A CME/CE-CERTIFIED WEBCOURSE Program Transcript Program Steering Committee/Faculty: ELIAS ANAISSIE, MD Medical Director, CTI Clinical Trial and Consulting Services Associate, Metropolitan Infectious Diseases Houston, TX JOSEPH BUBALO, PharmD, BCPS, BCOP Oncology Clinical Pharmacy Specialist Assistant Professor of Medicine Oregon Health and Science University Hospital and Clinics Portland, OR Jointly provided by Potomac Center for Medical Education and Rockpointe This program is supported by an educational grant from Merck.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 2 Slide 1 Title Slide Joseph Bubalo, PharmD: Welcome to Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem-cell Transplant. Slide 2 Program Faculty Myself, Joseph Bubalo, a Clinical Pharmacist at Oregon Health and Science University Hospital, and Elias Anaissie, a Medical Director and the Clinical Trial Leader, as well as a well-known consultant in infectious disease, who works out of Houston. We ve put together a program today for you to join us in looking at how to best prevent fungal infections in stem-cell and hematologic malignancy patients. Slide 3 Disclosures There are our disclosures. Slide 4 Learning Objectives Our objectives today are at the conclusion of this activity, participants should be able to demonstrate their ability to: 1) discuss the clinical data for current, recently approved, and emerging antifungal agents; evaluate the use of single and combination treatment strategies for fungal infections; and then be able to individualize the management of an invasive fungal infection for patients with that need. And, once again, we re focusing on hematologic malignancies and hematopoietic stem-cell transplants. Slide 5 Case Discsussion: A Patient with AML We re going to have a case which will flow throughout the program, and this is going to be an individual with acute myeloid leukemia (AML). Slide 6 Our Patient Our patient is a 37-year-old male. He is admitted with a diagnosis of AML. He has a white count of 45,000, normal cytogenetics. He s FLT3/ITD (+), NPM-1 (-). And his treatment plan, once he s been diagnosed, is going to be a standard induction. And since he s FLT3 (+), he ll actually go on for an allogeneic hematopoietic stem-cell transplant for the cure. As we look at this, 1) what is your risk assessment for this patient when you think about fungal disease, and would you start antifungal prophylaxis now? Dr. Anaissie, could you take it from here, please? Slide 7 Risk Factors for Invasive Fungal Disease (IFD) in Patients with AML Elias Anaissie, MD: Thank you, Dr. Bubalo. I will be going over the risk factors for invasive fungal disease, first, in patients with acute myelogenous leukemia and, subsequently, as this
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 3 patient undergoes clinical hematopoietic stem-cell transplant, allogeneic; we ll discuss those, as well, breaking them down into pre-engraftment and post-engraftment risk factors. Slide 8 Incidence of IFD in Hematologic Patients You see the incidence of invasive fungal disease in patients with hematologic cancers. As you could see, acute leukemia, both AML and ALL, have the highest risks, more so acute myelogenous leukemia and significantly less in the case of chronic myelogenous leukemia, particularly since the introduction of tyrosine kinase inhibitors and other hematologic conditions. Slide 9 Factors Influencing the Risk of IFD in AML The factors that influence the risk of invasive fungal disease in AML, are very few. One, the single most important one, is the duration of severe neutropenia, severe meaning less than 100. And the duration, typically, is more than 10 to 14 days. This would represent the highest risk. We go first by the risk of AML itself. Is it a high-risk AML, intermediate-, or low-risk? And, by that, we mean the likelihood of the patient achieving complete remission; that would be the lower risk because they do have the higher likelihood of achieving complete remission and, therefore, shorter duration of neutropenia since the complete remission is defined, among others, by the fact that absolute neutrophil count has returned to more than 1,000, etcetera. While there are well-known risk factors older age; white blood cell count about 50,000; and, most importantly, the cytogenetic and molecular profile on their bone marrow aspirates and biopsy. Essentially, they now drive how we treat acute myelogenous leukemia. And certainly, also, a second risk factor impacting the duration of neutropenia is the fact and intensity for remission induction chemotherapy, which, for example, high-dose cytarabine, has a higher risk than this conventional 7+3. The presence of comorbidities is also extremely important; that would include the former status of the patient, the functional capacity, if limited for example, activities of daily living and others and the presence of mucositis and other organ dysfunctions, particularly pulmonary dysfunction and a history of smoking; others include hyperglycemia, if it s sustained and controlled, and, most likely, the presence of genetic polymorphisms that increase the risk of certain invasive fungal infections, particularly aspergillosis. Slide 10 Factors Influencing the Risk of IFD in AML On this slide, you will see the additional risks, which is, foremost, environmental exposures, and that applies to individuals who have jobs in which they are likely to be exposed to a lot of airborne molds, such as: construction work, farming, gardening, working in a florist shop, and forestry work. And during hospitalization, they need to have a room with a HEPA filter, avoiding, when possible creating good barrier when the hospital is undergoing building construction and renovation, which is almost always the case, and, certainly, the water leakage on the hospital s ward. There is also the local epidemiology that helps us understand what kind of infections we re dealing with, and whether or not we use antifungal prophylaxis in the class of agents, meaning does it cover yeast only, like Candida, or both yeast and molds, for example, aspergillosis. Slide 11 Defining Risks: Yeast vs Mold Infections In this slide, the difference between the risk factors that are more specific, yeast and/or for molds. Neutropenia is certainly important for both; although, more prolonged neutropenia tends to be associated with invasive mold infections, hyperglycemia, and immunogenetics for both because that typically has to do with yeast infection and Candida because of the presence in
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 4 the gastrointestinal tract of a large number of Candida species, especially in patients who have received antibiotics as AML patients do. Intravenous catheters, again, mostly for yeast, while environmental exposure, the presence of T-cell immunodeficiency and iron overload along with respiratory viral disease immediately preceding remission induction or during it tend to put the patient at higher risk for invasive mold infections. Slide 12 Risk Stratification for Defining Antifungal Prophylaxis in Patients with AML This is, in a summary, the risk stratification for defining the type of antifungal prophylaxis that one is to use in patients with acute myelogenous leukemia. We re looking, as you can tell here, three columns: low, intermediate, or high. And, in the left column, you have the actual factors, so: older age will put the patient at higher risk, as well as the type of leukemia is it de novo, or newly diagnosed, or is it the leukemia that is treatment-related or secondary AML, and relapsed/refractory. The types of cytogenetics are important, as well, because they could be favorable, such as translocation (8, 21), inversion (16); intermediate such as normal cytogenetics; or high when you have other abnormalities such as complex cytogenetic. The gene mutation profile is becoming more important, particularly when it relates to NPM1 and FLT3/ITd, the latter being associated with the higher risk, while the presence of mutated NPM1, along with mutation of CEBPA, would be associated, would confer a lower risk for invasive fungal disease, all of this related, again, to the duration of neutropenia. White blood cell count is consistently being shown to confer a higher risk of leukemia, meaning a lower risk of achieving complete remission, and the higher the count is, the lower the ability of achieving complete remission, therefore early recovery from neutropenia. As I mentioned earlier, the presence of HEPA filter, comorbidities are very important, particularly as far as invasive mold infections are concerned. And a history of prior mold disease rarely but sometimes they do, patients with AML may present, actually, with invasive aspergillosis. Some of these become very important in terms of our decision to certify patients for risk of invasive fungal disease following an initial induction chemotherapy, and, hence, the plan for what kind of antifungal agent class, activity, etcetera we would be using. Slide 13 Discussion Question To illustrate this point, here is a question in regard to this patient: You can see the patient is young; he has de novo leukemia both good risk factors. He has intermediate risk factor of cytogenetics was normal. And white blood cell count is not higher than 50,000, so, again, not high-risk. On the other hand, he is FLT3/ITD(+), NPM1(-), putting him at high risk for low neutropenia and, therefore, high risk for an invasive antifungal disease. In addition, as I mentioned earlier, environmental exposure, whether there s a HEPA filter or not, the presence of comorbidities and prior mold disease. You can see here the risk factors, how would you assess this patient s risk for invasive fungal disease in this setting? Dr. Bubalo, would you like to comment on this question? Slide 14 Answer Joseph Bubalo, PharmD: It seems to me that a good risk, when we think about he s young, he s 37, he s a de novo, he s not a secondary leukemia, he s got the high white count. But, really, that FLT3 trumps everything else; that s going to make him a high-risk candidate, as I read it.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 5 Elias Anaissie, MD: This certainly makes sense. Slide 15 Defining a Prophylactic Strategy for IFD Here s what we would recommend as a prophylactic antifungal strategy: In the patients at low risk for invasive fungal disease, certainly, we do not need any prophylaxis, as this patient is likely to have a short risk of neutropenia, likely to achieve complete remission rather fast, and we can just monitor. Now, as the patient s main risk is candidiasis based on the fact that the regimen we are using is likely to cause gastrointestinal mucositis, i.e. candidiasis, therefore, fluconazole alone is a very reasonable strategy. On the other hand, if we have a higher risk for candidiasis and/or particularly mold disease, then we have two strategies which one we pick depends a lot on what resources are available to us. One approach I always follow is to use fluconazole along with active monitoring, and that implies two to three times-weekly serum aspergillus galactomannan antigen and, clinically, based on, say, persistent fever, a high-resolution CT scan of the chest. Now, I ll initiate more active therapy from those as soon as I have evidence of infection. On the other hand, many centers do not have access to timely resulting of aspiration of galactomannan, in which case it would be preferable to start up front in the high-risk population with a more active antifungal azole. Slide 16 Anti-mold Prophylaxis in AML For example, the use of posaconazole, the agent that is approved now by the FDA for antifungal prophylaxis in patients with acute myelogenous leukemia. This slide by Cornely et al. in New England Journal of Medicine, 2007, indicated that this drug, as compared to fluconazole and/or itraconazole in a large, randomized controlled trial, multicenter, multinational, that, in fact, posaconazole does reduce the incidence of invasive fungal infections, including invasive aspergillosis, with a significant effect on death due to invasive fungal disease. Slide 17 Anti-mold Prophylaxis in AML This would be the agent I would use if I did not have access to rapid resulting of a specialty serum aspergillus galactomannan. And, as you can see on this slide, in fact in this very same results, is the lower-risk probability of death in green for patients who were placed on posaconazole prophylaxis as compared to those who got either fluconazole or itraconazole. Slide 18 Randomized Trials of Antifungal Prophylaxis in AML/MDS: Effect on Aspergillosis To summarize what is available in the literature so far with regard to antifungal prophylaxis in patients with acute myelogenous leukemia, including only the randomized trials, there are several trials with itraconazole. The bottom line with itraconazole, if you can get the drug in, usually, a solution is much better, but using the capsule cause major issues with bioavailability. In a study using caspofungin vs fluconazole, there was no significant difference in aspergillosis or invasive fungal infections overall. Similarly, when liposomal amphotericin B (L-AmB) intravenously was used every other day, vs no prophylaxis, there was a benefit from inhaled L- AmB vs placebo. As you can see, 14% for patients randomized to placebo, and 4% only for those randomized to inhaled liposomal amphotericin B; however, this formulation, as given, was associated with poor compliance mostly related to respiratory problems. And, lastly, as I mentioned earlier, posaconazole vs fluconazole vs and/or itraconazole did make a difference in terms of aspergillosis as well as in terms of overall survival. Those receiving posaconazole had advantage on both of these endpoints. Slide 19 Back to our Patient
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 6 Let s go back to our patient. Again, we said this is a 37-year-old male, high risk for AML. He did receive induction with 7+3 cytarabine seven days, idarubicin three days. Did receive fluconazole prophylaxis, but because he was at high risk, he did undergo active monitoring three times a week with a specialist serum aspergillus galactomannan. He developed febrile neutropenia, no major complications, no invasive fungal disease, and he recovers on day 24, and he is sent home. Because he is a high-risk acute myelogenous leukemia, this patient has a likelihood of relapsing unless he undergoes an allogeneic stem-cell transplant as a consolidation of his try at complete remission. Slide 20 Second Admission for our Patient: Allogeneic-HSCT As you can see on this slide, basically, donor and the recipient were CMV-positive. The patient received peripheral blood stem cells as opposed to cord blood or bone marrow, and he received a myeloablative conditioning with busulfan and cyclophosphamide. To prevent graft-versus-host disease (GVHD), he was given cyclosporine as well as methotrexate, which is optimal prophylaxis for this condition. Slide 21 Discussion Question This brings us to the second question regarding this patient. After reviewing the data, would you start antifungal prophylaxis yes or no? And, if yes, which agent would you select? Dr. Bubalo, would you like to comment on this question? Slide 22 Answer Joseph Bubalo, PharmD: I look at that and I say no prophylaxis, for it s not a good option given that we re about to ablate the bone marrow. Fluconazole, as we talked about earlier, is a good anti-candidal agent, not so great against filamentous fungi. But if we have availability for aspergillus monitoring with a galactomannan test, then I think that somewhat makes up for it. Posaconazole and voriconazole much broader agents, and the issue there probably is going to be more drug interactions with the immunosuppressants. And, certainly, if we re about it, it would be started during chemotherapy. Micafungin actually, I think, has some data here and could be considered, as well. As we look at the risks in this patient now that they re in the early phase of an allogeneic stemcell transplant, where would you go with that, Dr. Anaissie? Elias Anaissie, MD: Well, what options would include a fluconazole with active monitoring very active, meaning three times a week galactomannan and/or micafungin for that matter, because it s as effective as fluconazole, as you just mentioned, in the game of stem-cell transplant for candidiasis. The role of posaconazole and voriconazole clearly much broader spectrum including invasive mold infections although marked by the issues of drug-drug interactions which we will be discussing down the road. Slide 23 Risks for IFD during the Pre-engraftment Phase of Allogeneic HSCT? To address this question, how well to answer it, I m going to be presenting the risk for invasive fungal disease early after allogeneic stem-cell transplant with the first choice as the preengraftment phase before the patient has engrafted the marrow of his donor and with recovery of, basically, cytopenias.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 7 The factors influencing the incidence of invasive fungal disease during this period are shown on the next slide. Slide 24 Factors Influencing the Incidence of IFD During the Pre-engraftment Phase Certainly, the status of the underlying disease this patient was in complete remission; therefore, he is less likely to be at risk for that particular factor. The stem-cell source cord blood first, then, is typically also shared with very prolonged neutropenia. I would put the patient at the highest risk for neutropenia and, hence, for invasive fungal disease during pre-engraftment. Similarly, the intensity of conditioning regimen in this case here, it was given busulfan and cyclophosphamide at myeloablative doses, and, therefore, that is a high risk as opposed to using a non-myeloablative dose at the other screen, and, in between, a reduced intensity regimen which could include, of course, busulfan but at a lower dose than one used in myeloablative setting. Slide 25 Factors Influencing the Incidence of IFD During the Pre-engraftment Phase Again, like with acute leukemia, with environmental exposure, antifungal prophylaxis and other risk factors are important, and one particular is a new one that is different than in remission induction for his AML, is whether we use an optimal GVHD prophylaxis, and what kind of agent do we use with T-cell depletion would probably increase the risk for T-cell immunodeficiency but certainly reduce the risk for GVHD. Iron overload, genetic polymorphism in innate immunity genes for risk factors for individuals are also somewhat important. And most important, though, is whether the patient did develop invasive mold disease during remission induction; in this case, the patient did not. Slide 26 Effect of the Conditioning Regimen and Stem-cell Source on the Duration of Neutropenia in Allogeneic-HSCT To illustrate the importance of the duration of neutropenia and its severity, as you can see on this slide, you could start by either at the lower end non-myeloablative, non-myelotoxic regimen would give you the lowest risk for invasive fungal disease just because of the low risk short duration of neutropenia while, on the other end, you re dealing with a myeloablative regimen in a patient who received a cord blood as a source of his or her stem cells. And, in between, you could see the non-myeloablative, myeloablative peripheral blood, and the myeloablative bone marrow; all of these gives us a pretty good idea of the expected duration of neutropenia and, hence, allows us a baseline to make a decision as to what kind of antifungal prophylaxis, we would like to provide for these patients. Slide 27 Risk Stratification for Defining Prophylaxis in Allo-HSCT: Pre-engraftment Period And, again, as we ve spoken before in the setting of AML, this is a paper brief showing a risk stratification for the possibility of developing invasive fungal disease. And, again, it s low, intermediate, or high. And, on the left-hand column are the specific factors that confer low, intermediate, or high risk to this patient, which, clearly, the patient being in complete remission is a much lower risk than if a man who has active AML that is not controlled with anti-leukemic therapy. Using a myeloablative regimen is going to give you prolonged longer neutropenia; that would not be the case in non-myeloablative and the same high risk as if one is resorting to cord blood as a source of stem cell because of the fact that cord blood is associated with the longest duration of neutropenia.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 8 As mentioned earlier, the lack of HEPA filtration in the patient s room would be potentially an additional risk factor, as would be the T-cell depletion whether it s done ex vivo or with antithymocyte globulin, again, would cause more immunosuppression, T-cell immunodeficiency, specifically, than would a conventional GVHD prophylaxis like, say, cyclosporine plus or without methotrexate. The presence of comorbidities, again, lung disease, diabetes, respiratory viral infection, etcetera, along with a prior history of invasive mold disease would confer a higher risk for the development of invasive fungal disease, particularly in this case, invasive mold disease. Going back to this particular patient, the only concern we have is he did have myeoloablative conditioning, but all other factors are not present no prior mold disease, no severely T-cell depleting prophylaxis, no significant comorbidities, HEPA filter presence, etcetera, so he would be at a rather lower risk of invasive particularly mold disease during the pre-engraftment phase. Slide 28 Antifungal Prophylaxis in Allogeneic HSCT: Pre-engraftment Period Let s go over what has been examined in clinical trials as far as antifungal prophylaxis during this early pre-engraftment phase. Slide 29 Micafungin vs Fluconazole Prophylaxis in Allo-HSCT This is a study comparing micafungin, an echinocandin to fluconazole for the conventional fungal infection in the setting of other genetic stem-cell transplant during the pre-engraftment phase 50 milligrams per day of micafungin vs 400 milligrams per day of fluconazole until engraftment, and you could see there is a trend, not statistically significant but a trend, of possible protection against aspergillosis. However, for Candida, overall invasive fungal infection there was no significant difference between fluconazole or intravenous micafungin; although fluconazole recipients did have higher risk of using empiric antifungal therapy, which could be not a major but a very well-defined setting. In essence, more micafungin and fluconazole will protect against Candida. Slide 30 Voriconazole vs Fluconazole Prophylaxis in Allo-HSCT In this study, Wingard et al. compared fluconazole, the standard, to voriconazole. However, the study went all the way from conditioning until the 100 or beyond, depending on what was going on with GVHD. And the composite endpoint was that the patient was able to tolerate the drug for 100 days or more and was alive, without invasive fungal disease at the six-month endpoint. As you can see, again, there was a trend, although not statistically significant, at the 0.05 level of reducing aspergillosis among voriconazole recipients as compared to fluconazole recipients. The Aspergillus galactomannan was obtained but was not included as a primary endpoint in this particular trial. Slide 32 Voriconazole vs Itraconazole Prophylaxis in Allo-HSCT Looking now at voriconazole vs itraconazole and in this particular study, there was a benefit of voriconazole in terms of toleration to the 100 or longer, and survival without invasive fungal disease until six months. But tolerability was the key; however, no significant difference with relation to actually developing invasive fungal disease or a survival as the primary endpoint, the composite endpoint without invasive fungal disease. Going on right now with the kind of summary but focusing on aspergillosis, the results are shown on the following slide. Slide 32 Randomized Trials of Antifungal Prophylaxis during Pre-Engraftment Period: Effect on Aspergillosis
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 9 First, is an all allogenic stem-cell transplant the recipients. You could see on the first row the days of prophylaxis mica vs fluconazole with the year of engraftment while voriconazole trials, whether vs fluconazole or itraconazole, continues until day 100 or up to day 180. And, as you can see, none of these trials did appear to show a statistically significant reduction in the cases of invasive aspergillosis, with the number needed to treat at the bottom being rather high. Slide 33 Back to our Patient To go back to our patient as I mentioned earlier, we did not consider him to be at high risk because the only risk factor was the fact that he received myeloablative conditioning, so he received fluconazole prophylaxis and underwent serial three times a week, monitoring with aspergillosis galactomannan. He developed febrile neutropenia, grade 2 oral mucositis; otherwise, no other complication, no invasive fungal disease. Engrafted on day 14, discharged home on day 19 while receiving prophylaxis with fluconazole, valacyclovir, trimethoprimsulfamethoxazole, and cyclosporine for his GVHD. Slide 34 Allo-HSCT, Day +45 Post Transplant With day 45 from the infusion of his stem cells, now he is presenting with significant diarrhea, seven bowel movements that are watery for 24 hours, along with colicky abdominal pain and for which he is, of course, hospitalized. On exam, there is a typical generalized erythroderma of GVHD. The lab values for hemoglobin, white blood cell, platelets are shown here. Nothing got shaken except that he did have increase in AST in his liver function, cause his AST, and his bilirubin was slightly elevated, as well. Of course, one has to exclude other causes for abdominal pain; they were excluded. And based on the combination of typical generalized erythroderma and the abdominal pain, diarrhea, and lack of other causes that could account for the stem-cell presentation, a diagnosis of acute GVHD was made, and the patient was started on prednisone 2 milligram per kilogram per day, the standard dose for treatment of acute GVHD. Slide 35 Discussion Question Now what do we do? Do we change antifungal prophylaxis? Do we keep it the same but switch to intravenous posaconazole? Or do we switch the patient s from fluconazole to voriconazole? Dr. Bubalo, would you like to comment on this question? Joseph Bubalo, PharmD: I don t think I m comfortable staying with just the fluconazole with monitoring. We would generally go to something, a broader agent. The IV posa followed by a new oral formulation of tablets is certainly a possibility and could be done, or you could go to voriconazole. I think, given his labs on the prior slide and the elevated bilirubin, I would probably choose posaconazole over voriconazole from a potential toxicity standpoint. Slide 36 Answer Elias Anaissie, MD: A very good point. Exactly, I agree. This is what we did with this patient, because we do have intravenous posaconazole which allows us to start it. And once his gastrointestinal GVHD is controlled, we no longer have any concerns about the status of his gastrointestinal tract. It would be intact and should be able to absorb posaconazole already rather well, and we would do that. Slide 37 Timeline and Risk Factors for IFD in Allo-HSCT And, as a follow-up, just contrasting pre-engraftment vs post-engraftment, the biggest issue with the post-engraftment is CMV reactivation and the presence of severe grade 4 acute and/or chronic is the definition now is different than day 100 GVHD. There is another risk during the engraftment. As we mentioned earlier, gastrointestinal because that has the menace of candidiasis associated with it.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 10 Slide 38 Most IFDs in Allo-HSCT Occur After Engraftment And, in the recent study looking nationwide, 23 different centers in the United States, the invasive fungal disease among stem-cell transplant recipients this slide shows the time to invasive fungal disease. And what this shows is that, most like because of prophylaxis, we don t see Candida much anymore early on, but you would see that the other infections tend to occur post-engraftment, basically, day 180, etc. Just a point to keep in mind that we should not just focus on neutropenia pre-engraftment. In this setting and during AML remission induction, we have to maintain vigilance for the risk of invasive fungal disease during the post-engraftment phase. Slide 39 Factors Influencing the Incidence of IFD During the Post-engraftment Phase This slide shows the factors influencing the risk during post-engraftment. Certainly GVHD comes to mind, I think the most important one, because you re going to be using high-dose corticosteroids; sometimes, you may have to add more if the patient fails to respond to corticosteroids of his GVHD, then we d have a problem because it goes downhill from there. And the activation of cytomegalovirus infections is important because it is a cause of neutropenia, as well as overtreating with ganciclovir, which, by itself, can cause neutropenia, the presence of graft failure, again, related to the same issue of neutropenia, as well as the other classic risk factors that I ve mentioned during pre-engraftment as well as during remission induction therapy for AML, and that is below environmental exposure to molds, influenza with significant clinical numbers like that during this phase if we use fluconazole as opposed to posaconazole in someone getting corticosteroids for GVHD and possibly also the role of genetic polymorphisms and iron overloads. Slide 40 Factors Influencing the Incidence of IFD During the Post-engraftment Phase When should we be concerned about post-engraftment invasive mold disease? We re just focusing now on mold, only taking Candida out of the picture because it has typically more likely to cause a problem. Certainly, GVHD, especially if it s not responding well to corticosteroids; neutropenia, prolonged, regardless of the cause; and CMV reactivation, not just because of neutropenia but because cytomegalovirus in this setting does have an immuno-relating factor where is also an effect on T-cell-mediated immunity. So these would be the biggest risk factors for invasive mold infections such as aspergillosis in this setting, i.e. post-engraftment. Slide 41 Posaconazole vs Fluconazole in Allo-HSCT Recipients Has this been studied before? OK, I m showing you now the results of this study by Ullmann et al. comparing fluconazole vs posaconazole prophylaxis among this patient population. It was a double-blind placebo-controlled multicenter, multinational trial. Patients with acute GVHD, severe, meaning grade II to IV, or chronic extensive GVHD were receiving corticosteroids with or without other immunosuppressants. The posaconazole formulation used the oral suspension, 200 milligrams three times a day vs fluconazole 400 milligrams once a day, and the primary endpoint was proven and probable invasive fungal disease from day of randomization until day 112 of antifungal prophylaxis. And the results are shown in the following slides. Slide 42 Posaconazole vs Fluconazole in Allo-HSCT Recipients Roughly 300 patients in each arm. The proportion of patients who have probable or proven invasive fungal disease was significant for aspergillosis. As you can see, 7% vs 2% with a P- value of 0.006. And when looked at the during prophylaxis, which was the secondary endpoint, again, whether it was total invasive fungal disease or invasive mold disease in the form of
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 11 aspergillosis, posaconazole did confer protection to posaconazole recipients who did have severe, grade II to IV GVHD. Slide 43 Posaconazole vs Fluconazole in Allo-HSCT Recipients This slides gives us an idea of the time to proven or probable invasive fungal disease. On the left-hand column, you see the probability of onset of infection. And then, on the bottom, you see the days after the study is over, and you could see it is a statistically significant posaconazole does reduce the incidence in the time to invasive fungal disease. Slide 44 Back to our Patient Going back to our patient now, the patient was continued on the antifungal prophylaxis fluconazole with serum aspergillus galactomannan three times a week because we felt that we do get the results within 12 to 24 hours, and we do quickly perform a CT scan of the chest, highresolution, in the event that they get galactomannan and it turns positive. On day 60, that is, after two weeks of corticosteroids for GVHD, he got much better. The rash resolved, diarrhea improved, but the liver enzymes remained somewhat high. He did have evidence of CMV reactivation and, thus, ganciclovir IV was started. Four days later, he started complaining of a dry cough and a left chest pain, and the serum galactomannan index, which is normal if it s less than 0.5, is now positive at 0.44. Slide 45 Chest CT scan We do a high resolution CT scan of the chest, and this is what we get non-specific lung infiltrates. Now, typically, we are always reminded of the infarct-like picture, the halo sign, and others infiltrates typically associated with invasive aspergillosis. The reality is this happens most typically in patients with acute myelogenous leukemia. In patients who have deficient T-cellmediated immunity, they can present as non-specific lung infiltrates such as in this patient. Slide 46 Back to our Patient This should not be disregarded as not being invasive mold disease or invasive aspergillosis, particularly in the setting of a repeatedly positive galactomannan in a patient like this, and, therefore, BAL is performed, the diagnosis further confirmed by presence of a positive galactomannan from the lavage fluid of 3.66; although, the cultures and direct exam were negative, as expected and, therefore, the diagnosis of invasive aspergillosis is made. Slide 47 Discsusion Question Going back to question here, what would be your first choice for treating invasive aspergillosis in this patient? Dr. Bubalo, would you like to comment on this question? Slide 48 Answer Joseph Bubalo, PharmD: If I look at this, liposomal amphotericin B is the mainstay for therapy for many years, but the concern has always been the toxicity, and could we find something that was less toxic. But voriconazole and isavuconazole, along with a decreasing immunosuppression would be vori and isavu are both actives. If we can trim off the immunosuppression that would be in this patient s benefit. The echinocandins generally are more aspergillus-static as opposed to really clearing the infection, so we don t usually treat with those. Posaconazole has really good prophylaxis data, but I don t know that it has good treatment data. And then the combination therapy, I think, is still considered somewhat experimental. How do you feel about those? Elias Anaissie, MD: I concur. I think, right now, the data for treatment exists with voriconazole and with isavuconazole. And, of course, any time we can, with setting of invasive aspergillosis,
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 12 we also decrease immunosuppressant. Again, that s sometimes frequently easier said than doable. Slide 49 Treatment of Invasive Aspergillosis If we look a little bit of a summary in this slide, primary therapy of invasive aspergillosis is the first trial with voriconazole that randomized patients to vori vs amphotericin B, deoxycholate. Certainly, you have your higher response rate and improved survival. With isavuconazole, there was randomized trial isa vs vori and similar response rate and fewer side effects with isavuconazole just recently published by Maertens et al. in The Lancet. Now, for liposomal amphotericin B, it is an option, but the toxicity can be quite significant. And I would not go beyond the 3 milligram per kilogram per day. As you can see from this trial by Cornely, there was no difference except for higher toxicity when the dose was escalated to 10 milligram per kilogram per day in the randomized controlled trials. To repeat, essentially, it s voriconazole and isavuconazole that would be the first option in this particular patient. Slide 50 Back to our Patient If we go back to our patients, we have a diagnosis of invasive aspergillosis. We started intravenous voriconazole, loading dose, as always, followed by maintenance dose. And we looked at the serum aspergillus galactomannan, and it is still positive, actually going up. That may be worthy of your concern. What do you think? Slide 51 Discussion Question Here s the question: What is your interpretation of these competing values of serum aspergillus galactomannan: no issue is it expected that it would increase during the first week of therapy; or is this truly failure of voriconazole as antifungal therapy; or we have a false positive galactomannan in the context of GVHD in the area; or, quite frankly, if we don t know, I m not sure? Dr. Bubalo, would you like to comment on this question? Slide 52 Answer Joseph Bubalo, PharmD: Now, clinically, we see this, and it is an ongoing debate since the galactomannan is part of the fungal cell wall, whether this doesn t represent clinical response to this therapy. I know there is some literature out there that suggests that and it s just case reports that it does go up with therapy but it s unclear. I don t know. Do you have other data? Slide 53 Increasing Serum Galactomannan Levels Indicates Therapeutic Failure Until Proven Otherwise Elias Anaissie, MD: Yeah, there are several data now that show that persistence of aspergillus galactomannan is associated with failure, specifically with death. We have three papers from our group in 2007 and 2008; there is this paper in 2012, also, from our group as an idea of survival. There is also data, also, by Maertens in Cancer, in 2008, confirming our findings, that persistence of aspergillus galactomannan elevation essentially means treatment failure. Again, for example, you could see the survivals between those patients whose galactomannan normalized within seven days vs those who normally took longer than seven days to normalize. Slide 54 Causes of Antifungal Therapy Failure The data of failure of antifungal therapy, what is this due to? Certainly, one has to think about host factors, and that s the most common one. If the patient is persistently neutropenic, for example, in the setting of AML remission induction, failure to recover a reasonably good ANC maybe 500 to 750 is almost always associated with progressive aspergillosis because to control you want in terms of antifungal therapy immunity remains an optional key to factors.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 13 Occasionally, its primary drug resistance, meaning the organism that s infecting this patient is not susceptible to the activity of the antifungal used; or we have to think of maybe the wrong diagnosis or a mixed infection, so that these patients are probably immunosuppressed. They could have aspergillosis along with Legionnaires disease or with whatever else infection you could consider. The drug toxicity is a possibility in the lungs, but that is highly unusual with these agents. Development of resistance is rather unusual in this setting, so I would say, most importantly, in this particular setting, I would focus on host factors and the presence of mixed infection if, radiologically, there is evidence of progressive lung infection. We ve shown, though, earlier on that there is something called the immune reconstitution inflammatory syndrome, which we have shown in patients with invasive aspergillosis, where patients galactomannan goes down, the C-reactive protein goes down, the count is going up at the same time, and, all of the sudden, the patient s invasive disease shows up. It s exactly the same as being described in patients with AIDS upon immune reconstitution of their CD4 counts. Now, last but not least is, are we giving enough of the drug? Is there any drug-drug interaction that would decrease the the exposure to this particular antifungal in patients? Slide 55 Possible Actions for our Patient And what is it we can do now? For persistent immunosuppression, if possible, if GVHD is very well controlled, we could either reduce immunosuppressant or use a steroid-sparing agent. If we re concerned about mixed infection, like I said early, follow up on results of the bronchoalveolar lavage, obtain other testing, PCR for viruses. And if there is no cultivation of the drug, we have to do, first, simple stuff which is maybe drug-food or drug-drug interaction. And is the level of the drug good enough for this particular patient may be challenging to decide whether it s tissue level or serum level. We have cut-off points that would indicate that lower levels are associated with failure and higher serum levels of even the anti fungal agents are associated with success, which brings us to where Dr. Bubalo would be the more qualified colleague to discuss. Dr. Bubalo, would you like to take over at this point? Joseph Bubalo, PharmD: Yes, thank you very much, Dr. Anaissie. Slide 56 Discussion Question As we re thinking about, are we getting enough drug to the site of action, should we consider therapeutic drug monitoring? So there are agents that are being used in this individual patient: Isavuconazole, voriconazole, or fluconazole, posaconazole, caspofungin. Slide 57 Answer And if we look at these or the ones that have actual drug-monitoring available, or the ability to send off levels, we re really just looking at voriconazole and posaconazole. And we ll walk through this now in the following slides. Slide 58 Pharmacology of Antifungal Triazoles When we look at our pharmacology of the antifungal triazoles with all of these products, actually, we have both an oral and an IV formulation available. It s noted that itraconazole has always been problematic from an absorption standpoint. So your liquid, as Dr. Anaissie mentioned earlier, is much better than the capsules, but it s always been challenging to get adequate drugs to achieve therapeutic levels.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 14 For posaconazole, the original studies were all performed on the suspension formulations. With the tablet formulation now, we get much more consistent levels than when we used to with the others. Interestingly enough, isavuconazole, well absorbed, currently does not have the ability to do drug monitoring; whereas the posaconazole, the voriconazole, and the itraconazole do, the fluconazole also does not, but it s very well absorbed, in the area of 90%. Slide 59 Voriconazole and Therapeutic Drug Monitoring (TDM) Voriconazole is really a challenge in many ways. It is a non-linear pharmacokinetics, what we call Michaelis Menten kinetics, where we have very rapid rises in levels over a short range of blood levels. There are 2C19 polymorphisms that can lead to either minimal metabolism or really rapid metabolism, which can be challenging to ascertain. Serum levels of less than 1 have been associated with therapeutic failure, while levels above 6 are associated with toxicity, both hepatic and then some of the CNS side effects that we see. Big risk for drug-drug interactions, various levels. Depending on your chemotherapy agent or your immunosuppressant agent, you can increase the levels of those drugs, sometimes multifold. If they re on a enzyme inducer and we would want to check that with our patient, make sure they weren t on something that was going to decrease voriconazole blood levels, which could be an issue. The other interaction which comes up clinically is there are problems with QTc prolongation. Slide 60 Posaconazole and Therapeutic Drug Monitoring (TDM) Posaconazole is also available as a therapeutic drug monitoring. The suspension adds really variable absorption, and it is dependent upon food and the fat content of food, specifically, and then as well as an acid GI status. So the use of proton pump inhibitors or H2 receptor antagonists is relatively challenging, especially the proton pump inhibitors, because they reduce GI acidity so much that you may not be able to get a therapeutic level. With a patient with GVHD, the ability to get a high-fat food in to improve absorption is also challenging with the suspension, so the development of the tablets is a great step forward in the use of this agent. And there is an IV form available, as we mentioned earlier. Serum levels of greater than or equal to.07 are associated with therapeutic benefit, and, generally, greater than or equal to one for treatment, so prophylaxis is little lower than the treatment as far as our target levels. The drug-drug interactions it is important to note this is a strong inhibitor; it s a 3A4, and it also has a QTc prolongation. There is a recent publication that has looked at levels with the tablets vs suspension, and there s a question now as to whether we actually need to do drug monitoring in the prophylactic setting. We would probably still do it for treatment to make sure that we ve achieved an adequate level, when we re treating an individual with a non-fungal infection; however, in the prophylactic setting, it may not be important just cause the tablets are so consistent with their absorption that failures are quite rare. Slide 61 Pharmacist Role in Antifungal Management The pharmacist s role in antifungal management is multifaceted. And we look at drug selection. We look at which drugs will be on the formulary. And then these are expensive agents, often over $1,000 per month of therapy, and the patient is going to need economic support, in many cases, to be able to manage the prescriptions.
Antifungal Strategies for Patients with Hematologic Malignancies or Undergoing Stem Cell Transplant Page 15 With the drug interactions, which I have pointed out in the last two slides, there is significant drug-drug interactions with almost all of these agents. And the drug-food interactions are more important for posaconazole and itraconazole. It s also important that these patients are able to adhere to their daily regimen because, in order to maintain therapeutic blood levels, they re going to have to give him that dose every day. The selection of dosage forms is going to depend on what routes the patient has available. Can they take oral medications, especially when they re having a lot of GVHD symptoms? Are they someone who has trouble swallowing tablets or capsules? And, if they do, do they have IV available to them? And it depends on the treatment setting. We ll look at: the patient s organ dysfunction, whether their liver or kidneys are functioning normally; once again, their route to the administration that are available; careful consideration of concomitant medications, to look at drug interactions; and then are there other disease states that we ll have to take into consideration, whether this be liver dysfunction so a cirrhotic patient, for example, whether it d be someone who has had a prior surgery to their bowel and may have questionable absorption, or other things that may come up. Therapeutic drug monitoring is of benefit if we re at all unsure that we re achieving a therapeutic level. And then the side effect management of these agents is also important. Slide 62 Drug Selection: Reasons for Antifungal Interchange If we look at reasons for interchange and, one, voriconazole and posaconazole are both potent inhibitors of CYP enzymes, so whether we re giving other chemotherapy agents or therapeutic drugs, we re going to have to look at how those agents are metabolized and whether or not they re going to be problematic as far as drug interactions. Do we have to reduce doses? Enzyme inducers may make it impossible to achieve a therapeutic level of an antifungal. And, once again, we may have to alter those agents, depending on what the patient s condition or use of those agents is. If we re going to use suspension, if the patient s unable to take tablets or they re in the ICU setting, and they have a feeding tube in, we are going to have to optimize the feeding formula sometimes to enhance the posaconazole suspension absorption as well as minimizing the use of acid-suppressing agents. During the acute phases of GVHD of the GI tract, posaconazole there is some concern about oral tablet, especially when this patient was having seven watery bowel movements a day. The transit time may be so rapid that we really don t see adequate absorption, and we ll often use an IV formulation. And this actually is maybe where economics come into it. The voriconazole all forms now are generically available so you may see an institution through formulary management that chooses to go with vori IV over the posaconazole IV. If we re uncertain about the oral voriconazole absorption, definitely, we go to intravenous use. So on fluconazole with galactomannan monitoring, as we go to these high-dose steroids, we re generally going to move to a voriconazole or a posaconazole. Liver dysfunction with azoles is problematic. And with patients who have clear dysfunction which may actually be related to the therapy as opposed to the GVHD, we are going to have to think about changing. And you could go rather to amphotericin, your liposomal formulation, or an echinocandin. Voriconazole probably has the highest side effect profile with all of these agents, in that visual side effects along with hallucinations, long-term use, there is a problem with fluorosis, so there s