Array shows off the positive BEACON CRC data that helped spur Pfizer's $11.4B buyout offer
Investigators took center stage at a scientific conference today to tout the positive data from the BEACON CRC trial of Array’s BRAF/MEK triplet for drug resistant colon cancer that played a key role in attracting Pfizer’s $11.4 billion buyout bid.
The FDA had already stamped its breakthrough designation on the triple therapy of (Braftovi) encorafenib in combination with (Mektovi) binimetinib and cetuximab before Pfizer execs were provided a glimpse of the top-line results in May — whetting their appetite for the acquisition during the final days of their negotiations. That’s when they learned that the triplet scored a median overall survival rate of 9 months among drug resistant patients with BRAF V600E-mutated cases of colorectal cancer compared to 5.4 months for the standard of care.
The ORR was 26% in the triple therapy drug arm, compared to just 2% in the SOC group. And while there was a high, dose-related rate of adverse events — with Grade 3 or above AEs in 58% of patients on triplet treatment and 50% of those in the doublet group — that still compared well with the 61% rate of Grade 3 or higher AEs among those in the standard therapy group.
Evercore ISI’s Umer Raffat took a look at the data and couldn’t quite figure whether the triplet or doublet would be preferred — a major consideration while trying to factor the revenue potential for Pfizer.
I acknowledge that overall survival for ITT population still tracks 21% better (but not stat sig yet) for triplet vs doublet … however, the consistency of data in first half of pts (331) vs next half is puzzling … and PFS did not help either. In a silio, I’d argue that given the cost differences + questions on incremental efficacy with triplet vs doublet, we may see limited uptake of triplet. However, in practice, physician experience of using BRAF+MEK combo in melanoma likely exerts a very positive halo effect over to CRC indication also … and, the OS HR of 0.79 helps with an added datapoint.
BEACON @ARRAY trial results for the phase III BRAF MT mCRC: Improved for triplet (HR= 0.52) and slightly less for the doublet (HR = 0.60) vs. control for OS, PFS, and RR;best RR if used earlier.#WorldGI2019 @WCGIC @esmo #colon #Cancer #cancerresearch #clinicaltrials @VUMC_Cancer pic.twitter.com/1e5lyfXVFj
— Dr. Cathy Eng (@CathyEngMD) July 6, 2019
The data were presented at the ESMO World Conference on Gastrointestinal Cancer.
“These are very exciting results because we’ve been trying to target BRAF-mutant colorectal cancer for many years. It’s encouraging to see such a significant improvement in overall survival and response in patients with such aggressive tumor biology. Hopefully, this will soon lead to increased access to this treatment for patients where there is currently such a large unmet need,” said study author Scott Kopetz, from the MD Anderson Cancer Center, in a prepared statement.
These results were crucial to Array’s negotiations with Pfizer, and they “shared high-level top line results data” with the pharma giant’s execs on May 17, 4 days ahead of the top-line announcement, as outlined in a recent SEC filing. Twelve days later Pfizer CEO Albert Bourla made his first hard offer at $44 a share, settling soon after at $48.