Silenseed cans Nasdaq IPO as RNAi-cancer pitch fizzles

Silenseed has formally scrapped its plan to list on Nasdaq. The developer of RNAi-based cancer drugs pitched up on Wall Street more than one year ago with a view to raising $36.4 million (€33.9 million), but has now admitted defeat.

Silenseed CEO Amotz Shemi

Modi'in-Maccabim-Re'ut, Israel-based Silenseed revealed the climbdown in a letter to the Securities and Exchange Commission (SEC), in which CEO Amotz Shemi requested to withdraw the registration statement filed with the regulator last year. Silenseed submitted its original paperwork in June 2014, at which time the U.S. biotech IPO market was in the midst of a prolonged hot streak. Yet despite the willingness of investors to funnel billions of dollars into biotechs over the past 18 months, Silenseed has canned its attempt to raise money.

Silenseed set out to raise the cash to fund the advance of its pancreatic cancer asset, siG12D-LODER, through late-phase trials and onto a filing for regulatory approval with the U.S. FDA. The program, which uses Silenseed's siRNA delivery tech to overcome the challenges of targeting KRAS, has come through a Phase I/IIa trial and picked up orphan drug status from the FDA. With these milestones behind Silenseed, it planned to pump $16 million of the IPO haul into a 124-person Phase II trial, which is currently slated to start next month. A further $6 million was earmarked for preclinical tests in other diseases.

Silenseed's inability to extract this money from public investors marks the latest twist in the topsy-turvy relationship between Israeli biotechs and the U.S. stock exchange. A record number of Israeli biotechs floated on Nasdaq last year, pulling in $472 million in the process. But many companies have failed to raise as much as they initially targeted, while VBL Therapeutics ($VBLT) cancelled its first IPO after shares were listed for trading and Mapi Pharma has yet to list despite trying on three separate occasions, the latest of which is ongoing.

- read the statement