Abstract
Purpose: Radioimmunotherapy (RIT) delivered by radiometal immunoconjugates (RICs) is dose limited by deposition and retention of radioactivity in normal tissues. In order to increase elimination of radioactivity from the liver and body, a peptide having a specific cathepsin B cleavage site was placed between the radiometal chelate, 111In-DOTA, and the panadenocarcinoma monoclonal antibody (MAb), m170. Experimental design: Indium-111 ( 111In)-1,4,7,10-tetraazacyclododecane-N,N′,N″, N‴-tetraacetic acid (DOTA)-2-iminothiolane (2IT)-m170 and 111In-DOTA-peptide-m170, representing the same MAb and chelate without and with a cleavable linkage, were studied in athymic mice and patients with breast or prostate cancer. Pharmacokinetics, cumulated activities and therapeutic indices (TI), were evaluated. Cumulated activities in the liver and tumors were calculated and used as a surrogate for radiation dose. Results: Except for liver, the pharmacokinetics of 111In-DOTA-peptide-m170 were similar to those of the 111In-2IT-2-[p(bromoacetamido)benzyl]-1,4,7, 10-tetraazocyclododecane-N,N′,N″,N‴-tetraacetic acid-m170 (111In-2IT-BAD-m170) in mice and patients. Liver cumulated activities for 111In-DOTA-peptide-m170 were consistently decreased when compared to those for 111In-2IT-BAD-m170, reductions varying between 22-30%. Cumulated activities for 111In-DOTA-peptide-m170 in the malignant tumors of the patients were as great as those for 111In-2IT-BAD-m170, so that the tumor-to-liver cumulated activity ratios (therapeutic indices) were better for 111In-DOTA-peptide-m170. Conclusions: A cathepsin-B-cleavable peptide used to link chelated 111In to MAb, m170, reduced liver cumulated activity (radiation dose) and improved the TI. This novel linker illustrates the importance of linker technology in the development of safer RICs for cancer therapy.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 85-92 |
| Number of pages | 8 |
| Journal | Cancer Biotherapy and Radiopharmaceuticals |
| Volume | 19 |
| Issue number | 1 |
| DOIs | |
| State | Published - 2004 |
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Keywords
- Antibody
- Cancer
- Indium-111
- Linker
- Radioimmunotherapy
ASJC Scopus subject areas
- Cancer Research
- Oncology
- Pharmacology
Cite this
Evaluation of a Cathepsin-Cleavable Peptide Linked Radioimmunoconjugate of a Panadenocarcinoma MAb, m170, in Mice and Patients. / Denardo, Gerald L; DeNardo, Sally J.
In: Cancer Biotherapy and Radiopharmaceuticals, Vol. 19, No. 1, 2004, p. 85-92.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Evaluation of a Cathepsin-Cleavable Peptide Linked Radioimmunoconjugate of a Panadenocarcinoma MAb, m170, in Mice and Patients
AU - Denardo, Gerald L
AU - DeNardo, Sally J.
PY - 2004
Y1 - 2004
N2 - Purpose: Radioimmunotherapy (RIT) delivered by radiometal immunoconjugates (RICs) is dose limited by deposition and retention of radioactivity in normal tissues. In order to increase elimination of radioactivity from the liver and body, a peptide having a specific cathepsin B cleavage site was placed between the radiometal chelate, 111In-DOTA, and the panadenocarcinoma monoclonal antibody (MAb), m170. Experimental design: Indium-111 ( 111In)-1,4,7,10-tetraazacyclododecane-N,N′,N″, N‴-tetraacetic acid (DOTA)-2-iminothiolane (2IT)-m170 and 111In-DOTA-peptide-m170, representing the same MAb and chelate without and with a cleavable linkage, were studied in athymic mice and patients with breast or prostate cancer. Pharmacokinetics, cumulated activities and therapeutic indices (TI), were evaluated. Cumulated activities in the liver and tumors were calculated and used as a surrogate for radiation dose. Results: Except for liver, the pharmacokinetics of 111In-DOTA-peptide-m170 were similar to those of the 111In-2IT-2-[p(bromoacetamido)benzyl]-1,4,7, 10-tetraazocyclododecane-N,N′,N″,N‴-tetraacetic acid-m170 (111In-2IT-BAD-m170) in mice and patients. Liver cumulated activities for 111In-DOTA-peptide-m170 were consistently decreased when compared to those for 111In-2IT-BAD-m170, reductions varying between 22-30%. Cumulated activities for 111In-DOTA-peptide-m170 in the malignant tumors of the patients were as great as those for 111In-2IT-BAD-m170, so that the tumor-to-liver cumulated activity ratios (therapeutic indices) were better for 111In-DOTA-peptide-m170. Conclusions: A cathepsin-B-cleavable peptide used to link chelated 111In to MAb, m170, reduced liver cumulated activity (radiation dose) and improved the TI. This novel linker illustrates the importance of linker technology in the development of safer RICs for cancer therapy.
AB - Purpose: Radioimmunotherapy (RIT) delivered by radiometal immunoconjugates (RICs) is dose limited by deposition and retention of radioactivity in normal tissues. In order to increase elimination of radioactivity from the liver and body, a peptide having a specific cathepsin B cleavage site was placed between the radiometal chelate, 111In-DOTA, and the panadenocarcinoma monoclonal antibody (MAb), m170. Experimental design: Indium-111 ( 111In)-1,4,7,10-tetraazacyclododecane-N,N′,N″, N‴-tetraacetic acid (DOTA)-2-iminothiolane (2IT)-m170 and 111In-DOTA-peptide-m170, representing the same MAb and chelate without and with a cleavable linkage, were studied in athymic mice and patients with breast or prostate cancer. Pharmacokinetics, cumulated activities and therapeutic indices (TI), were evaluated. Cumulated activities in the liver and tumors were calculated and used as a surrogate for radiation dose. Results: Except for liver, the pharmacokinetics of 111In-DOTA-peptide-m170 were similar to those of the 111In-2IT-2-[p(bromoacetamido)benzyl]-1,4,7, 10-tetraazocyclododecane-N,N′,N″,N‴-tetraacetic acid-m170 (111In-2IT-BAD-m170) in mice and patients. Liver cumulated activities for 111In-DOTA-peptide-m170 were consistently decreased when compared to those for 111In-2IT-BAD-m170, reductions varying between 22-30%. Cumulated activities for 111In-DOTA-peptide-m170 in the malignant tumors of the patients were as great as those for 111In-2IT-BAD-m170, so that the tumor-to-liver cumulated activity ratios (therapeutic indices) were better for 111In-DOTA-peptide-m170. Conclusions: A cathepsin-B-cleavable peptide used to link chelated 111In to MAb, m170, reduced liver cumulated activity (radiation dose) and improved the TI. This novel linker illustrates the importance of linker technology in the development of safer RICs for cancer therapy.
KW - Antibody
KW - Cancer
KW - Indium-111
KW - Linker
KW - Radioimmunotherapy
UR - http://www.scopus.com/inward/record.url?scp=1542743561&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=1542743561&partnerID=8YFLogxK
U2 - 10.1089/108497804773391720
DO - 10.1089/108497804773391720
M3 - Article
C2 - 15068616
AN - SCOPUS:1542743561
VL - 19
SP - 85
EP - 92
JO - Cancer Biotherapy and Radiopharmaceuticals
JF - Cancer Biotherapy and Radiopharmaceuticals
SN - 1084-9785
IS - 1
ER -