Which big brands will still be bringing in the big bucks in 2020?

Humira will bring in $12.7 billion in global sales by 2020, according to a new report by EvaluatePharma.

Best-selling drugs did well for themselves in 2013, churning out more than $76 billion in sales. But big-name brands could stand the test of time and help the top 10 rake in more than $80 billion in 2020, according to a new report.

Among the drugs that snagged top spots in EvaluatePharma's annual world preview report, AbbVie's ($ABBV) Humira is slated to remain the biggest global brand through 2020. The inflammatory drug is set to bring in $12.7 billion in 2020--a 15% increase from 2013, when it posted $11 billion in sales.

Despite the fact that copycat versions of Sanofi's ($SNY) top-selling diabetes drug Lantus are on the way, EP expects the powerhouse drug to keep growing, from an estimated $7.59 billion to $10.25 billion. But Lantus is not the only drug staying afloat in the lucrative diabetes pool. Merck's ($MRK) Januvia franchise will also keep a top spot, with worldwide sales projected to reach $6.89 billion in 2020.

Autoimmune drugs will also hold their own, with Amgen's ($AMGN) TNF inhibitor Enbrel enjoying patent protection through 2028 that should ward off generic competitors. Janssen's Remicade, a monoclonal antibody (mAb) therapy for rheumatoid arthritis (RA) and Crohn's disease, will also maintain steady global sales--but a quickly approaching U.S. patent expiration in 2018 could put a damper on things.

Then there's Roche's ($RHHBY) colon cancer drug Avastin, which will hang around, too, coming in at $6.61 billion in 2020 despite a slight sales dip from the $6.75 billion it put up in 2013. And a new cancer product-- Bristol-Myers Squibb's ($BMY) as-yet-FDA-unnapproved immuno-oncology drug nivolumab--will quickly win a spot among the top sellers, EP predicts, pegging 2020 global sales at $6.36 billion.

Gilead's Sovaldi--Courtesy of Gilead

Nivolumab won't be the only relative newcomer to join the list of giants. Not to be outdone, Bayer and Johnson & Johnson's ($JNJ) Xarelto will rack up $6.41 billion in sales, too--more than three times its 2013 haul of $1.95 billion, EP says. Biogen Idec's ($BIIB) multiple sclerosis wunderkind Tecfidera will pass the $6 billion sales mark as well, expanding at a compound annual growth rate of 33%. Gilead's ($GILD) hep C wonder drug Sovaldi is also predicted to grow by leaps and bounds. EP forecasts 2020 sales at $8.02 billion--a whopping increase from 2013's $139 million. But Sovaldi sales could slow down as other hep C drugs enter the playing field.

- here's EP's report

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