Akari Therapeutics Announces Initiation of Pivotal Phase III Trial of Nomacopan in Pediatric Hematopoietic Stem Cell Transplant-Related Thrombotic Microangiopathy (HSCT-TMA) Following the Opening of its IND

NEW YORK and LONDON, December 23, 2019 – Akari Therapeutics, Plc (Nasdaq:AKTX), a biopharmaceutical company focused on innovative therapeutics to treat orphan autoimmune and inflammatory diseases where the complement and/or leukotriene systems are implicated, announces that a U.S. Food and Drug Administration (FDA) investigational new drug application (IND) is open for its multicenter Phase III study for the treatment of pediatric HSCT-TMA with nomacopan, allowing clinical sites to open in the first quarter of 2020.

“With the pediatric HSCT-TMA IND now open we look forward to starting the pivotal Phase III study of nomacopan in HSCT-TMA, a potential treatment for a high risk pediatric population that suffer very high death rates and for which there are currently no approved therapies. If successful, we expect HSCT-TMA to be a gateway into a range of other poorly treated orphan TMAs,” commented Clive Richardson, CEO of Akari Therapeutics. “In addition, following the recent successful completion of our Phase II bullous pemphigoid study, we expect data from our Phase I/II atopic keratoconjunctivitis trial in early 2020 and interim data from our Phase III paroxysmal nocturnal hemoglobinuria trial in the first half of 2020.”

HSCT-TMA is an orphan hematological condition that occurs in up to 30% of patients who have received a hematopoietic stem cell transplant (HSCT). There are no approved treatments for pediatric HSCT-TMA, and it has an estimated mortality rate of more than 80% in children with the severe form of the disease¹. It is this severe form that is being targeted with nomacopan which is a bifunctional inhibitor of complement C5 and leukotriene B4 (LTB4). Following the recent end-of-Phase II meeting with the FDA, Akari has now opened an IND to initiate its pivotal pediatric HSCT-TMA study based on a single arm responder-based design. Recruitment will be focused on specialist pediatric sites in the U.S. and Europe where treatment tends to be concentrated in specialist centres.

Whilst the role of complement inhibition is understood to play an important role in pediatric HSCT-TMA, the Company believes LTB4 may also be an important target in reducing epithelial activation in both TMA and graft versus-host disease² (GVHD) which often occur simultaneously. The Company believes daily dosing with nomacopan may also be of particular advantage in facilitating more complete complement suppression, especially in HSCT-TMA patients with high transfusion requirements.

As previously announced, this two-part pivotal Phase III study of nomacopan in pediatric patients with HSCT-TMA is based on guidance from the Company’s end-of-Phase II meeting with the FDA. Part A of the trial is a dose confirmation study. Part B of the trial is a single arm responder-based efficacy study that will follow an interim analysis of Part A and a meeting with the FDA. Akari has both FDA fast track and orphan status for this program.

1 Sonata Jodele, et al. New approaches in the diagnosis, pathophysiology, and treatment of pediatric hematopoietic stem cell transplantation associated thrombotic microangiopathy. Transfus Apher Sci . 2016 April; 54(2): 181–190

2 Takatsuka, et al. Predicting the severity of intestinal graft-versus-host disease from leukotriene B4 levels after bone marrow transplantation. Transplantation 2000, 26: 1313-1316

About Akari Therapeutics

Akari is a biopharmaceutical company focused on developing inhibitors of acute and chronic inflammation, specifically for the treatment of rare and orphan diseases, in particular those where the complement (C5) or leukotriene (LTB4) systems, or both complement and leukotrienes together, play a primary role in disease progression. Akari's lead drug candidate, nomacopan (formerly known as Coversin), is a C5 complement inhibitor that also independently and specifically inhibits leukotriene B4 (LTB4). Nomacopan is currently being clinically evaluated in four indications: bullous pemphigoid (BP), atopic keratoconjunctivitis (AKC), thrombotic microangiopathy (TMA), and paroxysmal nocturnal hemoglobinuria (PNH). Akari believes that the dual action of nomacopan on both C5 and LTB4 may be beneficial in AKC and BP. Akari is also developing other tick derived proteins, including longer acting versions.