Dive Brief:

• Genmab said Wednesday it’s agreed to pay $1.8 billion for ProfoundBio, gaining access to the biotechnology startup’s technology for developing antibody-drug conjugates, or ADCs.

• ProfoundBio’s portfolio includes Rina-S, a newer type of ADC it claims to be a potentially best-in-class medicine. The drug is designed to target tumors that express a protein called folate receptor alpha and is currently in Phase 2 testing for ovarian cancer and certain other types of solid tumors.

• The all-cash transaction is expected to close by the end of June. The Danish drugmaker said the purchase will result in extra expenses this year as the company takes on responsibility for developing Rina-S and other ProfoundBio experimental medicines. It expects to update investors on its financial outlook upon releasing second-quarter earnings.

Dive Insight:

ADCs offer the promise of delivering deadly medicine into tumors without disturbing the healthy cells in the body. To do this, the drugs combine chemotherapy with antibodies that can specifically seek out cancerous cells before unleashing toxins.

ADC drug developers struggled for years. But technical advances and clinical successes have made them an increasingly compelling story for drugmakers, who have ponied up tens of billions of dollars of late to gain access to the medicines.

In December, Bristol Myers Squibb entered an ADC partnership with SystImmune that could be worth as much as $8.4 billion. Merck & Co. has been active in the field too, announcing a potential $22 billion alliance with Daiichi Sankyo in October and striking multiple deals before that. Those agreements followed $16.6 billion worth of ADC licensing deals in 2022, according to the analytics company Global Data.

The field has also seen a flurry of acquisitions. In January, Johnson & Johnson agreed to pay $2 billion for Ambrx Biopharma. That followed the November announcement of AbbVie’s $10 billion buyout of ImmunoGen. And in March last year, Pfizer inked a $43 billion deal to take over Seagen, one of the pioneers in the field.

Previously known as Seattle Genetics, Seagen developed the lymphoma medicine Adcetris and secured three other drug approvals in recent years. A number of Seagen veterans now run ProfoundBio, which demonstrated investor appetite for its technology with a $112 million funding round in February.

Genmab has worked with Seagen in the past, developing an ADC called Tivdak. With the ProfoundBio deal, the company now has its own ADC platform to strengthen an oncology portfolio that includes the multiple myeloma medicine Darzalex, developed with J&J, and the AbbVie-partnered lymphoma drug Epkinly.

ProfoundBio’s lead drug, Rina-S, is a would-be competitor for Elahere, which AbbVie recently scooped up with the closing of its ImmunoGen acquisition. Rina-S is currently in Phase 2 of a Phase 1/2 trial, and Genmab said it plans to “broaden development plans” for the drug based on early data.

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