JAPAN - PeptiDream Inc., a public Kanagawa, Japan-based biopharmaceutical company (President and CEO: Patrick C. Reid, hereinafter 'PeptiDream') (Tokyo: 4587) today announced that strategic partner RayzeBio, Inc., ('RayzeBio'), has completed an initial public offering ('IPO'), listing its shares on the Nasdaq Global Market ('Nasdaq') under the ticker 'RYZB' on September 15, 2023 (ET).
PeptiDream and RayzeBio have an ongoing multi-program collaboration, initiated in August 2020, to screen and identify novel macrocyclic peptide binders against tumor antigens for the targeted delivery of radioisotopes (referred to as macrocyclic peptideradioisotope ('RI') conjugates). The companies announced the nomination of their first clinical candidate in December 2022 (program target undisclosed), and the nomination of their second clinical candidate (against glypican 3 ('GPC3') for the treatment of liver cancer (Hepatocellular Carcinoma 'HCC')) in March 2023. Under the terms of the license and research collaboration agreement, PeptiDream retains the option right to develop and commercialize any such programs arising from the collaboration (both therapeutic and diagnostic peptide-RI-conjugates) in Japan, and additionally, is eligible to receive certain development and commercial sales milestones, as well as royalties on worldwide (ex-Japan) net sales in the mid to high single-digit percentage range.
Liver cancer is the sixth most common cause of cancer death in United States, with an estimated 29,380 deaths per year. The five-year survival rate for all liver cancer patients is approximately 20% and the survival rate of patients with advanced stage liver cancer is significantly lower. GPC3 is an oncofetal protein that is overexpressed in up to 75% of hepatocellular tumors, with minimal to no expression in normal tissues. RYZ801, the therapeutic development candidate, is a novel proprietary peptide which targets GPC3 for delivery of Ac-225 for the treatment of hepatocellular carcinoma 'HCC'. In preclinical studies of HCC xenograft models, the GPC3 binding peptide showed specific tumor uptake, and significant tumor growth inhibition including regression with single doses delivering Ac-225 or Lu-177. RYZ811, is a paired diagnostic imaging agent with the same peptide binder and chelator as RYZ801 but with Ga-68 as the radioisotope. As a diagnostic imaging agent, RYZ811 is designed to enable us to screen and identify patients, both in clinical trials and commercially, who have GPC3 expressing HCC tumors that are most likely to have a favorable clinical response from treatment with RYZ801. As of August 1, 2023, several clinical sites outside of the United States have imaged a total of 47 HCC patients using RYZ811, with approximately 90% showing uptake into HCC tumors. No patients had experienced any SAE. RYZ801 and RYZ811 are currently undergoing IND enabling September 19, 2023 PeptiDream Inc https://www.peptidream.com/en/ (Securities Code: 4587 TSE Prime Market) studies, with the plan to file INDs in the first half of 2024, followed by Phase 1 clinical trial for both RYZ801 and RYZ811 in patients with HCC.
At the time of the IPO, PeptiDream held 2,326,579 shares of RayzeBio, equating to a 5.5% stake in RayzeBio. PeptiDream sold 1,163,000 shares of RayzeBio in the IPO, yielding $20,934,000 USD (approximately 3 billion JPY (1USD = 147JPY)). PeptiDream retains 1,163,579 shares in RayzeBio. PeptiDream intends to use a portion of the proceeds of the sale to fund the development of RYZ801 and RYZ811 in Japan. 'We couldn't be happier for the entire RayzeBio team for their very successful IPO and listing on Nasdaq. We are also extremely excited with the recent human imaging data announced by RayzeBio of our GPC3-targeting peptide-RI conjugates, to which RayzeBio refers to as RYZ801 and RYZ811, showing clear tumor targeting and uptake in liver cancer patients. The companies intend to file INDs for both products (therapeutic and diagnostic) in 1H-2024, with PeptiDream developing the products in Japan, and RayzeBio developing the products outside of Japan.' said Patrick C. Reid PhD, President & CEO of PeptiDream.
About PeptiDream Inc.
PeptiDream Inc. (Tokyo Stock Exchange Prime Section 4587) is leading the translation of macrocyclic peptides into a whole new class of innovative medicines to address unmet medical needs and improve the quality of life of patients worldwide. Founded in 2006, PeptiDream employs its proprietary Peptide Discovery Platform System (PDPS) technology, a state-of-the-art highly versatile discovery platform which enables the production of highly diverse (trillions) non-standard peptide libraries with high efficiency, for the identification of highly potent and selective macrocyclic peptide candidates, which then can be developed into peptide-based, small molecule-based, peptide-drug conjugate (PDC) and multi-functional peptide conjugates (MPC)-based therapeutics and diagnostics. PeptiDream has an extensive global network of discovery and development partners driving the development and commercialization of a broad and diversified pipeline of investigational therapeutics. PeptiDream also markets and sells a number of radiopharmaceutical and radiodiagnostic products in Japan, through its wholly owned subsidiary, PDRadiopharma. PeptiDream is headquartered in Kawasaki, Japan.
Contact:
Yuko Okimoto
Email: y-okimoto@peptidream.com
PEPTIDREAM INC. 
