Perspective Therapeutics, Inc. ("Perspective" or the "Company") (NYSE AMERICAN: CATX), a radiopharmaceutical company that is pioneering advanced treatments for cancers throughout the body, today announced that the first patient was treated with [212Pb]PSV359 in a second cohort of the Company’s Phase 1/2a dose-finding trial to determine safety and preliminary anti-tumor activity of the radiopharmaceutical [212Pb]PSV359 in patients with solid tumors that express fibroblast activation protein alpha (FAP-α). Patients are being selected for [212Pb]PSV359 targeted alpha particle therapy by SPECT imaging with [203Pb]PSV359.
Patients in this cohort are receiving [212Pb]PSV359 at 5.0 mCi for up to four doses every eight weeks. The Safety Monitoring Committee (SMC) recommended evaluating [212Pb]PSV359 at a higher dose based on its review of two patients dosed with [212Pb]PSV359 at 2.5 mCi alone.
“Dosing the first patient in the second cohort marks an important step in advancing our evaluation of [212Pb]PSV359 for cancers expressing FAP-α,” said Markus Puhlmann, Chief Medical Officer of Perspective. “FAP-α is found in a wide range of epithelial malignancies, including pancreatic cancer, colorectal cancer, and many sarcomas. Because of its multi-factorial biologic effects within the tumor microenvironment, it contributes to disease progression and negatively affects treatment response. These characteristics highlight the broad potential of PSV359 across multiple solid tumors. This study is helping us determine the optimal dose and indications to move forward, either as a monotherapy or in future combination strategies.”
About PSV359
PSV359 was designed to target and deliver 212Pb to tumor sites expressing FAP-α, associated with multiple highly prevalent solid tumors, with patients in need of additional treatment options. The targeting moiety may also be radiolabeled with 203Pb or 68Ga (known as PSV377) to detect FAP-α expression in individual patients. Preclinical imaging and therapy as well as human imaging results suggest Perspective's proprietary targeting ligand has improved levels of target engagement and uptake in tumors, as well as reduced retention in healthy tissues, which may result in a desirable therapeutic index.
Perspective is conducting a multi-center, open-label, dose-finding and dose-expansion study (clinicaltrials.gov identifier NCT06710756) of [212Pb]PSV359 in patients with advanced solid tumors that express FAP-α as determined by imaging with [203Pb]PSV359. The primary objective of the dose finding phase of the study is to assess the safety and tolerability of various doses of [212Pb]PSV359 in order to determine the recommended Phase 2 dose to be used in the expansion phase of the study, where anti-tumor activities may be an additional primary outcome measure.
About FAP-α
FAP-α is a protein abundantly expressed on the surface of cancer-associated fibroblasts (CAFs) in the stroma, a part of the tumor microenvironment (TME) in the majority of epithelial cancers. In addition to expression on CAFs, FAP-α is expressed on certain cancer cells themselves, including sarcomas and mesotheliomas.1,2,3,4 Higher FAP-α expression has been found to be associated with poor prognosis in a number of solid tumors such as colorectal cancer, pancreatic cancer, stomach cancer, mesothelioma, head and neck cancer, esophageal cancer, and ovarian cancer.5,6,7,8,9 Expression of FAP-α in healthy tissues is usually low.3,4
About Perspective Therapeutics, Inc.
Perspective Therapeutics, Inc. is a radiopharmaceutical development company pioneering advanced treatments for cancers throughout the body. The Company has proprietary technology that utilizes the alpha-emitting isotope 212Pb to deliver powerful radiation specifically to cancer cells via specialized targeting moieties. The Company is also developing complementary imaging diagnostics that incorporate the same targeting moieties, which provides the opportunity to personalize treatment and optimize patient outcomes. This "theranostic" approach enables the ability to see the specific tumor and then treat it to potentially improve efficacy and minimize toxicity.
The Company's neuroendocrine tumor (VMT-α-NET), melanoma (VMT01), and solid tumor (PSV359) programs are in Phase 1/2a imaging and therapy trials in the U.S. The Company is growing its regional network of drug product candidate finishing facilities, enabled by its proprietary 212Pb generator, to deliver patient-ready product candidates for clinical trials and commercial operations.
For more information, please visit the Company's website at www.perspectivetherapeutics.com.