Combination Therapy for Lassa Fever
Amesh A. Adalja, MD, FACP, FACEP, FIDSA, June 30, 2017
Lassa fever, a member of the viral hemorrhagic fever class of viruses, is endemic in parts of Africa and causes a considerable burden of disease. The standard treatment involves the use of intravenous ribavirin. The advent of novel antivirals, however, has provided an opportunity to test novel agents and combinations of agents against the virus. A report by the Emory Serious Communicable Diseases Unit, CDC, and others, recently published in Clinical Infectious Diseases, details the experience of combination therapy in patients infected with the virus.
2 Secondary Infections
In this report, the events are described surrounding the secondary infection of 2 individuals from an index patient infected in Togo who was later evacuated to Germany, where he died. The secondary infections occurred in 1 person providing nursing care to the index patient in Togo and another who was a mortician who worked with the index patient’s corpse in Germany. The patients were treated in Emory’s Serious Communicable Diseases Unit and Frankfurt University’s High-Level Isolation unit.
Both patients received combination therapy with intravenous ribavirin and oral favipiravir--a broad-spectrum RNA virus antiviral used for influenza in Japan and experimentally against Ebola. Both patients experienced a decline in viral load; however, without controls, it is difficult to say what effect the antiviral combination had. Favipiravir was stopped in both patients secondary to nausea and increasing liver transaminase levels. Transaminase levels declined after cessation of favipiravir therapy. Interestingly, both patients exhibited persistent viral presence in semen, a sanctuary site where immune surveillance is diminished.
Novel Combinations Merit Further Study
This short report provides evidence that an opportunity exists to augment care for those infected with highly pathogenic viruses acquired in resource-limited settings. Though it is unclear what benefit--and what risk--was conferred by the administration of favipiravir, this experience illustrates that such studies are possible and needed. Future studies with controls will help delineate what benefit is conferred by favipiravir and allow a risk-benefit calculation to be performed given the side effects reported.
The Ebola outbreak demonstrated that effective therapies for high-consequence infectious diseases were desperately needed, and a report such as this is an important step toward optimizing antiviral therapy for this class of infections.
Raabe VN, Kann G, Ribner BS, et al. Favipiravir and ribavirin treatment of epidemiologically linked cases of Lassa fever. Clin Infect Dis June 22, 2017. https://academic.oup.com/cid/article/doi/10.1093/cid/cix406/3883726/Favipiravir-and-Ribavirin-Treatment-of. Accessed June 27, 2017.