Indian Journal of Medical Research

ORIGINAL ARTICLE
Year
: 2014  |  Volume : 139  |  Issue : 4  |  Page : 544--554

An approach for conjugation of 177 Lu- DOTA-SCN- Rituximab (BioSim) & its evaluation for radioimmunotherapy of relapsed & refractory B-cell non Hodgkins lymphoma patients


Parul Thakral1, Suhas Singla1, Madhav Prasad Yadav1, Atul Vashist2, Atul Sharma3, Santosh Kumar Gupta1, C. S. Bal1, Snehlata1, Arun Malhotra1 
1 Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India
2 Department of Biotechnology, All India Institute of Medical Sciences, New Delhi, India
3 Department of Medical Oncology, All India Institute of Medical Sciences, New Delhi, India

Correspondence Address:
Arun Malhotra
Professor & Head, Room No 4, Department of Nuclear Medicine & PET, All India Institute of Medical Sciences, Ansari Nagar, New Delhi 110 029
India

Background & objectives: The prerequisite of radioimmunotherapy is stable binding of a radionuclide to monoclonal antibodies, which are specific to the tumour-associated antigen. Most B-cell lymphomas express CD20 antigen on the surface of the tumour cells, making it a suitable target for therapeutic radioactive monoclonal antibodies. In the present study, the immunoconjugate of biosimilar Rituximab (Reditux™) and macrocyclic chelator, p-SCN-Bz-DOTA, was prepared and radiolabelled with Lutetium-177 followed by quality control procedures. Methods: Rituximab(BioSim) was desalted with sodium bicarbonate (0.1M, pH 9.0) and incubated with DOTA-SCN (1:50). The effectiveness of the conjugation was evaluated by determining the number of chelators per antibody molecule. This conjugate was radiolabelled with Lutetium-177 and purified using PD10 column. The quality control parameters like pH, clarity, radiochemical purity, in vitro stability and sterility were studied. Immunoreactivity of 177 Lu-DOTA-Rituximab (BioSim) was assessed using RAMOS cells. The radioimmunoconjugate (RIC) after stringent quality assurance was injected in three patients and the biodistribution profile was analysed. Results: An average of 4.25 ± 1.04 p-SCN-Bz-DOTA molecules could be randomly conjugated to a single molecule of Rituximab (BioSim).The radiochemical purity of the labelled antibody was > 95 per cent with preserved affinity for CD20 antigen. The final preparation was stable up to about 120 h when tested under different conditions. A favourable biodistribution profile was observed with liver showing the maximum uptake of the RIC. Interpretation & conclusions: A favourable radiochemical purity, stability and biodistribution of the radiolabelled immunoconjugate indicate that clinical trials for evaluation of toxicity and efficacy of 177 Lu-DOTA-antiCD20 antibody-Rituximab (BioSim) in patients of relapsed and refractory non Hodgkin«SQ»s lymphoma can be considered.


How to cite this article:
Thakral P, Singla S, Yadav MP, Vashist A, Sharma A, Gupta SK, Bal CS, Snehlata, Malhotra A. An approach for conjugation of 177 Lu- DOTA-SCN- Rituximab (BioSim) & its evaluation for radioimmunotherapy of relapsed & refractory B-cell non Hodgkins lymphoma patients.Indian J Med Res 2014;139:544-554


How to cite this URL:
Thakral P, Singla S, Yadav MP, Vashist A, Sharma A, Gupta SK, Bal CS, Snehlata, Malhotra A. An approach for conjugation of 177 Lu- DOTA-SCN- Rituximab (BioSim) & its evaluation for radioimmunotherapy of relapsed & refractory B-cell non Hodgkins lymphoma patients. Indian J Med Res [serial online] 2014 [cited 2020 Nov 28 ];139:544-554
Available from: https://www.ijmr.org.in/article.asp?issn=0971-5916;year=2014;volume=139;issue=4;spage=544;epage=554;aulast=Thakral;type=0