What are the best available options for patients with CIDP, and what is still missing?
Jeffrey Allen, MD, an assistant professor of neurology at the University of Minnesota Medical School
Jeffrey Allen, MD
The current state of chronic inflammatory demyelinating polyneuropathy (CIDP) care is, with all things considered, in a good place. With the current options, physicians treating the rare condition are generally able to manage the syndrome effectively.
Although, that does not mean that there is no room for growth, according to Jeffrey Allen, MD, an assistant professor of neurology at the University of Minnesota Medical School. “It’s always a benefit and a desire to make whatever treatments we give to a patient easier on them, more convenient for them, and more tolerated,” he said. One of those improvements has been the development of a subcutaneous formulation of intravenous immunoglobin (IVIG), which has provided patients with an at-home option for treatment.
To provide some additional insight into the current landscape of treatment for CIDP and what still needs to happen to improve the current situation, Allen spoke with NeurologyLive about the condition.
Well, the data tells us that what works is IVIG, corticosteroids, or plasma exchange—that’s the first-line therapies. Most of us would reserve, not consider, plasma exchange first-line for most patients because of the adverse effects and inconvenience that go along with that and the need to get the plasma exchange, repetitively, over a long time is not a great long-term feasible plan. Really, for most patients, it’s either corticosteroids or IVIG as a first-line therapy.
Hizentra is subcutaneous IG, so it’s essentially the same thing as IVIG, but administered subcutaneously instead of intravenously. There was a recent study called the PATH study that was published earlier this year. It’s the largest CIDP randomized clinical trial to date, and a very massive undertaking, that showed that subcutaneous IG is safe and effective for the maintenance therapy for CIDP. The study did not look at treatment-näive patients, so we don’t know what role it has there. I’ve used it, and some patients like it. It’s got certain advantages over IVIG, but it’s not for everybody.
One of the advantages of subcutaneous IgG is that it’s subcutaneous and so instead of relying on a nurse or somebody else who to administer that IV. The subcutaneous IG can be administered by patients at their home. There’s no longer any need to go to infusion clinics or infusion centers, or to be bound by certain dates every 3 or 4 weeks, so there is a lot of flexibility for patients.
Some patients experience adverse effects with IVIG, headache probably being the most common. Those getting subcutaneous IG can still potentially experience those types of adverse effects, but generally, they’re less frequent and less severe, speaking mainly of the headaches.
The other main sort of benefit from subcutaneous is that a lot of patients that are on very chronic IVIG therapy have developed difficulties with intravenous access and may need some other vascular route. With subcutaneous, that problem goes away.
On the other side of that, some patients just don’t like that, in order to get subcutaneous, generally, we give it much more frequently than IV—for most patients, that means once or twice a week, with a needle that the patient has to place in their subcutaneous tissue. Some patients just don’t like needles and that whole process of opening themselves for subcutaneous infusion once or twice a week is not desirable to them.
The focus on development is on finding new approaches to treat the disease that are safe and can create a situation where a patient has less immunologic activity and is working towards a remission state.
One challenge in a disease like CDIP, where there’s no biomarker to tell us whether a disease is active or not, is our treatments are generally long-term treatments—some of them are quite extensive. We really want to know, therefore, is if we’re using these treatments and we’re exposing our patients to potential risk, that they’re working and they’re doing what we hope they do. That means making the neuropathy better.
We know from the multiple randomized clinical trials out there that have been conducted for CIDP now, with several different agents, that overtreatment of CIDP is common. One of the challenges of the whole treatment landscape is still understanding if our treatments are working, measuring that response, and if they’re working, understanding what the optimal dose of steroids is or the optimal dose or frequency of IVIG is. Sort of tailoring a treatment to an individual patient.
Then, over the long term, continuing to address the possibility that maybe that drug isn’t needed anymore. That can be a difficult thing to sort out without really pulling back on the drug and monitoring it closely. Really the main challenge is how do we optimize treatment, personalize treatment, and know if we still need treatment.
Transcript edited for clarity.