Nihon Medi-physics Company, Limited

Kagoshima University

Chiba University

Sumitomo Pharma Co., Ltd.

Yoshinari Shoyama

Yuji Ito

Yuki Okumura

Norihito Nakata

Yoshifumi Maya

Takako Onishi

Akio Hayashi

Hiroyuki Suzuki

Yasushi Arano

Mitsuhiro Matono

Yu Ogawa

Nobuya Kobashi

Tomoya Uehara

Tadashi Hatano

Yasushi Ochiai

Takayuki Murakami

Shota Komoto

The present invention relates to an IgG-binding peptide comprising a ligand capable of binding to a radioactive metal nuclide, an IgG-binding peptide labeled with a radioactive metal nuclide, a conjugate of the IgG-binding peptide and IgG, and a radionuclide imaging agent or a diagnostic agent for cancer comprising the IgG-binding peptide or the conjugate, etc.

Site-specific radioisotope-labeled antibody using IgG-binding peptide

Described is a labeling technique which can facilitate the metabolism in the liver after administration to patients without the reduction in the antibody function, thereby reducing accumulation of radionuclides in an organ such as the liver, and a modified antibody containing an IgG antibody and an IgG-binding peptide bound to the IgG antibody. The IgG-binding peptide has an amino acid sequence consisting of 13 to 17 amino acid residues, such as GPDCAYH(Xaa1)GELVWCTFH (SEQ ID NO: 2) wherein Xaa1 represents a lysine residue, a cysteine residue, an aspartic acid residue, a glutamic acid residue, 2-aminosuberic acid, or diaminopropionic acid, and a compound represented by the following formula (II-1) is linked at a position of the lysine residue via a modification linker to the N terminus of the IgG-binding peptide.

Modified antibody and radioactive metal-labelled antibody

The RI-labeled anti-MUC5AC humanized antibody of the present invention is a conjugate of a chelating agent chelated with a radionuclide and an antibody (the radionuclide is a metal nuclide that emits &#x3b1; particle or positron, and the antibody is a humanized antibody specifically binding to MUC5AC), and is superior in specificity for MUC5AC and accumulation in tumor. Therefore, it is extremely useful for the treatment and/or diagnosis of diseases in which MUC5AC is overexpressed, particularly cancer.

Ri-labeled humanized antibody

A compound represented by the following formula (1), or a salt thereof: wherein Ris a radioactive halogen substituent, 0 to 2 of A, A, Aand Arepresent N, and the rest represent &#x2014;(CH)&#x2014; is effective as a diagnostic imaging probe targeting amyloid. A diagnostic agent for Alzheimer's disease contains a compound represented by the above formula (1) or a salt thereof. After administration to a patient, the compound and the diagnostic agent for Alzheimer's disease transfer into the patient's brain, and indicate good accumulation on amyloid deposited in the brain.

Compound with amyloid affinity

A compound that is effective as a diagnostic imaging probe that targets amyloid including is represented by the following formula (1), or salt thereof: wherein Ris a radioactive halogen substituent, Aand Aindependently represent CH or N. A diagnostic agent for Alzheimer's disease includes the compound represented by the above formula or a salt thereof. The above compound and the above diagnostic agent for Alzheimer's disease transfer into brain after administration, and indicate good accumulation on amyloid deposited in the brain.

Compound having affinity for amyloid

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Sodegaura, Japan

Yoshinari Shoyama