumor growth

[58]

⁶⁸Ga

Nanobody

Chelation (NOTA)

PET

The described agents were capable of highly specific accumulation in the tumor areas and reduced kidney retention comparing to the previously reported Nanobodies due to the removal of histidine tag. Overall the reported tracer proved to be safe in mouse toxicity and dosimetry studies and suggested for further clinical trials

[59]

¹⁷⁷Lu

Affibody ZHER_2:342

Chelation (maGGG and maGSG)

RIT

Successful targeting of HER2 positive microxenografts was confirmed by gamma-camera imaging, and the treatment extended survival in mice with high and low HER2 expressing tumors. However, overall mortality was caused by bone marrow toxicity

[67]

¹¹¹In

bsAbs

Chelation (DOTA)

SPECT, RIT

In a first-in-human Phase I study, anti-CEA with anti-HSG TF2 was evaluated in patients with colorectal cancer, with ¹¹¹In-IMP288 used in the imaging cycle and ¹⁷⁷Lu-IMP288 in the following therapy cycle

[73]

²¹³Bi

bsAbs

Chelation (DOTA)

RIT

The authors demonstrated the usage of Tri-Fab antibody which allowed pretargeting of radiolabeled hapten–peptide IMP-288. In vivo α-emitting hapten ²¹³Bi-IMP288 was shown to be at least as effective as β-emitting hapten ¹⁷⁷Lu-IMP288

[75]