If approved by the FDA, Roche’s Ocrevus would compete with market mainstays — Biogen’s Tecfidera and Tysabri, Novartis’ Gilenya, and Sanofi’s Lemtrada. 

In the neurology category, Roche’s Ocrevus (ocrelizumab) might prove to be the Next Big Thing. The CD20 antagonist is positioned to fill a market gap in primary progressive multiple sclerosis and is also on track to challenge approved treatments for relapsing remitting MS. Why does this matter? Primary progressive MS represents just 10% of patient cases, but relapsing remitting MS accounts for about 85% of cases.

“Ocrelizumab is going to make a splash in MS,” predicts Leslie Sandberg Orne, senior partner at Trinity Partners. The most important driver of the excitement, she explains, is the positive data in primary progressive MS — a variant that hasn’t seen a successful clinical trial or FDA approval. Reports forecast peak sales in the $2.6 billion to $3.8 billion range.

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GSW associate medical director Amanda Luciano says MS therapies typically fall into two categories: safe but questionable with low efficacy or strong but dangerous. However, Ocrevus could be the first product to play between those extremes.

Ramping up for an FDA green light, Ocrevus has market mainstays — Biogen’s Tecfidera and Tysabri, Novartis’ Gilenya, and Sanofi’s Lemtrada — thinking twice. The MS treatment is designed to target CD20-positive B cells, a specific type of immune cell thought to be a key contributor to myelin and axonal damage, a common form of disability in MS patients.

According to Lee Fraser, SVP and group director at Digitas Health LifeBrands, Roche has done a good job explaining why specifically targeting B cells might be the right way to hit the immune system. However, he adds, “Specificity in immunosuppression is not a new story or one that Roche can own entirely, because agents like Lemtrada also provide selective lymphocyte depletion in their own way and might have more compelling molecular rationale and dosing regimens.”

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Roche is attempting to position ocrelizumab ahead of high-efficacy treatments like Tysabri in the treatment sequence and potentially bite into the market share of ABCR treatments.“While reasonable, it’ll likely take compelling initial data combined with a few years of safety experience and additional data in market before earlier use becomes common,” Fraser explains.

Luciano believes ocrelizumab should appeal to HCPs who want to push a patient to a more efficacious therapy after first-line treatment drops off, as well as to entice patients who have resisted progressing to a stronger medication back onto therapy.

Whether or not Ocrevus claws its way to the top, physicians and MS patients believe ocrelizumab will prove a welcome addition to the treatment armamentarium. On top of a strong efficacy profile, the twice-annual infusions will likely be an attractive option for patients accustomed to weekly injections or daily pills.