{"entity": "publication", "iuid": "d51c553d17cd4f96bfb300dc715cb1f3", "timestamp": "2026-08-22T07:47:34.769Z", "links": {"self": {"href": "https://publications-affiliated.scilifelab.se/publication/d51c553d17cd4f96bfb300dc715cb1f3.json"}, "display": {"href": "https://publications-affiliated.scilifelab.se/publication/d51c553d17cd4f96bfb300dc715cb1f3"}}, "title": "Phase I Trial of [99mTc]Tc-maSSS-PEG2-RM26, a Bombesin Analogue Antagonistic to Gastrin-Releasing Peptide Receptors (GRPRs), for SPECT Imaging of GRPR Expression in Malignant Tumors.", "authors": [{"family": "Chernov", "given": "Vladimir", "initials": "V"}, {"family": "Rybina", "given": "Anastasiya", "initials": "A"}, {"family": "Zelchan", "given": "Roman", "initials": "R"}, {"family": "Medvedeva", "given": "Anna", "initials": "A"}, {"family": "Bragina", "given": "Olga", "initials": "O"}, {"family": "Lushnikova", "given": "Nadejda", "initials": "N"}, {"family": "Doroshenko", "given": "Artem", "initials": "A"}, {"family": "Usynin", "given": "Evgeniy", "initials": "E"}, {"family": "Tashireva", "given": "Liubov", "initials": "L", "orcid": "0000-0003-2061-8417", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/e462c38bfd8846588156097b5602341a.json"}}, {"family": "Vtorushin", "given": "Sergey", "initials": "S"}, {"family": "Abouzayed", "given": "Ayman", "initials": "A"}, {"family": "Rinne", "given": "Sara S", "initials": "SS", "orcid": "0000-0003-2141-3982", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/3aea3edd98b441c98bb527b1e0c911f5.json"}}, {"family": "S\u00f6rensen", "given": "Jens", "initials": "J"}, {"family": "Tolmachev", "given": "Vladimir", "initials": "V", "orcid": "0000-0002-6122-1734", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/896ae9fae8b74251afe11b4354c62794.json"}}, {"family": "Orlova", "given": "Anna", "initials": "A", "orcid": "0000-0001-6120-2683", "researcher": {"href": "https://publications-affiliated.scilifelab.se/researcher/1c374f429702489494c05f84f298b4b7.json"}}], "type": "journal article", "published": "2023-03-07", "journal": {"title": "Cancers (Basel)", "issn": "2072-6694", "volume": "15", "issue": "6", "issn-l": "2072-6694"}, "abstract": "The gastrin-releasing peptide receptor (GRPR) is overexpressed in prostate cancer (PCa) and in hormone-driven breast cancer (BCa). The aim of this phase I clinical trial was to evaluate safety, biodistribution, and dosimetry after the administration of the recently developed GRPR-targeting antagonistic bombesin analogue [99mTc]Tc-maSSS-PEG2-RM26 in PCa and BCa patients. Planar and whole-body SPECT/CT imaging was performed in six PCa patients and seven BCa patients 2, 4, 6, and 24 h post the intravenous administration of 40 \u00b5g of [99mTc]Tc-maSSS-PEG2-RM26 (600-700 MBq). No adverse events or pathological changes were observed. The rapid blood clearance of [99mTc]Tc-maSSS-PEG2-RM26 was observed with predominantly hepatobiliary excretion. The effective doses were 0.0053 \u00b1 0.0007 for male patients and 0.008 \u00b1 0.003 mSv/MBq for female patients. The accumulation of [99mTc]Tc-maSSS-PEG2-RM26 in tumors was observed in four out of six PCa and in seven out of seven BCa patients. In four BCa patients, a high uptake of the agent into the axillary lymph nodes was detected. Immunohistochemistry revealed positive GRPR expression in 60% of primary PCa, 71.4% of BCa tumors, and 50% of examined BCa lymph nodes. In conclusion, a single administration of [99mTc]Tc-maSSS-PEG2-RM26 was safe and well tolerated. [99mTc]Tc-maSSS-PEG2-RM26 SPECT may be useful for tumor detection in PCa and BCa patients, pending further studies.", "doi": "10.3390/cancers15061631", "pmid": "36980517", "labels": [], "xrefs": [{"db": "pmc", "key": "PMC10046460"}, {"db": "pii", "key": "cancers15061631"}], "notes": [], "created": "2026-08-21T13:01:52.506Z", "modified": "2026-08-21T13:01:52.564Z"}