Verastem's low-stakes comeback gamble on an AbbVie/Infinity castoff pays off with positive CLL data
Verastem CEO $VSTM Robert Forrester was able to pick up the late-stage cancer drug duvelisib from a badly wounded Infinity Pharmaceuticals late last year for exactly nothing up front. And now he’s setting out to prove that the drug is a steal, offering up one incomplete but positive snapshot of top-line Phase III data to prove that he has a shot at a near-term approval that could be worth up to $300 million a year in the US market alone.
Verastem’s newly acquired PI3K-delta/gamma inhibitor hit the primary in the 4-year study, achieving a progression-free survival rate of 13.3 months among relapsed or refractory chronic lymphocytic leukemia /small lymphocytic lymphoma patients compared to 9.9 months for Novartis’ Arzerra (ofatumumab). Break it down to median PFS in the subset of hard-to-treat patients with 17p deletion randomized to duvelisib, and you also get a significantly higher 12.7-month rate for their drug compared to 9.0 months for the comparator, along with a shot at a clearly defined niche.
For Verastem, that hit on the primary endpoint is good enough to start discussions with the FDA on filing for an approval. In Forrester’s words, “it’s everything we hoped for and more.”
Investors loved what they saw, with Verastem shares spiking 44% on the news.
“This fits nicely in the CLL marketplace,” Forrester adds, which is transitioning from chemo being the traditional route of treatment to a new set of oral drugs like duvelisib that can help an older group of patients treat themselves at home, maintaining their quality of life as well as life expectancy.
The PFS rate, though, is one of several key measures the trial studied. Researchers also explored overall response rates as well as overall survival for the secondaries. Pressed, Forrester conceded that he has the ORR data in hand, but won’t release it until a later scientific conference sometime in the near future.
What he does say, though, is that the data back Verastem’s plan to roll this drug out themselves as a second or third-line CLL drug in the US, looking to grab 15% to 20% of the market in that niche, which Forrester estimates is worth $200 million to $300 million a year. Partners can be found for the rest of the world.
Verastem is also adding a program for peripheral T-cell lymphoma for duvelisib as it looks to expand indications following the first OK, provided that comes through.
Duvelisib was once a blockbuster prospect, up until Infinity outlined positive but disappointing Phase II data, with a 46% ORR rate for indolent non-Hodgkin lymphoma. AbbVie, which had inked an $805 million deal with Infinity to get this in their pipeline, promptly turned their backs on the drug and walked — satisfied that the positive data did not translate into a solid commercial opportunity.
Infinity, which had seen two previous lead drugs crushed by bad data, was hit hard. Its stock price was eviscerated, the biotech was forced to restructure and lay off staffers, and CEO Adelene Perkins was charged with unloading the drug ASAP.
That’s when Forrester called. He wound up getting the drug in a deal that includes just $28 million in milestones: $6 million for a positive Phase III and $22 million on approval.
Verastem has also known what it’s like to be stung by failure. Close to two years ago now, after initially defending the data, Forrester admitted that their lead drug defactinib (VS-6063) had failed its most advanced study for mesothelioma, a difficult-to-treat type of lung cancer associated with repeated contact with asbestos. This came after the drug showed poor efficacy and serious adverse events in a study for non-small cell lung cancer. Its stock was crushed, and that biotech also restructured.
The FDA has been known to approve drugs based on similar data, or worse. But there are still some important questions on duvelisib that will need to be asked and answered. But Verastem is one step closer to a major objective.