Karyopharm Therapeutics raised close to $50 million just a few months ago to continue developing its lead cancer drug. Now it’s turning to Wall Street to help with the effort.
Karyopharm filed a Form S-1 with the SEC late Friday outlining plans to raise up to $80 million through an IPO, hoping to capitalize on the wide open window for life sciences offerings and help push its lead drug, now known as selinexor, into at least two—and potentially four—mid-stage clinical trials next year. The Natick, MA-based biotech aims to trade on the Nasdaq under the symbol “KPTI.”
According to its IPO prospectus, Karyopharm has raised about $100 million from investors to date. Two investment vehicles controlled by private investors Marcin Czernik, Andreas Hadjimichael, and Amalia Hadjimichael are, by far, Karyopharm’s largest stockholders: Chione Ltd., (46.8 percent of Karyopharm’s stock), and Plio Ltd. (14.6 percent). Entities associated with Foresite Capital (9.42 percent) and Delphi Ventures (8.17 percent) also hold large pieces of the company’s equity.
Bank ofAmerica Merrill Lynch, Leerink Swann, JMP Securities, and Oppenheimer & Co. are underwriting the IPO.
Karyopharm plans to use the cash to ready a big clinical push over the next year for selinexor, a drug candidate that is supposed to work by protecting the body’s natural tumor-suppressing proteins. Healthy people have such proteins in their cells, preventing those cells from becoming cancerous. In patients with cancer, however, a protein called CRM1 carries the tumor fighters out of the nucleus of the cells, leaving them vulnerable. Karyopharm is creating a group of drugs designed to bind to CRM1—also known as Exportin-1, or XPO-1, for short—and keep the anti-cancer proteins in the nucleus. Karyopharm isn’t aware of any other drugs with this approach in clinical development, it said in its S-1.
Karyopharm plans to develop a pipeline of drugs with this approach to treat cancers in both humans and dogs, and to go after autoimmune disorders such as multiple sclerosis as well. While the company has been able to raise a lot of financial support for the theory, however, it still has a long way to go to prove that it really works. Selinexor has so far been tested in over 170 patients with a variety of blood cancers, but that work has been done in three early-stage trials, which were designed to assess the drug’s tolerability and whether it was doing its job of keeping the tumor-suppressing proteins in the nucleus. Karyopharm will really find out how effective selinexor is at treating cancer its next go-around in the clinic. It hopes to start two Phase 2/3 clinical trials—studies that contain elements of both mid-stage, and late-stage trials—of the drug candidate in two unspecified cancer types in the first half of 2014. It also hopes to begin two mid-stage studies in patients with certain solid tumor types next year as well.
Karyopharm had about $17.7 million in cash on hand as of June 30, and hopes to use the IPO dollars primarily to fund those studies.
The company is also developing a second drug known as verdinexor, a version of selinexor for dogs with lymphoma. That drug is in phase 2 development, and Karyopharm noted that its success is very important to the success of selinexor. If verdinexor fails, for example, the FDA may require more data to support the approval of selinexor, it said in the prospectus.
Karyopharm intends to keep U.S. and European rights to its drug candidates, though it may seek out a partner to help commercialize them in other geographic areas such as Asia.
The company is headed by CEO Michael Kauffman, formerly of Millennium Pharmaceuticals, Proteolix, and later Onyx Pharmaceuticals after Proteolix was acquired by the South San Francisco, CA-based firm.
