Novartis <a href="https://www.reuters.com/companies/NOVN.S/"target="_blank">(NOVN.S)</a> has agreed to acquire Seattle-based biotech firm Chinook Therapeutics <a href="https://www.reuters.com/companies/KDNY.O/"target="_blank">(KDNY.O)</a> for up to $3.5 billiā¦