Sanofi to acquire immuno-oncology firm Amunix

Sanofi has agreed to acquire Amunix Pharmaceuticals, a California-based immuno-oncology drug developer, for about $1 billion and up to $225 million in milestone payments. The purchase continues Sanofi’s streak of buying companies that seek to fight cancer by modulating the immune system.

Amunix was founded over 15 years ago but didn’t raise its first major funding round—a $73 million series A—until 2020. It brought in another $117 million in March 2021.

The company’s lead product, AMX-818, has yet to enter clinical trials. AMX-818 is a protein that recruits immune cells called T cells to target HER2, a kinase expressed on several solid tumors. The drug uses Amunix’s XTEN technology, which is based on a polypeptide that masks the protein until it’s in the disease environment. The firm says the approach can eliminate the widespread immune system activation that is a serious side effect of some immuno-oncology drugs.

Commenting on the acquisition in a note to clients, SVB Leerink stock analyst Geoffrey C. Porges says he believes most of Amunix’s value is in the XTEN technology rather than AMX-818 itself. “If even one unique medicine emerges based on this technology, the acquisition price should be reasonable,” he says.

Amunix marks the sixth acquisition that Sanofi has announced this year, Porges says, all of them focused on immunology, immuno-oncology, and messenger RNA. In September, for example, Sanofi agreed to buy the immuno-oncology drug developer Kadmon Holdings for $1.9 billion.

Given the depressed valuations of small and midsize biotech firms at present, Porges expects Sanofi to continue acquiring. “We would not be surprised to see additional tuck-in deals over the next year,” he says.