Danish drugmaker Genmab A/S said Thursday it could get more than $1 billion from health care giant Johnson & Johnson as the companies develop an experimental cancer treatment.

The companies agreed to collaborate on Genmab’s cancer drug daratumumab. Genmab is running clinical trials of the drug as a treatment for multiple myeloma, and the companies suggested they may study it as a treatment for other types of cancer including acute myeloid leukemia. Johnson & Johnson’s Janssen Biotech unit will have exclusive worldwide rights to develop and sell daratumumab.

Janssen agreed to pay Genmab about $55 million up-front and make an $80 million investment in the company, giving it a 10.7 percent stake. Genmab could receive $1 billion in further payments if daratumumab progresses through clinical testing, regulatory review, and reaches sales targets. Genmab said it will also get royalty payments of more than 10 percent on sales.

Janssen will cover the costs of two current clinical studies and all other trials afterward.

Multiple myeloma is a type of cancer that causes tumors to grow in the bone marrow, preventing the production of normal blood cells.

Genmab said it now expects 435 million to 460 million kroner ($73.3 million to $77.5 million) in revenue this year, up from a previous estimate of 375 million to 400 million ($63.2 million to $67.4 million)

Genmab’s only approved product is Arzerra, a treatment for chronic lymphocytic leukemia. Genmab and GlaxoSmithKline PLC are also studying Arzerra as a treatment for other types of lymphoma, rheumatoid arthritis, and multiple sclerosis.