Array's ‘extremely compelling’ new colon cancer data spark blockbuster talk

The news that Array BioPharma’s clinical trial of its triplet therapy for colon cancer extended lives in a trial of patients with the BRAF mutation sent the company’s shares up 23% on Tuesday—a run that was no doubt driven by hopes the therapy will eventually be adopted as the standard of care in that population.

Granted, the company has a long way to go to meet those high expectations. The trial, called Beacon, only involved previously treated patients, and the data didn’t answer key questions about the safety and durability of the treatment, Wall Street analysts concluded.

An interim analysis of the trial showed that a combination of Array's BRAF inhibitor Braftovi, its MEK inhibitor Mektovi and the anti-EGFR drug Erbitux produced a response rate of 26%, vs. 2% for chemotherapy. Overall survival increased from 5 months to 9 months. A separate analysis showed that Braftovi combined with Erbitux produced a response rate of 20% vs. 2%, and that it increased overall survival from 5 to 8 months.

SVBLeerink analysts called the data “extremely compelling”; Beacon marks the first randomized, controlled clinical trial to show an overall survival benefit in this particular population of colon cancer patients.

Analysts at Cantor Fitzgerald predict Array’s triplet treatment would become the preferred therapy—so much so that the firm upped its estimate of peak sales from $770 million to $955 million in 2026.

But to get there, Array will have to answer questions about just how long the benefits from its combo treatment last in BRAF-positive colon cancer patients—and whether they hold up among previously untreated patients.

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Array has a separate trial underway of the triplet as a first-line therapy, called Anchor. But during a conference call on Tuesday, analysts pressed executives for details about whether the Beacon results might be enough to move the treatment into the first-line setting on its own.

Array’s CEO, Ron Squarer, conceded that most colon cancer patients who are prescribed the triplet therapy, should it be approved, would likely have already failed another treatment. But he alluded to the promise of the therapy in the first-line setting. “Once you have overall survival, it really is the gold standard,” he said.

Scott Kopetz, M.D., Ph.D., the lead Beacon study investigator and associate professor of gastrointestinal medical oncology at the University of Texas MD Anderson Cancer Center, echoed that sentiment. “These results certainly maintain and increase the enthusiasm for moving this regimen into first-line therapy,” he said during the call.

It was only a year ago that 20-year-old Array celebrated its first FDA approval, for a combination of Braftovi and Mektovi in patients with melanoma who have BRAF V600E or V600K mutations. The company expects to file for approval of the drugs in colon cancer in the second half of this year, and SVBLeerink analysts say it could be a “prime candidate” for the FDA’s new Real Time Oncology Review program.

The Real Time Review program allows FDA investigators to start analyzing trial data as soon as it becomes public, rather than waiting for companies to actually submit applications to expand a drug’s label. Several companies have benefited from the program, including Merck, with its immuno-oncology blockbuster Keytruda, and Novartis with its breast cancer drug Kisqali.

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Earlier this month, Array posted third-quarter revenues of $64.68 million, beating analysts’ estimates by more than 25%. SVBLeerink analysts predict the new trial results will only drive revenues higher, even before the FDA renders a verdict on the colon cancer application. The analysts said in a note that they “see these data as reaffirming Braftovi/Mektovi's status as the best-in-class BRAF/MEK combination, with a halo effect likely to drive additional uptake in melanoma.”

The next key event for Array could be the ESMO GI conference in July, where investors will be looking for more details about the triplet therapy—particularly its side effects, which the company has not said much about so far. When it released interim data from the colon cancer trial on Tuesday, it said only that the safety profile was “generally consistent with prior reported experience” with MEK, BRAF and EGFR inhibitors.