US pharmaceutical giant Pfizer announced Monday that it had reached a deal to buy biotech firm Seagen, specializing in innovative cancer treatment, for USD 43 billion.

Pfizer is offering USD 229 per share in cash, and the companies expect to complete the transaction later this year or in early 2024, they said in a statement.

"Pfizer is deploying its financial resources to advance the battle against cancer," said Pfizer CEO Albert Bourla.

"Oncology continues to be the largest growth driver In global medicine, and this acquisition will enhance Pfizer's position in this important space," Bourla added.

Seagen -- leading in the research, development and commercialization of cancer treatments -- is growing, with a 12 percent increase in revenue forecast this year to USD 2.2 billion.