Research Studies

Dr. Karen Zimowski is a pediatric hematology/oncology fellow at Emory University/Children's Healthcare of Atlanta (CHOA). Dr. Zimowski received her BS in Biochemistry from Clemson University and her MD from the Medical College of Georgia. She completed pediatric residency at Johns Hopkins University. As a NHF-Shire Clinical Fellow, she will receive clinical training under the guidance of Drs. Robert Sidonio and Shannon Meeks in the Comprehensive Bleeding Disorders Clinic at CHOA and Special Coagulation Laboratory at Emory University. In addition, she will continue her current research projects, investigating the structure-function relationships of both coagulation factor V and factor VIII. Dr. Zimowski aims to become an expert physician-scientist in the field of pediatric hemostasis and thrombosis. She seeks to apply the knowledge gained through laboratory analysis to the clinical setting and provide the highest level of medical care to patients with bleeding and coagulation disorders.

Dr. Patricia Zerra is currently completing her pediatric hematology/oncology fellowship at Emory University/Children's Healthcare of Atlanta (CHOA) and will begin an additional fellowship in Transfusion Medicine focusing on coagulation in July 2017. Dr. Zerra graduated from Connecticut College followed by two years of research at Boston Children's Hospital. She received her M.D. from Jefferson Medical College in Philadelphia and completed pediatrics residency at the University of Miami/Jackson Memorial Hospital where she served as chief resident with an additional year practicing general pediatrics. As an NHF-Shire Clinical Fellow, Dr. Zerra will work under the mentorship of Dr. Robert Sidonio, Pediatric Director of the Emory/CHOA Hemophilia Treatment Center to focus on the clinical management of children with bleeding disorders. She will also continue her current research under the mentorship of Drs. Shannon Meeks and Sean Stowell, focusing on the immune response to FVIII in an effort to identify initiating immune events that can serve as targets to prevent FVIII inhibitor formation. Her goal is to serve as a pediatric hematologist and clinical/translational researcher focusing on the care of pediatric patients at risk for developing inhibitors.

Background:

Emicizumab was approved by the FDA in 2017 for routine prophylaxis in PwHA with inhibitors. HAVEN 1, a phase III study in adolescent and adult PwHA with inhibitors, demonstrated that emicizumab prophylaxis significantly reduced annualized treated bleed rate by 87% (P<0.001) vs no prophylaxis. In this retrospective, post-hoc analysis, we examined the use of BPAs to treat breakthrough bleeds before and after emicizumab initiation in HAVEN 1.

Methods:

HAVEN 1 patients were included from emicizumab-treated Arms A (previously treated with only episodic BPA) and C (previously treated with prophylactic BPA) and who had participated in the non-interventional study (NIS). In both studies, bleed and treatment data collection were comparable. In the study protocol, no guidance for the treatment of bleeds was provided; and hemostatic efficacy was not measured, thus optimal treatment of bleeds cannot be accurately assessed. Additionally, only data before October 7th, 2016 are included in this analysis to better represent treatment patterns before amended BPA guidance was provided. We describe the total number of patients and bleeds, number of infusions per bleed, and the cumulative dose/kg per bleed before and after emicizumab initiation.

Results:

This analysis (48 total patients) included 24 patients each from Arm A and Arm C who participated in the NIS prior to enrollment in the HAVEN 1 trial. On average, patients received numerically fewer activated prothrombin complex concentration (aPCC) infusions with lower cumulative doses while on emicizumab as compared to prior to emicizumab administration. In Arm A, 11 bleeds were treated with aPCC resulting in an average of 1.2 aPCC infusions/ bleed and an average cumulative aPCC dose/ bleed of 95.9 U/kg while on emicizumab as compared to 136 bleeds resulting in an average of 1.7 infusions/ bleed and cumulative dose 134 U/kg prior to emicizumab. Similar findings were seen in Arm C (bleeds, aPCC infusion/cumulative dose numbers: 14,2.3/166.6 U/kg on emicizumab compared to 205, 2.6/189 U/kg prior to emicizumab.) Fewer bleeds were treated with rFVIIa and no clear trend was seen regarding how rFVIIa was used to treat bleeds. In Arm A, 11 bleeds were treated with rFVIIa resulting in an average of 1.5 infusions/ bleed and cumulative dose 212.2 µg/kg on emicizumab, vs 97 bleeds, 1.4 infusions/ bleed and cumulative dose 181.6 µg/kg prior. In Arm C, 14 bleeds were treated with rFVIIa resulting in 4.4 infusions/ bleed and cumulative dose 555.6 µg/kg on emicizumab vs 58 bleeds, 8.6 infusions/ bleed and cumulative dose 1829 µg/kg prior.

Conclusions:

Treatment of bleeds with aPCC in HAVEN 1 resulted in numerically fewer infusions and lower cumulative doses of aPCC per bleed while on emicizumab when compared to bleeds treated prior to emicizumab initiation. Treatment of bleeds with rFVIIa showed no clear trend.

As a social worker at Gulf States Hemophilia & Thrombophilia Treatment Center, I have the privilege of serving patients across their lifespan. I would like to initiate grass roots education about hemophilia in Houston, Texas, by offering educational programming to specialized health care professionals who work directly with the aging population in nursing homes and assisted living communities. This would include executive directors and administrators of these facilities as well as direct clinical staff.

Dr. Shi is a Professor of Pediatric Hematology at the Medical College of Wisconsin and an Investigator of Blood Research Institute at the BloodCenter of Wisconsin. She earned her MD from Fujian Medical University in China in 1990 and her Ph.D. in 1998. Dr. Shi’s research focus is to formulate innovative therapeutic approaches for the treatment of hemophilia A, a genetic bleeding disorder caused by a lack of the critical blood clotting protein, factor VIII (FVIII). One of her research programs funded by the National Institutes of Health, National Heart, Lung, and Blood Institute, is to develop platelet-specific gene transfer strategies for the treatment of hemophilia A and hemophilia A with neutralizing antibodies. In the project supported by the NHF Bridge Grant, Dr. Shi will investigate the potential effect of the FVIII carrier protein, von Willebrand factor, on FVIII immune responses in hemophilia A. Dr. Shi expects that results from her studies will aid the design of more effective protocols to prevent FVIII immune responses and to induce FVIII immune tolerance in patients with HA.

Per Dr. Kumar, the JGP Fellowship has enabled him to test his ideas related to factor V biology. It has facilitated his scientific training to become increasingly independent in the planning and execution of his research. Important to note, findings generated from these studies have provided new concepts and tools to target factor V for therapeutic purposes. After the completion of his award in 2018, Dr. Kumar would like to continue his career in the field of hematology.