The late August approval of Tyruko (natalizumab-sztn) by the U.S. Food and Drug Administration (FDA) is big news in the multiple sclerosis (MS) world. Tyruko is a biosimilar for Tysabri (natalizumab), and it's the first biosimilar to gain FDA approval as an MS disease-modifying therapy (DMT). "Tyruko has the potential to extend the reach of natalizumab treatment for [MS] patients, increase healthcare savings and fuel innovation through competition in the market,” Keren Haruvi, president North America of Sandoz Inc., said in a press release. Bari Talente, executive vice president for advocacy and healthcare access at the National Multiple Sclerosis Society, calls it a "milestone" and says it can "increase accessibility to affordable medications, improve adherence and help contain healthcare costs.” What's a biosimilar? A biosimilar, as the name suggests, is similar to an approved drug in terms of quality, efficacy, and safety. It's typically available at a lower cost than the original medication. But a biosimilar isn't the same as a generic. Generics are meant to replace simple medications that are made from chemicals. Their active ingredient is identical to the brand-name product, but they may contain different inactive ingredients, such as preservatives. Biosimilars replace more complex medications that are made from living cells. But because the manufacturing process of the original medication is proprietary, a biosimilar's production process is always slightly different from the original. Generics usually cost much less than the original drug because their manufacturing process is simple. Biosimilars are somewhat less expensive than the original, but the price difference isn't as dramatic as it is with generics because biologics' structure and production processes are more complex. Can biosimilars really reduce cost? The National Multiple Sclerosis Society's website reports the median annual cost of an MS DMT last year was around $94,000. Six DMTs have increased in price more than 200% since 2009. A survey of 21 biosimilars, taken in 2021 by Stat, reports that biosimilars were an average of 30% less expensive than the original drugs. A 2020 study by Johns Hopkins University reported that patients who were prescribed a biosimilar infusion used to treat Crohn's disease paid an average 12% less (about $300 each year) out-of-pocket for that medication. The FDA's website says that because biosimilars cost less, they may also be covered by more insurance plans. I was treated with Tysabri for about seven years and was fortunate that its cost was totally covered by Medicare plus my Medicare-gap commercial insurance. But not everyone is as lucky. It's not unusual for me to read, on the MS News Today Facebook page and elsewhere, about people who have a hard time affording their MS treatments. Sometimes people even skip treatments because they can't pay for them. Let's hope that other biosimilars will follow Tyruko into the MS medication market. As Talente said, they should "increase accessibility ... improve adherence and help contain healthcare costs.” That's a very good and necessary thing. You're invited to visit my personal blog at www.themswire.com. Note: Multiple Sclerosis News Today is strictly a news and information website about the disease. It does not provide medical advice, diagnosis, or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The opinions expressed in this column are not those of Multiple Sclerosis News Today or its parent company, BioNews, and are intended to spark discussion about issues pertaining to multiple sclerosis.