Covid-19 has spread rapidly throughout the world causing widespread panic, death, and injury. While this virus is the provocateur, it is often the patient's own disproportionate immune response which deals the most devastating (and often fatal) damage. A specific part of the immune system, known as the complement, has been shown to cause such damage in other types of coronaviruses. In the SOLID-C19 study, Soliris (Eculizumab) will be used to modulate the activity of the distal complement preventing the formation of the membrane attack complex. By modulating this portion of the immune response, mortality can be halted while the patient has time to recover from the virus with supportive medical care.