COPENHAGEN, May 7 (Reuters) - Danish biotech company Genmab posted a 231 percent jump in first-quarter operating profit, mainly driven by increased revenue related to its collaboration with Janssen, a part of Johnson & Johnson, the company said on Wednesday.

The company, whose only drug on the market is blood cancer treatment Arzerra, lifted its operating profit to 96 million Danish crowns ($17.9 million) from 29 million a year before.

Revenue increased by 87 million crowns to 247 million crowns, mainly driven by a 119 million milestone payment received from Janssen in March..

The company kept its 2014 operating income outlook of between 140 million crowns and 210 million, having upgraded it earlier this month..

Genmab also expects 2014 operating expenses in a range of 600 million crowns to 650 million.

($1 = 5.3612 Danish Crowns) (Reporting by Stine Jacobsen; Editing by David Holmes)