Benzinga | May 26, 2021 08:22AM EDT

Monopar Therapeutics, NorthStar Medical Report Filing Of Provisional Composition Of Matter Patent Titled 'Urokinase Plasminogen Activator Receptor-Targeted Radiopharmaceutical'

Monopar Therapeutics Inc. (NASDAQ:MNPR) and NorthStar Medical Radioisotopes, LLC, today announced the filing of a provisional composition of matter patent titled "Urokinase Plasminogen Activator Receptor-Targeted Radiopharmaceutical" covering a radiotherapeutic consisting of Monopar's proprietary antibody MNPR-101 bound to Actinium-225 (Ac-225) via the metal binding agent PCTA. This Radio-Immuno-Therapeutic (RIT) demonstrated a 98% radiochemical purity and has the potential to be a highly selective, potent treatment for a variety of cancers, severe COVID-19, and other diseases characterized by aberrant urokinase plasminogen activator receptor (uPAR) expression.

RITs are an emerging class of drugs formed by attaching a radioactive element to an antibody for the purpose of targeting and killing specific cells. Actinium is quickly becoming a premier radioisotope of choice for RITs; however, its full potential is presently constrained by its price and scarcity. On May 24, 2021, Monopar and NorthStar announced the filing of a provisional patent which may enable them to manufacture antibody-PCTA-Ac225 conjugates using less antibody and less Ac-225 starting material, and may also confer efficacy and safety advantages while also improving supply chain logistics.

"We are excited about working with Monopar to develop MNPR-101 as a radio-immuno-therapeutic, and advancing it further toward the clinic," said James Harvey, PhD, Chief Scientific Officer of NorthStar.

"The binding of Actinium-225 to PCTA-MNPR-101 with 98% yield is highly encouraging," said Andrew Mazar, PhD, Monopar's Chief Scientific Officer. "If issued, this composition of matter patent could significantly expand the MNPR-101 patent estate."