Sanofi weighs Mirati buy as KRAS cancer drug battle enters new phase: Bloomberg

Mirati Therapeutics enjoyed a stock-price spike Thursday after rumors started swirling about a potential buyout by French drug giant Sanofi.

Sanofi has been evaluating a potential acquisition of Mirati, Bloomberg reports, citing people familiar with the matter.

It’s not clear how far the French pharma is with its deliberations or whether the two companies have even started negotiations.

But one thing is clear: After a monthslong downturn since late 2022, Mirati’s stock price surged by around 45% during Thursday afternoon.

Mirati was previously rumored to be an M&A target among Big Pharma companies. But early combination data for its KRAS inhibitor Krazati and Merck’s PD-1 inhibitor Keytruda in KRAS-mutated non-small cell lung cancer disappointed investors and called into question Krazati’s overall market potential.

At that time, analysts figured that whatever deal talks that had happened would have been off the table.

Then, in August, Mirati finally confirmed plans to run a phase 3 trial for the Krazati-Keytruda combination in patients with KRAS G12C-mutant non-small cell lung cancer (NSCLC) who have high levels of PD-L1 expression. This is by itself is a blockbuster market, according to Mirati.

The company’s stock rallied on early-stage data that Mirati shared alongside the phase 3 plan. But shares were still well below prior levels in late 2022.

Meanwhile, Bloomberg’s report came on the same day Mirati’s KRAS rival Amgen went before an FDA advisory committee of external experts to defend its own drug, Lumakras.

The Amgen drug previously showed a benefit in delaying disease progression or death compared with chemotherapy in a confirmatory trial in KRAS G12C-mutated NSCLC. But an FDA internal review flagged several problems of “systemic bias” with the study.

After the discussion, panelists voted 10-2 that they cannot properly interpret the primary endpoint in Amgen’s late-stage study, dubbed CodeBreak 200. 

Still, the agency said it doesn't plan to force the drug off the market right now. 

Krazati currently holds an edge over Lumakras in the next phase of KRAS battle. Serious liver toxicity has forced Amgen to essentially abandon a Lumarkas combination with Keytruda, while the side effect appears manageable for Krazati.

Nevertheless, Mirati has parted ways with its CEO David Meek. Mirati’s founder, Charles Baum, M.D. Ph.D., is now leading the company on an interim basis.

Sanofi's rumored interest follows a flurry of M&A activity for the French drugmaker. Late last year, the company started—but eventually lost—the bidding war for rare disease specialist Horizon Therapeutics. 

Then, in March, Sanofi laid down $2.9 billion for its diabetes partner Provention Bio, the marketer of Type 1 diabetes therapy Tzield. 

More recently, Bloomberg reported the company was involved in talks to buy Reata Pharmaceuticals, which eventually sold to Biogen. 

Before those deals and deliberations, Sanofi bought Ablynx for 3.9 billion euros in 2018, and it purchased Principia Biopharma for $3.7 billion in 2020.