The tragic death of Anita Louise, a participant of the experimental multiple sclerosis drug trial in 2002 has been brought back to focus by two neurologists from Stanford University. The authors warn about the dangers associated with drug testing, more so when the adverse effects of the experimental drug is unknown.
The drug natalizumab, marketed under the brand name was granted fast track status by the FDA in 2004. Soon after the approval, the drug use was found to be associated with a potentially fatal infection, progressive multifocal leukoencephalopathy (PML). The observation of infection in a patient who was devoid of the disease prompted the researchers to investigate further.
The researchers argue that healthy volunteers should not be allowed to participate in such drug trials, as they do not derive any benefit out of it. Furthermore, they feel that drugs associated with a risk of death should only be used in patients diagnosed with the disease, after all possible treatments have been found to be ineffective.
Multiple sclerosis is the manifestation of myelin sheath destruction surrounding the nerve cells. The immune system cells attack the myelin sheath, eventually leading to loss of control over motor function and even paralysis. The drug was found to block this effect.
It was highlighted that the inhibition of immune cells, could lead to an increased susceptibility to infections. In fact, PML is an infection that usually affects immunocompromised individuals such as transplant recipients, AIDS victims etc.
The drug was withdrawn from clinical use three months following its approval. With this being the situation, the FDA has taken up the re-approving of the drug as a single therapy. The advisory panel members would get together on the 7th and 8th of March to discuss the issue.
'A big mistake was made in these trials that, in my opinion, is easily preventable. All they need to do is tighten up entry criteria into multiple sclerosis clinical trials and we could avoid similar types of problems in other trials,' concluded Langer-Gould, one f the senior researchers involved in the study.