Less than three months after it was acquired by its biggest investor, Quark Pharmaceuticals is preparing to begin a pivotal study of its neuroprotectant agent QPI-1007 in the ocular disease non-arteritic anterior ischemic optic neuropathy.
According to Quark President and CEO Daniel Zurr, the acquisition has given the company a fresh infusion of capital that will allow it to begin the phase III trial, which would not only provide data for a potential regulatory approval but also lay the groundwork for a phase II trial of the drug in the more lucrative indication of glaucoma.
According to Japan’s SBI Group, its subsidiary SBI Biotech acquired all the shares of Quark around the end of 2012. As a result, Quark has become a wholly owned subsidiary of SBI Biotech.
However, Zurr told Gene Silencing News that the deal has not affected Quark’s management or its business strategy, which is centered around three clinical candidates.
The first, QPI-1007, is composed of siRNAs designed to inhibit the pro-apoptotic gene caspase 2 and is being developed to treat NAION, a rare disorder characterized by the death of retinal ganglion cells — the same cause of glaucoma-related blindness.
About a year ago, Quark released interim phase I data that indicating that the intravitreally delivered drug could protect ocular neurons and improve visual acuity in NAION patients (GSN 1/12/2012). Zurr said that a phase IIa arm of that study has also now been completed, and while the results were not announced, the company is planning to continue its development.
Specifically, Quark is preparing to begin a pivotal study of QPI-1007 that could provide data sufficient to support its regulatory approval, Zurr said. That trial is expected to enroll up to 240 NAION patients in China, India, the US, and other nations, and begin in “the next few months.”
However, Quark has long had its sights set on developing QPI-1007 for glaucoma, and Zurr said that once the pivotal trial in NAION is completed, the company will begin testing the drug for that disease.
Because it has already collected safety and tolerability data for QPI-1007 in NAION, he added that Quark expects to move directly into phase II for glaucoma — most likely the angle-closure form of the condition, which causes a sudden and rapid rise in intraocular pressure and is typically treated with surgery, Zurr said.
Also continuing to move through Quark’s pipeline is QPI-1002, an siRNA-based inhibitor of p53 in clinical trials for the prevention of acute kidney injury following cardiovascular surgery and for the prevention of delayed graft function after renal transplantation.
Currently, the drug is in a phase I/II trial in patients undergoing deceased donor kidney transplantation. The phase I arm is designed to evaluate escalating doses of QPI-1002 in around 40 patients to find the maximum tolerated dose. The other arm will enroll up to 326 patients to test the safety and clinical activity of that top dose.
Zurr said that this trial is expected to conclude around the end of the year, providing a dataset that Novartis, which holds an option to license the drug in all indications, will use to determine if it wants to take QPI-1002 toward commercialization.
A phase I study studying the ability of QPI-1002 in treating prevention of ischemia-reperfusion-induced kidney injury in patients removed from a cardiopulmonary bypass pump has already been completed, and he said phase II development would begin upon completion of the delayed graft function study.
Lastly, Quark continues to work on PFE-655, which silences a proprietary gene target called RTP-801.
In 2006, Pfizer acquired the rights to the target and the drug for certain diseases including diabetic macular edema and wet age-related macular degeneration (GSN 9/28/2006).
In early 2011, Quark disclosed that a phase II trial in DME was halted early after Pfizer decided that the drug was unlikely to provide a therapeutic benefit superior to the current standard of care. The companies then amended their arrangement so that Quark would assume responsibility for a new phase IIb trial evaluating a higher dose of PFE-655, with Pfizer having the option to back out of the arrangement based on the results of that study.
Zurr said that the phase IIb is also slated to wrap up around the end of this year.
Quark had long been interested in going public in the US, and in 2007 filed with US regulators to float its shares on the Nasdaq for between $12 and $14 apiece. However, it eventually abandoned that plan amid weak investor interest.
In 2010, the company once again filed for an initial public offering, only to scuttle that effort because the “terms currently obtainable in the public marketplace are not sufficiently attractive … to warrant proceeding with the public offering.”
As recently as last February, Zurr had expressed interest in making another attempt at an IPO, but it seems that SBI Biotech may be the one going public.
In a statement announcing the transaction, SBI Biotech said that it is currently preparing to list its shares, as early as this year, although it did not provide details on whether the listing would occur in Japan or another country.