A drug that scientists had hoped would prove effective against the polio-like illness that is causing paralysis in children has flunked its first test. A study published in the journal Neurology found that fluoxetine was ineffective against the disease, acute flaccid myelitis.
There have been at least 127 cases of the disease, also called AFM, this year, according to the Centers for Disease Control and Prevention. That’s a significant increase over 2017 and is a trend for a disease that is little understood and for which there is no specific treatment.
Researchers think that that an enterovirus, EV-D68, is a possible cause of the disease and lab tests had shown that fluoxetine, an antidepressant, might have antiviral effects against it but the study found it ineffective.
“The lack of an efficacy signal for the treatments for acute flaccid myelitis evaluated in this study emphasizes the need for development and prospective evaluation of more effective treatment and prevention strategies for this potentially devastating condition,” said study author Kevin Messacar, MD, of Children’s Hospital Colorado in Aurora, in a news release.
AFM can cause cause sudden muscle weakness in the arms, legs or neck, drooping eyelids and difficulty swallowing, speaking and breathing. While its cause is still unknown, the CDC says that possible causes include the West Nile virus, the polio virus and certain other viruses.
Preventive measures recommended by the CDC include getting the polio vaccine and avoiding mosquito bites, which can spread the West Nile virus. Washing your hands often is also recommended.
About the study
In the fluoxetine study, researchers looked at the cases of 56 children with acute flaccid myelitis in 2015-2016 from 12 medical centers across the country. The children ranged in age from 2-1/2 to 9 years old.
The 28 children who received more than one dose of fluoxetine were compared to the 26 children who did not receive the drug and two who had only one dose and were considered part of the untreated group. The children’s muscle strength in their arms and legs was recorded to determine whether the drug was effective.
At their first exams, there was no difference between the two groups in muscle strength. But by the end of the study an average of seven months later, the children who had taken the drug had lower strength scores than the children who did not receive treatment. After adjusting for factors that could affect the results, such as age, sex, other treatments the children received and their strength level at the first exam, the researchers found that on a scale of 0 to 20 that grades muscle strength throughout all four limbs, the strength scores of children who received the drug worsened by 0.2, while the scores of those who did not receive the drug improved by 2.5.
Messacar noted that the study has several inherent limitations in that it was looking back in time, patients were not chosen at random to receive the treatment or not and doctors and patients and their families were aware that they were receiving the drug. In addition, the small number of patients may make it difficult to draw definite conclusions.