Perspective Therapeutics Introduces “Pre-Targeting” Theranostic Technology Platform

• Signs a World-Wide Exclusive License with Stony Brook University for a Novel Platform that can Enhance Radionuclide Targeting
  
  
• Receives up to $2.4M NIH Grant to Develop Differentiated Antibody-based Radiopharmaceutical Approach
  
  

SEATTLE, Feb. 01, 2024 (GLOBE NEWSWIRE) --  -- Perspective Therapeutics, Inc.  (“Perspective” or “the Company”) (NYSE AMERICAN: CATX), a radiopharmaceutical company that is pioneering advanced treatment applications for cancers throughout the body, today announced that it has executed an exclusive license agreement with Stony Brook University for the rights to its Cuburbit[7]uril-admantane (CB7-Adma) pre-targeting platform and was awarded the Phase I tranche of a 2.5-year, Fastrack Small Business Innovation Research grant (Phase I $400 thousand; total $2.4 million) from the National Institutes of Health (NIH) National Cancer Institute in support of Perspective’s CB7-Adma host-guest pre-targeting program for the diagnosis and treatment of cancer.

Pre-targeting using the CB7-Adma platform involves two-steps. First, an antibody that binds with high specificity to a cancer-specific protein is administered via intravenous injection. This antibody is chemically modified to include the CB7 chemical entity and accumulates over time at the tumor site. Then, a radionuclide held tightly by Perspective’s proprietary chelator attached to an Adma group is administered. The Adma group binds to the CB7 group that was previously attached to the cancerous cells with remarkable specificity, delivering radiation dose selectively to the tumor sites.

Central to this innovation is CB7-Adma (host-guest) complex formation, driving the interaction between the antibody and radioligand. The chosen host-guest pair, CB7-Adma, demonstrates promising in vivo stability, modularity, and low immunogenicity. The platform's potential was validated through in vivo profiling of ligands, employing a CB7-modified carcinoembryonic antigen (CEA) targeting antibody.

Figure 1. Illustration of the 2-step CB7-Adma pre-targeting approach. (1) a macromolecule that has been chemically modified to include the CB7 handle is administered and allowed to bind to the tumor. (2) The radioligand with fast clearance properties that carries the radionuclide, and the Adma chemical group is administered. The Adma guest ligand binds to the tumor rapidly and unbound radioligand clears the body quickly, thereby optimizing delivery of radioactivity to the tumor, with little interaction with healthy tissue and organs. (Jallinoja et al., J Nucl Med 2023; 64:1203–1209)

“By embracing a strategy that leverages the precision of monoclonal antibodies and the versatility of small molecules, Perspective has the opportunity to expand the therapeutic options available to patients receiving radiation therapy,” said Thijs Spoor, Chief Executive Officer at Perspective Therapeutics.

Michael K Schultz, Ph.D., Perspective’s Chief Science Officer added, “We are excited about the potential of this technology because it opens up numerous additional cancer-specific targets and is ideal for alpha-particle therapy using ²¹²Pb.”

The exclusive license with Stony Brook University covers the global intellectual property rights for the CB7-Adma pre-targeting platform. The research conducted at Stony Brook University refines the understanding of the potential of the proprietary CB7-Adma pre-targeting platform for image-guided radionuclide therapy for oncology. The technology was first described by Stony Brook University researchers, Jacob L. Houghton, Ph.D. and Vilma I.J. Jallinoja, Ph.D., in the article, “Pretargeting with Cucurbituril–Adamantane Host–Guest Pair in Xenograft Models,” published in The Journal of Nuclear Medicine. A recent presentation by the Stony Brook team at the World Molecular Imaging Congress 2023, “Cucurbit[7]uril-adamantane host:guest pretargeting with ²⁰³Pb-labeled radioligands in xenograft models,” demonstrated the feasibility of this approach in combination with Perspective’s lead-specific chelator (“PSC”).

“This innovative radioligand treatment strategy circumvents the potential toxic side effects typically associated with directly radiolabeled monoclonal antibodies by employing a two-step targeting strategy utilizing the specificity of monoclonal antibodies with the safety and efficacy of radioligands,” said Jacob Houghton, Ph.D., Assistant Professor, Radiology at Stony Brook University. “Our current efforts will focus on optimizing the radioligands in combination with ²¹²Pb for alpha-TRT, using Perspective’s PSC chelator, which has the potential to further reduce off-target radiation toxicity by tightly binding not only the ²¹²Pb, but also the ²¹²Bi progeny in the ²¹²Pb decay series.”

About Perspective Therapeutics, Inc.
Perspective Therapeutics, Inc., is a radiopharmaceutical development company that is pioneering advanced treatment applications for cancers throughout the body. The Company has a proprietary technology that utilizes the alpha emitting isotope ²¹²Pb to deliver powerful radiation specifically to cancer cells via specialized targeting peptides. The Company is also developing complementary imaging diagnostics that incorporate the same targeting peptides which provide 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 associated with many other types of cancer treatments.

The Company’s melanoma (VMT01) and neuroendocrine tumor (VMT-α-NET) programs have entered Phase 1/2a imaging and therapy trials for the treatment of metastatic melanoma and neuroendocrine tumors at several leading academic institutions. The Company has also developed a proprietary ²¹²Pb generator to secure key isotopes for clinical trial and commercial operations.

For more information, please visit the Company’s website at www.perspectivetherapeutics.com.

Safe Harbor Statement

This press release contains forward-looking statements within the meaning of the United States Private Securities Litigation Reform Act of 1995. Statements in this press release that are not statements of historical fact are forward-looking statements. Words such as "may," "will," "should," "expect," "plan," "anticipate," "could," "intend," "target," "project," "estimate," "believe," "predict," "potential" or "continue" or the negative of these terms or other similar expressions are intended to identify forward-looking statements, though not all forward-looking statements contain these identifying words. Forward-looking statements in this press release include statements concerning, among other things: the Company’s ability to develop a differentiated antibody-based radiopharmaceutical approach; the success of the Company’s CB7-Adma host-guest pre-targeting program for the diagnosis and treatment of cancer; the ability of the chosen host-guest pair, CB7-Adma, to demonstrate promising in vivo stability, modularity, and low immunogenicity; the platform's potential for continued validation through in vivo profiling of ligands, employing a CB7-modified carcinoembryonic antigen (CEA) targeting antibody; the Company’s belief that its ability to embrace a strategy that leverages the precision of monoclonal antibodies and the versatility of small molecules, poises the Company to redefine the landscape of radiation therapy; the Company’s ability to deliver safe and effective radiotherapies to patients; the Company’s belief that the support of the National Institutes of Health grant will undoubtedly further enable the Company to realize its ability to deliver safe and effective radiotherapies to patients, by adapting the CB7-Adma platform to the Company’s growing number of targeted alpha therapies; the Company’s belief that the CB7-Adma platform has the potential to open up numerous additional cancer-specific targets and is ideal for alpha-particle therapy using ²¹²Pb; the Company’s belief that the research conducted at Stony Brook University refines the understanding of the potential of the proprietary CB7-Adma pre-targeting platform for image-guided radionuclide therapy for oncology; the Company’s belief that the innovative CB7-Adma platform and radioligand treatment strategy circumvents the potential toxic side effects typically associated with directly radiolabeled monoclonal antibodies, by employing a two-step targeting strategy utilizing the specificity of monoclonal antibodies with the safety and efficacy of radioligands; the Company’s ability to focus current efforts on optimizing the radioligands in combination with ²¹²Pb for alpha-TRT, using the Company’s PSC chelator; the Company’s belief that focusing on optimizing the radioligands in combination with ²¹²Pb for alpha-TRT, using the Company’s PSC chelator has the potential to further reduce off-target radiation toxicity by tightly binding not only the ²¹²Pb, but also the ²¹²Bi progeny in the ²¹²Pb decay series; the Company's prediction that complementary imaging diagnostics that incorporate certain targeting peptides provide the opportunity to personalize treatment and optimize patient outcomes; the Company's expectation that its "theranostic" approach enables the ability to see specific tumors and then treat it to potentially improve efficacy and minimize toxicity associated with many other types of cancer treatments; the Company's clinical development plans and the expected timing thereof; the potential functionality, capabilities, and benefits of the Company's product candidates and the potential application of these product candidates for other disease indications; the Company's expectations, beliefs, intentions, and strategies regarding the future; and other statements that are not historical fact.

The Company may not actually achieve the plans, intentions or expectations disclosed in the forward-looking statements and you should not place undue reliance on the forward-looking statements. These forward-looking statements involve risks and uncertainties that could cause the Company's actual results to differ materially from the results described in or implied by the forward-looking statements, including, without limitation: the Company's ability to continue as a going concern, the potential that regulatory authorities may not grant or may delay approval for the Company's product candidates; uncertainties and delays relating to the design, enrollment, completion, and results of clinical trials; unanticipated costs and expenses; early clinical trials may not be indicative of the results in later clinical trials; clinical trial results may not support regulatory approval or further development in a specified indication or at all; actions or advice of regulatory authorities may affect the design, initiation, timing, continuation and/or progress of clinical trials or result in the need for additional clinical trials; the Company's ability to obtain and maintain regulatory approval for the Company's product candidates; delays, interruptions or failures in the manufacture and supply of the Company's product candidates; the size and growth potential of the markets for the Company's product candidates, and the Company's ability to service those markets; the Company's cash and cash equivalents may not be sufficient to support its operating plan for as long as anticipated; the Company's expectations, projections and estimates regarding expenses, future revenue, capital requirements, and the availability of and the need for additional financing; the Company's ability to obtain additional funding to support its clinical development programs; the availability or potential availability of alternative products or treatments for conditions targeted by the Company that could affect the availability or commercial potential of its product candidates; the ability of the Company to manage growth and successfully integrate its businesses; the Company's ability to maintain its key employees; whether there is sufficient training and use of the Company's products and product candidates; the market acceptance and recognition of the Company's products and product candidates; the Company's ability to maintain and enforce its intellectual property rights; the Company's ability to maintain its therapeutic isotope supply agreement with the Department of Energy; the Company's ability to continue to comply with the procedures and regulatory requirements mandated by the FDA for additional trials, Phase 1 and 2 approvals, FDA Fast Track approvals, and 510(k) approval and reimbursement codes; and any changes in applicable laws and regulations. Other factors that may cause the Company's actual results to differ materially from those expressed or implied in the forward-looking statements in this press release are described under the heading "Risk Factors" in the Company's most recent Transition Report on Form 10-KT and the Company's most recent Quarterly Report on Form 10-Q, each filed with the Securities and Exchange Commission (the "SEC"), in the Company's other filings with the SEC, and in the Company's future reports to be filed with the SEC and available at www.sec.gov. Forward-looking statements contained in this news release are made as of this date. Unless required to do so by law, we undertake no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise.