Pfizer to purchase cancer drugmaker Seagen for $43 billion

Pfizer Inc. said it will purchase cancer-drug maker Seagen Inc. for an enterprise value of $43 billion, gaining the company’s antibody drugs that fight tumors.

Pfizer will pay $229 a share in cash for Seagen, according to a statement on Monday, about a third more than the drugmaker’s closing share price of $172.61 Friday.

Seagen is a leader in developing a different type of medicine called antibody-drug conjugates, or ADCs. These precision medicines deliver cancer-killing drugs so potent they might otherwise be too toxic to use. The new delivery mechanism uses antibodies to deposit a strong concentration of drug directly at a tumor site, which may increase efficacy with fewer side effects.

Pfizer expects to finance the transaction substantially through $31 billion of new, long-term debt, and the balance from a combination of short-term financing and existing cash, according to the statement. Seagen is expected to contribute more than $10 billion in risk-adjusted revenues in 2030.

Shares of Seagen have gained 34 per cent since the year began, giving the company a market value of about $32.2 billion.