Pharmacy experts detail their decision-making processes while selecting treatment for myeloproliferative neoplasms and monitoring patients on therapy.
Ryan Haumschild, PharmD, MS, MBA: As we continue our discussion around quality care for patients with MPNs [myeloproliferative neoplasms], one of the things we always have to know is when to start and when to discontinue treatment. We’ve talked a little about pathway-driven and personalized care, but talk to me a little about when you’re on the team and you’re treating a patient with an MPN. When do you want to start or discontinue treatment? What are some of those evaluation timetables that you look at during that continuum of care?
Jeff A. Gilreath, PharmD: Great question. For all of our patients with MPNs, we invite them back to the clinic every 3 months, so we have fairly close follow-up. These things can evolve over time. We don’t just treat laboratory values, we want to treat the patient. It’s typically the symptoms that bring them in, sometimes it’s the routine elevation in white blood cell count, red blood cell count, or platelets, but oftentimes it’s symptoms.
In terms of starting treatment, it depends on what subtype of MPN we’re dealing with. It’s obviously very important to rule out other causes for elevated counts as well. We get a lot of referrals to our center for polycythemia vera, but it may be due to testosterone or other agents causing these counts to elevate. Likewise, we get patients with iron deficiency anemia with thrombocytosis. We get these referrals where it’s not ET [essential thrombocythemia], it’s iron deficiency anemia. We treat them with IV [intravenous] iron, and the platelet count goes down to normal.
In terms of starting treatment, we need the full diagnostic work-up before we even consider. Then we want to take a careful approach to treating patients, making sure that we’re defining what symptoms they have and then targeting those symptoms, at the same time reducing the risk for thromboses. It’s going to depend on whether you have myelofibrosis, polycythemia vera, or ET. If you’re otherwise asymptomatic, it isn’t always wrong to watch the patient for several months and then bring them back. They can always call or come in earlier to discuss whether starting treatment is appropriate.
Conversely, when we discontinue treatment, there are several reasons. There may be adverse effects to the agent. That’s a pretty clear indication to either modify the dose or switch agents when needed. What becomes less clear in patients with myelofibrosis is whether their counts are going up or down due to a toxicity of the drug causing cytopenia, or if we’re seeing transformation and the disease is worsening. Sometimes it’s difficult to tease that out. We need other markers, such as splenomegaly, or other signs of the disease burden getting worse. We’ll take all of these things into consideration when discontinuing treatment or switching therapy.
Ryan Haumschild, PharmD, MS, MBA: That’s great. Having some type of monitoring system is so important, along with having measures of success saying, “This patient is performing well,” or “It’s time we start to evaluate that next therapy. How do we make sure we educate and prepare that patient?” And then we move them on to the next portion of their journey.
Transcripts edited for clarity.