Danish biotech Genmab has seen its shares double in three months after a string of major cancer drug trial successes

Danish biotech Genmab has seen its shares double in three months after a string of major cancer drug trial successes, giving fresh momentum to its push to take greater control of the medicines it develops and sells. After nearly three decades spent building Genmab into one of Europe's prominent biotechnology companies, CEO Jan van de Winkel told CNBC on Friday the breakthroughs marked "a completely new era." Historically, Genmab made money from royalties from drugs it helped develop, including Johnson & Johnson's multiple myeloma treatment Darzalex and Novartis' Kesimpta. Van de Winkel said Johnson & Johnson is expected to generate $16.5 billion to $16.9 billion in Darzalex sales this year, with Genmab receiving royalties of up to 20%. Genmab is now using that financial firepower to build a business that keeps a much larger share of the revenue from its own treatments.