 Bloomberg -- Johnson Johnson agreed to pay 6.5 billion in cash to acquire Momenta Pharmaceuticals Inc., a maker of autoimmune-disease drugs, in the largest pharmaceutical-industry merger this year.Though the price tag falls short of some of the industry-shifting takeovers of recent years, the deal is the latest sign drug companies are looking for ways to bulk up even as the coronavirus pandemic upends other businesses.At 52.50 a share, the deal represents a premium of more than 70 to Momentas closing price Tuesday of 30.81. The biotechnology company had seen its shares surge 56 this year after encouraging clinical-trial data for its treatment for a rare blood disorder that affects fetuses and newborns. That treatment has received an orphan-drug designation from the U.S. Food and Drug Administration.Autoimmune diseases have been an area of increasing interest for big drugmakers. Earlier this week, French drugmaker Sanofi agreed to acquire U.S. biotech company Principia Biopharma Inc. for about 3.4 billion. The all-cash deal gives Sanofi treatments for multiple sclerosis and a range of other disorders.Shares of Momenta rose 69 to 52.17 in premarket trading in New York, while JJ shares were up 0.6.Drugmakers werent shielded from disruptions caused by the outbreak of Covid-19 in the U.S. early this year. A sharp decline in elective medical procedures helped curb demand for cancer drugs and other high-priced therapies that have become the industrys main profit engines in recent years.However, many pharmaceutical executives indicated during the most recent earnings season that they believe the most serious effects of the pandemic have passed. And investors have been eager to snap up stocks of drugmakers, especially smaller biotech companies that could become takeover targets. The Nasdaq Biotechnology Index has risen 12 this year, compared with a 4.9 gain for the SP 500, which climbed to a record on Tuesday.JJ said in a statement that acquiring Momenta would bolster its Janssen Pharmaceutical units leadership in immune-mediated diseases. Momenta said in June that its experimental drug nipocalimab hit its primary goal in a phase 2 trial as a treatment for myasthenia gravis, an autoimmune neuromuscular disorder.Both JJ and Sanofi are among several health-care giants that have been racing to develop treatments and vaccines for Covid-19. At the same time, however, pharmaceutical companies battling the pandemic have also been looking for opportunities to expand. Gilead Sciences Inc., the maker of virus therapy remdesivir, agreed to pay 4.9 billion to buy cancer-therapy maker Forty Seven Inc. in March.Shares of some of Momentas peers rallied on the news of the deal. Immunovant Inc. jumped 18 in trading before the U.S. market open, and Argenx SE rose as much as 4.9 in Brussels.Stifel analyst Derek Archila wrote in a note to clients that it is unlikely other bidders will emerge for Momenta.For more articles like this, please visit us at bloomberg.comSubscribe now to stay ahead with the most trusted business news source.2020 Bloomberg L.P. 