The kinase killers
SOUTH SAN FRANCISCO, Calif.—Sunesis Pharmaceuticals Inc. and Millennium: The Takeda Oncology Company have formed a license agreement for developing Sunesis' oral, selective pan-Raf kinase inhibitor, as well as one other undisclosed kinase inhibitor program in oncology.
"These kinase inhibitor programs represent an important addition to our portfolio and reflect our strategy to develop novel oncology therapies by targeting the underlying pathways of the disease process," says Dr. Nancy Simonian, chief medical officer at Millennium.
In 2004, Sunesis formed a multikinase inhibitor collaboration with Biogen Idec, which included the two programs Millennium acquired. In November 2010, Biogen Idec announced its intention to focus on neurology and subsequently outlicense its various oncology assets, two of which were acquired by Millennium, which will continue developing the assets in collaboration with Sunesis.
"After a number of companies expressed interest, Millennium was the best partner to take this program forward," says Daniel Swisher, CEO of Sunesis.
Biogen Idec and Sunesis will continue to work together on a separate collaboration, focusing on a preclinical kinase inhibitor program in the realm of immunology. Steven Holtzman, executive vice president of corporate development at Biogen Idec, says the company is "delighted to transition our collaboration with Sunesis on these oncology programs to Millennium, a world- class oncology organization."
"We look forward to seeing the oncology programs progress under Sunesis and Millennium's new collaboration as we continue to drive forward our partnership with Sunesis on our immunology program," Holtzman says.
Per the collaboration agreement, Sunesis has received an upfront payment from Millennium of $4 million and is eligible to receive up to $60 million in precommercial milestone payments, as well as royalties on sales of future products that result from the collaboration. Sunesis also retains future co-development and co-promotion rights.
This is Sunesis' first collaboration with Millennium.
"We are very excited to be working with Millennium, a company that focuses on developing first-in-class and best-in-class oncology compounds," says Swisher. "We look forward to Millennium's transition of the pan-Raf kinase investigational agent into clinical studies, while we continue to focus our resources and attention on our ongoing Phase III VALOR trial for vosaroxin in AML."
The Raf kinsases—which include A-Raf, B-Raf and C-Raf—are key regulators of cell proliferation and survival within the mitogen- activated protein kinase (MAPK) pathway. Swisher says that the MAPK pathway is disregulated and mutated in "approximately 15 percent of human cancers and 40 to 70 percent of melanomas and anaplastic thyroid cancers," which illustrates the potential these programs have to provide benefit to a variety of different areas of cancer.
Non-clinical data from the oral and selective pan-Raf inhibitor were presented in November at the EORTC-NCI-AACR meeting. The data presented demonstrated potent pan-Raf kinase inhibition in biochemical kinase assays. Additional data showed significant antitumor activity in large B- Raf mutant melanoma tumor models, as well as in tumor models of B-Raf wild-type melanoma and other B-Raf wild-type tumor types.
Swisher says there is "hopefully very significant" commercial opportunity for the kinase inhibitors, noting that some recent B-Raf inhibitors have reported Phase III data and are "moving towards the market as a new treatment for metastatic melanoma cancer, which is a very significant unaddressed medical need."
"These pan-Raf inhibitors have the potential to also be new standards of care in that setting, and hopefully expand into additional solid tumor settings," Swisher states, though he says it is "a little bit premature to speculate on the exact commercial opportunity, given that we're just starting Phase I trials later this year."
Simonian also notes, "the Raf kinase inhibitor investigational agent offers a compelling development opportunity as it targets a clinically validated pathway."
"We look forward to building on the strong preclinical dataset as we advance this program into clinical trials," says Simonian.