• Viewpoint advancing new, proprietary class of personalized ²¹² Pb-based alpha-particle radiopharmaceuticals to transform the treatment landscape of radiotherapies for cancer
• Positive preclinical data have demonstrated that a single dose of [²¹² Pb]VMT01 has significantly arrested melanoma tumor growth and extended survival
• The combination of [²¹² Pb]VMT01 and immune checkpoint inhibitors produced a 43% complete and durable response rate in this preclinical study
• Company currently evaluating VMT01 in Phase 1 imaging study to be followed by Phase 1/2a therapy study for the treatment of metastatic melanoma being conducted at Mayo Clinic

CORALVILLE, IA / ACCESSWIRE / September 22, 2021 / Viewpoint Molecular Targeting, Inc. ('Viewpoint' or the 'Company'), a radiopharmaceutical company developing precision lead-212-based α-particle oncology therapeutics and complementary diagnostic imaging agents, today announced the publication of VMT01 preclinical data in an article titled, Targeted Alpha-Particle Radiotherapy and Immune Checkpoint Inhibitors Induces Cooperative Inhibition on Tumor Growth of Malignant Melanoma¹ in the peer-reviewed journal Cancers.

VMT01 is Viewpoint's specialized peptide designed to target the melanocortin 1 receptor (MC1R) on tumor cells. The results from preclinical studies indicate that MC1R-targeted therapies, such as peptide receptor radionuclide therapies (PRRT), are a promising alternative to current therapies for metastatic melanoma. In the published preclinical data, the ²¹² Pb radiolabeled peptide [²¹² Pb]VMT01 targeting MC1R was used to deliver α-particle radiation to melanoma cells. Robust anti-tumor specific cooperation between [²¹² Pb]VMT01 and systemic immune checkpoint inhibitor (ICI) immunotherapy was observed in preclinical melanoma models. This cooperation relies on the combination of the intact adaptive immunity and the immunogenicity caused by [²¹² Pb]VMT01.

'We are very pleased with the results of this preclinical study and are honored with the acceptance of this manuscript for publication in Cancers. We continue to be encouraged by the potential of VMT01 to significantly enhance responses to currently available immunotherapies for the treatment of metastatic melanoma,' commented Michael K. Schultz, PhD, Chief Science Officer of Viewpoint. 'Our data suggest that our targeted alpha-particle therapies have the potential to significantly enhance responses to currently available immunotherapies for the treatment of metastatic melanoma. We look forward to providing updates on our imaging study of VMT01 and the rest of our pipeline leveraging our proprietary ²¹² Pb alpha-particle radiotherapies and complementary ²⁰³ Pb diagnostic imaging agents.'

Key findings of the publication are summarized below:

• The combination of [²¹² Pb]VMT01 and immune checkpoint inhibitor therapy resulted in 43% complete and durable response rate in the syngeneic mouse model.
• Further in vivo assays and rechallenge studies (in which naïve tumor cells were reintroduced to treated mice after a complete response) suggested a tumor specific T-cell mediated immune response.
• Mice who demonstrated complete response to the combination of VMT01 and immune checkpoint inhibitors demonstrated resistance to the reintroduction of tumor cells, with either no growth or much slower tumor growth observed in these animals compared with control cohorts.
• The results of this study suggest that targeted radionuclide therapy (TRT) such as [²¹² Pb]VMT01 is emerging as an effective approach to systemically deliver α-particle radiation that can induce anti-tumor immunity and enhance the efficacy of immunotherapies in a cooperative, potentially synergistic manner.
• Data demonstrated that [²¹² Pb]VMT01 induced immunogenic cell death, tumor infiltrating lymphocytes, and sensitized immunotolerant melanoma tumors to ICI treatments (i.e., tumors were unresponsive to ICI therapy alone).

Viewpoint's VMT01 program is intended to address an unmet clinical need with the use of a new imaging agent to guide Viewpoint's radiopharmaceutical therapy against metastatic melanoma. This image-guided approach is often referred to as 'theranostics.' Using information guided by the low-risk medical imaging scan, a treatment plan utilizing the VMT01 ligand is designed to deliver the power of alpha-particle radiation specifically to melanoma tumors, while minimizing risk to unaffected organs and tissues. VMT01 represents a unique way to treat metastatic melanoma that has been vetted as scientifically sound by rigorous peer review and has the potential to be transformative for melanoma patients.

VMT01 is currently being evaluated in a Phase 1 imaging study being conducted at the Mayo Clinic. Provisional results for the VMT01 imaging study are targeted for Q4 2021. Following the results of the imaging trial, the Company plans to initiate a Phase 1/2a therapy study of VMT01 for the treatment of metastatic melanoma.

About Viewpoint

Viewpoint Molecular Targeting is a radiopharmaceutical company developing precision oncology therapeutics and complementary diagnostic imaging agents. The Company's proprietary technology utilizes lead-212 to deliver powerful alpha radiation specifically to cancer cells via specialized targeting peptides. Viewpoint 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 are entering Phase 1 imaging studies, to be followed by Phase 1/2a therapy trials for the treatment of metastatic melanoma and neuroendocrine tumors at two leading academic institutions. The Company has also developed a proprietary lead-212 generator to secure isotope supply for clinical trial and commercial operations. For more information, please visit the Company's website viewpointmt.com.

​ Investor Inquiries:

Jenene Thomas
Chief Executive Officer
JTC Team, LLC
T: 833.475.8247
viewpoint@jtcir.com

SOURCE: Viewpoint Molecular Targeting, Inc.