BOULDER, Colo.—Essentially merging two research anddevelopment programs for small-molecule checkpoint kinase 1 (ChK-1) compounds,Array BioPharma has signed an oncology agreement with Genentech to exploreGenentech's compound GDC-0425 (RG7602), currently in Phase I trials, andArray's compound ARRY-575, which is being prepared for an investigational newdrug application to initiate a Phase I trial in cancer patients.
Under the terms of the deal, Genentech is responsible forall clinical development and commercialization activities. For its part, Arraywill receive an upfront payment of $28 million, is eligible to receive clinicaland commercial milestone payments of as much as $685 million and could receivedouble-digit royalties on sales of any resulting drugs. No additional financialterms have been disclosed.
"Combining both companies' programs will maximize ourchances for success in developing and commercializing this novel cancertherapy," said Robert E. Conway, CEO of Array BioPharma, in the officialannouncement about the deal, calling the new deal an expansion of his company'slong-standing relationship with Genentech. "We believe ChK-1 inhibition is akey strategy for enhancing the efficacy of chemotherapeutic and other agents incancer patients."
The deal is unique and "pretty unusual" by the normal pharmaand biotech industry standards, Conway tells ddn.
"This represents some remarkable economies and economics, aswe sweep our compounds together into a joint program and figure out whichprogram should move forward into later-stage development based on the trialdata," Conway continues. "We were looking for a great partner already, andwe've been working with Genentech on oncology programs for several years now.Our ChK-1 program goals and company goals align very well, and we're happy tohave Genentech driving the bus on this. The same economics apply regardless ofwhich drug moves forward."
"This is a great way to sort of double our chances ofsuccess in reaching the market with a ChK-1 drug and get cures to patientsfaster," adds Kevin Koch, president and CSO of Array.
"Genentech has had a relationship with Array since 2004 on anumber of programs so we have a good sense of their scientific prowess," Dr.James Sabry, vice president of Genentech Partnering, tells ddn. "Afundamental respect for science has been a deep and abiding part of Genentech'sculture—an outlook that's been maintained after our acquisition by Roche. Wealready had that positive relationship with and respect for Array, and when werealized they had a program much like ours in ChK-1, it made sense to do a dealstructure like this."
Combining the two programs has great appeal in part becausedrug attrition is such a huge financial drain on pharma and biotech companies.With two compounds to pursue, Sabry notes, the overall costs will be higherthan going it alone, but the chances of success are so much better than itmakes it worth the somewhat elevated cost.
Only one of the two compounds is likely to move forward,though, so increased costs of R&D won't be a long-term issue, he adds.
"There's no particular reason we couldn't theoretically goforward with both," Sabry notes, "but it's not likely. Both compounds have verysimilar mechanisms of action, so there probably wouldn't be much benefit to usor patients to move both forward. The trial results will help us to determinewhich of the two seems most promising."
ChK-1 is a protein kinase that regulates tumor cells'response to DNA damage that is often caused by treatment with chemotherapy. Inresponse to DNA damage, ChK-1 blocks cell cycle progression in order to allowfor repair of damaged DNA, thereby limiting the efficacy of chemotherapeuticagents.
The companies believe that by inhibiting ChK-1 in combinationwith chemotherapy, they can enhance tumor cell death, and they say that bothGDC-0425 and ARRY-575 are highly selective, oral ChK-1 inhibitors designed toenhance the efficacy of some chemotherapeutic agents.