Biogen may face uncertainty in multiple sclerosis, a new rival to its quick-launching SMA blockbuster, and setbacks in its pipeline, but its biosimilars group is zooming ahead.

Biosimilar sales grew 45% to $184 million year-over-year, and that's with just a few of its products on the market—and those only in Europe. As of now, the company sells E.U. copycats to Merck's Remicade, Amgen's Enbrel and AbbVie's Humira.

True, that's only a small fraction of Biogen's overall sales, but execs with the company clearly sees big things ahead. After all, it amped up its investment in its biosim joint venture with Samsung last year.

On a conference call Tuesday, Biogen CEO Michel Vounatsos said the company's Imraldi is a "market-leading" biosim to AbbVie’s blockbuster Humira. That drug generated $47 million during the quarter after its October 2018 launch. Overall, Biogen estimates more than 170,000 patients in Europe are using one of its biosimilars.

So far, Biogen’s biggest biosim by revenue is Benepali, its version of Amgen’s Enbrel. Benepali has taken the market share lead in five major European markets, CFO Jeffrey Capello said Tuesday. The drug generated $120 million during the period, up slightly from last year’s $116 million.

Meanwhile, Flixabi, the company’s biosimilar to Remicade, grew volume 96% compared with last year’s second quarter, but sales only reached $17 million. 

Biogen is boosting its focus in biosims as it faces patent uncertainty for multiple sclerosis blockbuster Tecfidera and amid new competition for spinal muscular atrophy med Spinraza. The drugmaker also recently suffered a major pipeline setback in Alzheimer's disease, a loss that'll force it to look to new avenues for future growth.

To strengthen its position in biosims, the company last year poured another $700 million into its biosim venture, Samsung Bioepis. At the time, Vounatsos said the company's European revenue was tracking at about $500 million per year, with more biosims in development.

Biogen's effort helps other innovative companies as well, Vounatsos said Tuesday. The discounted drugs help create "financial headroom for innovation in the healthcare system," he said.

In all, the company aims to offer an "improved patient experience at a lower price point," Capello said. A recent study found that 85% of nurses and 78% of patients preferred the Imraldi auto-injector to the Humira device, the CFO said.