IP Library › Granted Patent US 12,502,441
Granted Patent B2
US 12,502,441 · App. 19/204,235 · Granted Dec 23, 2025

Radiopharmaceutical compositions for low toxicity actinium in targeted radionuclide therapy

Inventors: Jarno Jalomäki (Helsinki, FI); Salla Seppänen (Helsinki, FI); Riku Parviainen (Helsinki, FI)
Assignee: Curium US LLC
A61K51/088A61K9/08A61K47/02A61K47/10A61K47/22
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Quick Facts
Patent No.
US 12,502,441
App. No.
19/204,235
Granted
Dec 23, 2025
Kind
B2
Abstract

The present disclosure provides a high-energy, low toxicity radiopharmaceutical composition comprising actinium that performs as an anti-tumor agent for targeted radionuclide therapy and has improved shelf-life stability. Specifically, the radiopharmaceutical composition may include 225 Ac-PSMA I&T, sodium ascorbate, and optionally hydrochloric acid. The radiopharmaceutical composition may be suitable for administration to a patient in need thereof, such as for the purpose of treating prostate cancer.

Claims (16)

1 . A radiopharmaceutical composition comprising:

225 Ac-PSMA I&T in an amount that provides a radioactivity concentration of about 250 kBq/mL to about 1100 kBq/mL; and

sodium ascorbate in an amount of about of about 0.1 mg/mL to about 100 mg/mL; and,

optionally hydrochloric acid;

wherein the composition has a radiochemical purity of about 90% to about 100%; and

wherein the composition has a radiochemical stability of greater than 72-hours from production when stored at about 5° C. to about 40° C.

2 . The radiopharmaceutical composition of claim 1 , further comprising ethanol in an amount of about 1% to about 20% (v/v).

3 . The radiopharmaceutical composition of claim 1 , wherein pH of the composition is from about 5.5 to about 7.5.

4 . The radiopharmaceutical composition of claim 1 , wherein the composition has no metal scavengers.

5 . The radiopharmaceutical composition of claim 1 , wherein the sodium ascorbate is present at 11.3 mg/mL±15%.

6 . The radiopharmaceutical composition of claim 1 , wherein the composition has a radiochemical stability of greater than 120-hours at about 5° C. to about 40° C.

7 . The radiopharmaceutical composition of claim 1 , wherein the radioactivity concentration is about 500 kBq/mL to about 600 kBq/mL.

8 . The radiopharmaceutical composition of claim 1 , wherein the molar ratio of hydrochloric acid to sodium ascorbate is between 1:1 to 1:500.

9 . The radiopharmaceutical composition of claim 1 , wherein the molar ratio of the PSMA I&T to 225 Ac is from 1.000:1.0 to 5.000:1.0.

10 . The radiopharmaceutical composition of claim 1 , wherein the composition has a relative biological effectiveness (RBE) of ≥4.0 for 225 Ac compared to 177 Lu.

11 . The radiopharmaceutical composition of claim 1 , wherein the composition has a Fe, Cu, Zn, and Pb metal content of ≤0.05 μg/GBq below the detectable limit.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 13, 2025
From: JALOMÄKI, JARNO; SEPPÄNEN, SALLA; PARVIAINEN, RIKU
To: CURIUM US LLC
Reel/Frame 072553/0129 →
Continuity (5)
Provisional Application 63753208 · Feb 3, 2025
Provisional Application 63691082 · Sep 5, 2024
Provisional Application 63645572 · May 10, 2024
Provisional Application 63644943 · May 9, 2024
Related Publication 20250345470A1 · Nov 13, 2025
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