Patent ID: 11957760
Assignee: ELUCIDA ONCOLOGY, INC.
Field: Pharmaceuticals (Chemistry)
Classification: CPC A | IPC A

Claim 3:
4. A nanoparticle-drug conjugate (NDC) comprising:
(a) a silica nanoparticle;
(b) polyethylene glycol (PEG) that is covalently bonded to the surface of the silica nanoparticle;
(c) a targeting ligand comprising folic acid, wherein the targeting ligand is attached to the silica nanoparticle through a first spacer group; and
(d) a linker-payload conjugate that is attached to the silica nanoparticle through a second spacer group, wherein the payload is exatecan, the linker is a protease-cleavable linker, the exatecan is released upon cleavage of the linker, and wherein the linker-payload conjugate comprises a structure of Formula (I):, , or a salt thereof,, wherein,
 denotes a point of attachment to the second spacer group;
A is Val-Lys;
Payload comprises a residue of the exatecan;
Z is an —NH— group of the exatecan;
R1, R2, R3, R4, and R5 in each occurrence is independently hydrogen;
X is absent;
Y is, wherein the carbonyl in, is bonded to Z;
X1, X2, X3, and X4 are each independently —CH—; and
n is 1.