Mens rea is a completely separate concept - it's merely intent to do the action, not a motive. That is, the criminal deliberately punched the victim, rather than accidentally hitting them in the face while trying to put out a fire - there is no requirement that we know why the crime was committed, only (usually) that it was deliberate. Do you really want to argue legal technicalities with a lawyer, even a very sick one? I think "how" has already been somewhat established in the case of Rituximab - by depleting B-cells. And again, that is far more than drug companies are required to show. The FDA and other drug approval bodies have little interest in "why" OR "how", so long as the "what" is satisfactory. More broadly I would argue that the safety of Rituximab use in ME/CFS is derived from the safety of its use in human beings. Cancer patients do not have major differences in general physiological functions compared to ME patients, hence there is no reason to assume that ME patients will spontaneously combust when taking the same drugs that do not cause cancer patients to spontaneously combust. Preliminary studies on effectiveness indicate improvements are far more impressive than "mild" and in significant majority of patients. Benefit is thus far looking relatively high at least in the short term, while risk, as established in extensive studies with other diseases, is relatively minimal. And our levels of impairment aren't profound? I doubt there's a lot of ME/CFS patients at 80% functionality eager to try Rituximab at this point. From what I have read, and based on the studies thus far, the ME patients seeking treatment are severely impaired - unable to work and struggling to get out of the house or do basic household tasks. Known risks have been established in cancer studies, and the small trials done thus far haven't indicated additional risks. When a drug is prescribed, the FDA has a nice leaflet with it listing the side effects and their frequencies. So that gets to conveyed to the patient just like it does for every other drug. In the case of Rituximab, there's an increased chance of infection - something like 15% higher than the odds for controls. I think it's improper of you to presume doctor misconduct in absence of any evidence, especially while naming a specific doctor. There is no indication that Dr Kogelnik or others are not keeping close tabs on their patients. I take a medication prescribed (so far) from a considerable distance, and my GP does not feel qualified to handle it, but it is very easy for me to email or Skype the prescribing doctor to discuss things. If side-effects do arise requiring emergency treatment, it is highly likely that the local hospital would be able to provide appropriate treatment for those side-effects.