Clinicians may be right to exercise caution with experimental Ebola treatments

Given the many unanswered questions related to ZMapp, an experimental Ebola treatment, clinicians may be right in exercising caution about using the drug, according to an editorial published on Thursday in Clinicians' Biosecurity News.

Eric Toner, a senior associate at the UPMC Center for Health Security, made the remarks in an editorial on Thursday. ZMapp, a cocktail of three monoclonal antibodies that target three glycoproteins on the Ebola virus, has been used to treat multiple healthcare workers. Toner addressed the question of whether the drug should be made widely available to infected people in Africa.

"The answer depends on a number of clinical issues, such as whether the drug is safe and effective; ethical issues, such as whether adequate informed consent can be obtained and how patients should be prioritized; regulatory issues, if used in the U.S. or elsewhere; and logistical issues, such as how much is available, how quickly could manufacturing be ramped up, and whether the drug can be practically delivered to patients in Africa," Toner said.

ZMapp has demonstrated promise in nonhuman primate studies for treatment of illness and post-exposure prophylaxis but it has not entered human trials. The three Ebola patients who were recently treated, two of whom survived, were the first three humans to receive the drugs. Toner said it was unclear whether the drug had an impact on their clinical course because the patients received other treatments.

"Desperate times may indeed call for desperate action, and in this extreme circumstance it is not unreasonable to consider the use of an untested countermeasure," Toner said. "But to the extent that the many issues outlined above can be minimized, the less difficult the decision becomes. Given the very limited information available and many unanswered questions, clinicians and authorities are right to be very cautious about using these drugs at this time."