TOKYO--(BUSINESS WIRE)--PeptiDream Inc., a public Tokyo-based biopharmaceutical company (“PeptiDream”)( TOKYO:4587) announced today, in collaboration with The Tokyo Metropolitan Institute of Medical Science (“Tokyo Metropolitan Institute”) the discovery and development of a novel macrocyclic peptide inhibitor for the treatment of multiple influenza strains.
Tokyo Metropolitan Institute has been leading a broad-based discovery effort for novel treatments for influenza, funded by the Japanese government and initiated in 2008. PeptiDream joined the discovery consortium taking a peptide-based approach using PeptiDream’s proprietary Peptide Discovery Platform System (PDPS) to identify novel macrocyclic peptide inhibitors for influenza.
Two marketed therapeutics, Relenza (GSK) and Tamiflu (Roche), inhibit the neuraminidase enzyme on the influenza virus surface, yet these therapeutics are only effective shortly after viral exposure and are less effective against newer influenza strains, thus there is immediate need for other more effective treatments with different mechanisms of action.
The partnership focused on the discovery of novel peptide inhibitors of the influenza hemagglutinin (HA) protein found on the surface of influenza viruses and responsible for the binding and entry of virus to cells. PeptiDream identified lead peptide candidate iHA-24 which exhibited high affinity and selectivity for the HA protein. In addition, the macrocyclic peptide was highly effective in preventing both viral infection and viral proliferation in both cell-based experiments and mouse-based animal studies, and was more effective than any commercially available treatments. Peptide iHA-24 also exhibited broad influenza strain efficacy against H1N1 (2009 pandemic strain), H5N1 (bird flu, SARS), and H2N2 strains.
In light of these breakthrough results, pre-clinical testing in cynomolgus monkeys is slated to begin in May 2014. Successful validation of efficacy will lead to the preparation of a complete preclinical development data package for investigational new drug (IND) application slated for 2015.
[Comments from Dr. Michinori Kohara, Director of Viral Infectious Disease Project at Tokyo Metropolitan Institute of Medical Science]
“We have been working for some time to develop an antibody therapeutic to treat influenza targeting the HA protein, and PeptiDream provided an attractive alternative by developing a peptide therapeutic, capable of recognizing antigenic regions that conventional antibodies cannot reach because of their significantly larger size. iHA-24 was found to exhibit inhibition activity equal to or even higher than that of the current neuraminidase inhibitors. In addition, we showed that iHA-24 could effectively inhibit the pandemic H1N1 2009 strain, of which some variants were resistant to neuraminidase therapeutics. These exciting findings establish peptide therapy as new anti-viral agents for the treatment of influenza. We intend to continue pre-clinical testing in monkey trials, while we rapidly prepare for clinical testing.”
[Comments from Kiichi Kubota, CEO of PeptiDream Inc]
“We believe our macrocylic peptides represent an exciting new approach to more effectively treating influenza virus, and also toward the prevention of future influenza outbreaks. In collaboration with Dr. Kohara’s team, we are excited to start preclinical testing in monkeys with the aim of bringing these peptides into human testing in 2015. This program represents one of the many exciting discovery and development programs progressing at PeptiDream, and we would like to thank Dr. Kohara and the staff at the Tokyo Metropolitan Institute of Medical Science for all of their efforts.”