Halozyme collects "mid-single-digit" royalties on the Faspro formulation, Genmab said in a press release. "Genmab intends to vigorously protect its rights under the agreement," the Danish biotech said. The royalty fight comes as J&J posts big growth for Darzalex, which has taken the blood cancer market by storm and posted almost $3 billion in 2019 sales, up 48% year over year.