Massachusetts-based biotechnology company Biogen is considering to make investments in drug assets takeover with $18 billion capital, starting in 2019.

Biogen said that it would buy U.S.-based drugmaker Alder Biopharmaceuticals' migraine prevention drug, eptinezumab, and a depression treatment drug, SAGE-217, owned by rival Sage Therapeutics.

Biogen said that it has about $4 billion to $5 billion in cash bringing its total purchasing power in the range of $17 billion to $18 billion.

Earlier in the week, Biogen completed $13 billion financing round.