The Patient on ERT
Medscape: Elosulfase alfa is administered in an infusion center. What is the role of the primary care clinician whose patient is receiving this drug? Is there any monitoring that might need to be done between infusions?
Dr. Pariser: Certainly these patients are cared for, and their care is overseen, by a small number of specialists who are often geographically dispersed. However, there are situations where, if a family lives a long distance from a major teaching hospital or expert center, the every-2-weeks infusions may be given at a local infusion center. In those cases, the primary care provider might be working in collaboration with the specialist.
Dr. Mulberg: No special monitoring is recommended in the elosulfase alfa labeling. Particular concerns still under study with respect to elosulfase alfa are related to the development of antibodies that may affect safety and efficacy, and this is being explored with further studies by the company.
Medscape: What other safety concerns do clinicians need to be aware of?
Dr. Mulberg: Like all of the ERTs, there is a black box warning for development of allergic reactions and hypersensitivity reactions. This is significantly higher in this population than in others. It's hard to know what that means at this early stage. Life-threatening anaphylactic reactions have occurred in some patients during elosulfase alfa infusions. Anaphylaxis, which can present as cough, erythema, throat tightness, urticaria, flushing, cyanosis, hypotension, rash, dyspnea, chest discomfort, and/or gastrointestinal symptoms in conjunction with urticaria, has been reported to occur during infusions, regardless of duration of the course of treatment. Patients should be closely observed during and after elosulfase alfa administration, and clinicians should be prepared to manage anaphylaxis. Inform patients of the signs and symptoms of anaphylaxis and have them seek immediate medical care should symptoms occur. Patients with acute respiratory illness may be at risk for serious acute exacerbation of their respiratory compromise as a result of hypersensitivity reactions and require additional monitoring.
Medscape: Do you have any other messages for primary care clinicians who are taking care of patients who have (or might have) rare diseases?
Dr. Pariser: First, patients with rare diseases need general medical care just like everyone else. Many of these patients are children, and they need vaccines and well-child checks like all children.
Another extremely important role of the primary care physician is to be alert to a potential rare disease in a patient. There was a recent study in the Journal of Rare Disorders in which they surveyed patients with rare diseases and found that they saw an average of 7.3 physicians before a diagnosis was made. Patients expressed strong agreement that primary care physicians should receive additional training in rare diseases. The physicians echoed that; most physicians in this survey (70%) believed that it would be helpful to receive additional training in rare diseases, so it is important for primary care clinicians to increase their awareness of rare diseases. It doesn't mean they have to know everything about every disease -- there are too many of them for that -- but they should be able to recognize patterns, escalate and refer rapidly, and realize that patients will be coming back to them at some point to continue primary care.