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FEATURE Drawing First Blood We invite two experts to debate controversial topics in hematology and health care. Are New Treatment Options for Beta- Thalassemia Ready for Widespread Use? Alexis Thompson, MD, MPH Thomas Coates, MD Disclaimer: The following positions were assigned to the participants and do not necessarily reflect ASH opinions, the participants’ opinions, or what they do in daily practice. Agree? Disagree? We want to hear from you! Send your thoughts and opinions on this controversial issue to ashclinicalnews@ hematology.org. ASHClinicalNews.org Patients with transfusion-dependent beta-thalassemia, the most severe form of the disease, require lifelong management with red blood cell (RBC) transfusions, presenting a substantial cost and burden to patients. The only curative treatment for patients with transfusion-dependent beta-thalassemia is alloge- neic hematopoietic cell transplantation (alloHCT), which also is associated with a variety of adverse events. Also, many patients lack a suitable donor for the procedure. Finding new treatment options for these patients is a high priority for the hematology community. One of the most promising advances for patients with severe beta-thalassemia in recent years is the use of gene therapy with autologous CD34-positive cells transduced with the beta globin–containing lentiviral vector. Last year, 2018 American Society of Hematology (ASH) president Alexis A. Thompson, MD, MPH, and colleagues published results of two companion phase I/II trials (HGB-204 and HGB-205) in which gene therapy reduced or eliminated the need for long-term RBC transfusions in certain pa- tients with transfusion-dependent beta-thalassemia. 1 Similar results from the phase III Northstar-2 and Northstar-3 studies shared at the 2018 ASH Annual Meeting added to the excitement around using this type of gene therapy in patients with severe beta-thalassemia. 2 Also at the 2018 ASH Annual Meeting, researchers presented findings from the phase III BELIEVE study that evaluated luspatercept, a first-in-class recombinant fusion protein, in patients with transfusion- dependent beta-thalassemia. Treatment with luspatercept alleviated patients’ transfusion burden, with approximately 70% of participants achieving a clinically significant reduction in RBC transfusion require- ments during any consecutive 12 weeks of treatment, the authors reported. 3 As the treatment options for transfusion-dependent beta-thalassemia continue to expand, ASH Clinical News invited Dr. Thompson and Thomas Coates, MD, to discuss the status of these options and answer the question, “In patients with transfusion-dependent thalassemia, should gene therapy be the first approach or the last resort?” Dr. Thompson is professor of pediatrics at Northwestern Medicine and Feinberg School of Medicine in Chicago. Dr. Coates is professor of pediatrics at Keck School of Medicine at the University of Southern California in Los Angeles. Alexis Thompson, MD, MPH: In the very near future, patients with beta-thalassemia may have a variety of treatment options that are either disease-modifying or poten- tially curative, so we need to think about which patients are the best candidates for these therapies and what the intent of therapy is. Today, we have well-established conventional therapies, including trans- fusion and iron chelation (plus compre- hensive care to manage complications), that are sufficient for most patients. We are thrilled to see adult patients with beta-thalassemia living longer lives, but these methods, while life-sustaining, are not curative. Gene therapy represents a promising option for older children and young adults with beta-thalassemia, and we are awaiting more information about its safety in people older than 40 years. Thomas Coates, MD: Gene therapy abso- lutely is an exciting new option. Ulti- mately, it probably will be the direction that treatment will take, but right now, it is just barely ready for prime time. One of the most pressing issues is that, in the U.S., few centers have exper- tise in managing thalassemia. We both know that if patients’ disease is managed well with transfusion and their iron level is controlled perfectly, they can expect to live into their 60s. The caveat is that they have to have a physician who under- stands all the nuances of how to manage the disease. The ability to cure disease – especially in a younger patient – and eliminate decades of transfusions is a great opportu- nity. The good and the bad news for gene therapy, though, is that alloHCT methods are also rapidly improving. So, there are several competing options for patients with severe beta-thalassemia. Dr. Thompson: I agree; not every patient is looking for curative therapy. Some patients feel that their condition is being managed effectively and that they have made whatever lifestyle adjustments they needed to achieve an acceptable qual- ity of life. Given our improved ability to provide safe blood and chelate iron to control side effects, I can’t argue with patients who want to make only minor changes to therapy to maintain a certain quality of life. Others, like people with young chil- dren, have great enthusiasm about gene therapy. Research studies of gene therapy have been conducted in adolescents and young adults with beta-thalassemia, and there are many reasons why this may be the population where we see the greatest long-term benefit. For example, alloHCT with a sibling donor is considered a standard of care for transplant-eligible patients with beta- thalassemia; many patients, however, lack this type of suitable donor. Gene therapy is quite appealing as an alternative, cura- tive treatment. Dr. Coates: Yes, if a patient has a matched ASH Clinical News 43