Patent ID: 11866472
Assignee: DAIICHI SANKYO COMPANY, LIMITED
Field: Pharmaceuticals (Chemistry)
Classification: CPC C  A | IPC A  C

Claim 17:
18. A method for identifying a therapeutic drug or a prophylactic drug for retinitis pigmentosa, hereditary diseases involving photoreceptor cell degeneration, and/or diseases associated with PDE6 protein dysfunction, comprising the following steps 1 to 3:
[step 1] incubating a HTRA1 protease and a substrate in the presence and absence of a test substance, which is a SPINK2 mutant peptide comprising the amino acid sequence shown in SEQ ID NO: 30;
[step 2] detecting HTRA1 protease activity in the presence and absence of the test substance; and
[step 3] determining the test substance to be positive when the HTRA1 protease activity in the presence of the test substance is lower than the HTRA1 protease activity in the absence of the test substance.