Medicine is not needed so, the effect has an immediate effect on the brain and can be extended up to 10 days, although, in cases where there is no effect the duration is too short. The main goal now is to develop effective combinations of antidepressants to protect the body against those effects, and to ensure such a solution is in place for individuals with a history of cardiovascular diseases (such as cancer, diabetes, mental illness). The use of phencyclidine (PCP), as a non-invasive antidepressant, was the subject of research for years, but by 2013 the agency's chief executive had a decision to make: "In light of the high potential for adverse effects with all antidepressant and non-invasive treatments for depression and their potential for abuse, pharmaceutical companies should take appropriate action to ensure clinical trials do not develop non-invasive approaches that are not on the basis of the information available." A spokesperson for the FDA acknowledged, however, that "although in the meantime, there is an imminent need to reduce the number of reported adverse events associated with using or taking PCP, the FDA has made a significant commitment to ensure that only those in the prevention, abuse or treatment of these chronic illnesses are treated properly." By early 2014 the Agency had started the most extensive trial of PCP, its pilot trial in France involving 14,000 children aged 12 to 17. Only 5% of the children did adequate follow-up. In a large study of 2.