Stability Matters: Radiochemical Stability of Therapeutic Radiopharmaceutical ¹⁷⁷Lu-PSMA I&T.

Area of Science:

• Nuclear Medicine
• Radiopharmaceutical Chemistry
• Oncology

Background:

• Radiopharmaceutical quality control is crucial for patient safety in nuclear medicine.
• 177Lutetium (Lu) is an emerging therapeutic isotope for advanced cancers like mCRPC and NETs.
• Automated synthesis systems streamline radiopharmaceutical production.

Purpose of the Study:

• To evaluate the in vitro stability and radiochemical purity of 177Lu-PSMA I&T produced via automated synthesis.
• To determine the shelf-life of 177Lu-PSMA I&T for clinical use.

Main Methods:

• 35 batches of 177Lu-PSMA I&T were synthesized using an automated system.
• Product quality was assessed using HPLC and ITLC at 0, 24, and 48 hours post-synthesis.
• Radiochemical purity was the primary quality metric evaluated.

Main Results:

• The average radiochemical purity by ITLC-silica gel was consistently high, exceeding 99% (99.70% ± 0.05%).
• HPLC analysis also demonstrated excellent purity, averaging above 98% (98.60% ± 0.05%).
• These purity levels were maintained up to 48 hours post-labeling.

Conclusions:

• Automated synthesis of 177Lu-PSMA I&T yields a high-quality product.
• 177Lu-PSMA I&T exhibits excellent in vitro stability for at least 48 hours.
• This stability supports the clinical utility of 177Lu-PSMA I&T in managing mCRPC.