When Pfizer shelled out $11.4 billion for Array BioPharma last year, it pointed to early data showing that Array’s BRAF inhibitor Braftovi, its anti-MEK drug Mektovi and the EGFR blocker Erbitux could extend lives in some patients with BRAF-mutant metastatic colorectal cancer (mCRC).
The data was so positive, in fact, it overshadowed the potential of another Array combo in the same patient population—Braftovi plus Erbitux.
Now, Pfizer has nabbed FDA approval for the Braftovi-Erbitux duo in some patients with metastatic BRAF-mutated colon cancer who have already been treated with chemotherapy. It is the first targeted regimen approved in this setting and is “a much-needed new treatment option for these patients,” said Scott Kopetz, M.D., Ph.D., associate professor of gastrointestinal medical oncology at the University of Texas MD Anderson Cancer Center, in a statement The approval was based on results from a trial called Beacon, in which the combination of Braftovi and Erbitux boosted overall survival to 8.4 months from 5.4 months for patients on chemo alone. The response rate for patients who received the duo was 20%, versus 2% for those treated with chemo. Still, the potential addition of Mektovi to the newly approved dual therapy—which was also investigated in the Beacon trial—is what investors have been most excited about in recent months. A few weeks before Pfizer announced the acquisition, Array released interim data showing that the response rate for the triplet therapy in BRAF-mutated mCRC was 26%.
Then in July, Array uncovered more detailed data showing that for the first 331 patients treated, the three drugs reduced the risk of death in mCRC patients by 26%, and that it extended lives by 9.5 months versus 8.3 months for the Braftovi-Erbitux combo. Some analysts concluded that the more mature data favored the triplet regimen.
Analysts at Cantor Fitzgerald aren’t so sure about that, though. They sent a note to investors after the FDA approved Braftovi-Erbitux predicting the duo—not the triplet—would become the standard of care in BRAF-mutated mCRC.
The Cantor Fitzgerald analysts spoke recently to a GI oncologist, who called the Braftovi-Erbitux combo “a likely favorite” for treating colon cancer patients who had already received chemotherapy, they said in a note to investors earlier this week.