A Multicenter, Multi-Outbreak, Randomized, Controlled Safety and Efficacy Study of Investigational Therapeutics for the Treatment of Patients With Ebola Virus Disease

Species Zaire ebolaviruses (EBOV) are members of the Filoviridae and are known primarily as the underlying cause of severe viral hemorrhagic fevers with disturbingly high case fatality rates. Between 1994 and the present, there have been many filovirus outbreaks affecting mostly central Africa, with 2 large outbreaks in 1995 in Kikwit, Democratic Republic of Congo (DRC), and in Gulu, Uganda in 2000-2001. The 2013-2016 West African outbreak significantly exceeded all previous outbreaks in geographic range, number of patients affected, and in disruption of typical activities of civil society. In 2018 there have been two additional outbreaks of EBOV infection, both in the Democratic Republic of the Congo and constituting the 9th and 10th recorded outbreaks of this infection in that country. The 10th outbreak is currently ongoing in the DRC as of December 2018 and has raised great concern because of the potential to expand greatly in scope and to spread to surrounding regions.

It has been suggested that one of the most important elements necessary to improve survival from Ebola virus infection is the provision of supportive care inclusive of hemodynamic support in the form of aggressive fluid replacement, ability to diagnose and correct severe metabolic derangements, early treatment of sepsis, and other standards of modern medical care. A small number of investigational therapeutics have been developed as putative antiviral strategies for treating this infection. Unfortunately, phase 1/2 data supporting the safety and efficacy of these agents are often limited, and thus there remains some degree of equipoise as to which of these interventions should be prioritized in the treatment of severe infection. The triple monoclonal antibody product ZMapp was studied through a randomized controlled trial (RCT) in the 2014-2016 West African outbreak and remains perhaps the best characterized of the available investigational products, but the end of that outbreak forced the RCT to close prior to crossing pre-specified evidentiary boundaries.

A WHO Research and Development Ebola Therapeutics Committee has agreed that, given the lethality of Ebola virus and the combination of human and non-human primate (NHP) efficacy data for ZMapp, either ZMapp+oSOC or oSOC alone could potentially be positioned as the control arm in comparative trials depending upon the preferences of the host countries. The DRC has chosen to use ZMapp + oSOC in the current protocol. However, both the nature and number of control and invegstigational arms may change over the course of the trial. Such changes would require protocol amendments.

This multicenter, multi-outbreak, randomized controlled trial will study the comparative safety and efficacy of additional investigational therapeutics compared to ZMapp in patients with known EBOV disease (Zaire) receiving oSOC. The primary endpoint of this comparison will be mortality by Day 28, with a number of secondary endpoints also planned that should generate important knowledge about the safety, ease of administration, and antiviral activity of all of these investigational interventions.