Patient Selection for Alemtuzumab for Treatment of MS

Fred D. Lublin, MD: Let’s move on to alemtuzumab. We talked a little bit about this, but Amit, why don’t you take it up.

Amit Bar-Or, MD, FRCP: Alemtuzumab is an anti-CD52, a monoclonal antibody. It depletes fairly broad swaths of immune cells, including B cells and T cells. It’s highly effective at limiting relapse biology, and we did talk a little bit before about the potential for it also to allow you to get off therapy after a couple of cycles, to benefit from a durable control of your disease activity. It has been associated with a rather high frequency of secondary autoimmunity, largely thyroid but not only thyroid. And it’s because of the less common secondary autoimmunity complications that can include life-threatening issues, including platelet disorder or dysfunction or kidney problems, that one needs to monitor this treatment with monthly blood draws for 5 years. So that represents a fairly substantial burden.

And in the last few years, we’ve seen another family, if you like, of complications that seem to be vessel related with a mechanism that is not entirely clear, but this is including dissections, and strokes, and others, which have been associated with fairly high morbidity and even mortality. So that has taken away some of the enthusiasm over using it, at least early on, but it is still available in the armamentarium for patients who haven’t responded sufficiently to other treatments.

Fred D. Lublin, MD: Do you think it has an advantage over either CD20 inhibitors or natalizumab?

Amit Bar-Or, MD, FRCP: It depends what you mean by advantage. From an efficacy standpoint, it has clearly very high efficacy and without a head-to-head, it’s going to be difficult to see whether one is superior to the other. But in terms of the burden, the baggage, and the risks associated at least with the first epoch of treatment, the anti-CD20s and natalizumab in people who aren’t infected with a JC [John Cunningham] virus, the risks are really quite low, at least for several years of treatment.

Fred D. Lublin, MD: That may get into the group that you were talking about, the 1 to 1000, that there may be some who say, as you alluded to, “Well, if I take this for a couple of years, maybe I could stop.”

Amit Bar-Or, MD, FRCP: Exactly.

Patricia K. Coyle, MD: They have very interesting data out to 10 years that indicate maybe more than 50% have normalized their brain volume, and really lowered their neurofilament light protein. That’s intriguing to have treatment just in your first 2 years and then 8, 9, 10 years later, apparently normal brain volume loss and normal neurofilament light protein, if that’s actual. But they have presented some data that would be intriguing if they are accurate.