Development of single vial kits for preparation of (68)Ga-labelled peptides for PET imaging of neuroendocrine tumours.
OBJECTIVE
The present work was aimed at the formulation and evaluation of freeze-dried kits of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA)-peptides for the preparation of (68)Ga-labelled peptides for PET imaging of neuroendocrine tumours. The (68)GaCl3 was obtained from the locally produced nanoceria-PAN, composite-sorbent-based (68)Ge/(68)Ga generator.


METHODS
Single vial kits of somatostatin analogues DOTA-[Tyr(3)]-octreotide (DOTA-TOC), DOTA-[NaI(3)]-octreotide (DOTA-NOC) and DOTA-Tyr(3)-Thre(8)-octreotide (DOTA-TATE) were formulated. Optimization of radiolabelling with (68)Ga from the in-house generator, characterization, long term evaluation of stability of kits and bioevaluation studies in animals was carried out.


RESULTS
DOTA-TOC, DOTA-NOC and DOTA-TATE kits could be successfully formulated. Consistently high radiochemical yields (>95 %) were obtained on radiolabelling with (68)Ga. The radiolabelled peptides exhibited excellent in vitro stability. Biodistribution studies in normal non-tumour bearing Swiss mice revealed fast clearance of activity via renal route as reported for the respective peptides.


CONCLUSIONS
Availability of ready to use DOTA-peptide kits in conjunction with (68)Ge/(68)Ga generators would pave way for the establishment of (68)Ga radiopharmacy, a long-felt need of the nuclear medicine community.
Isotope Applications and Radiopharmaceuticals Division, Bhabha Atomic Research Centre (BARC), Mumbai, 400085, India.
Archana
A
Mukherjee
Usha
U
Pandey
Rubel
R
Chakravarty
Haladhar Dev
HD
Sarma
Ashutosh
A
Dash
D000818:Animals; D002563:Cerium; D002626:Chemistry, Pharmaceutical; D002851:Chromatography, High Pressure Liquid; D005612:Freeze Drying; D005710:Gallium Radioisotopes; D051379:Mice; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging*; D015282:Octreotide / Q000031:analogs & derivatives; D009942:Organometallic Compounds; D010455:Peptides; D049268:Positron-Emission Tomography / Q000379:methods*; D011933:Reagent Kits, Diagnostic; D014018:Tissue Distribution
C504894:68Ga-DOTANOC; C499142:Ga(III)-DOTATOC; D005710:Gallium Radioisotopes; D009942:Organometallic Compounds; D010455:Peptides; D011933:Reagent Kits, Diagnostic; D002563:Cerium; C030583:ceric oxide; C513399:gallium Ga 68 dotatate; D015282:Octreotide