Brief Answer:
No cure is really effective.

Detailed Answer:
I read your question carefully and I understand your concern about your nephew.

It is called motor neuron disease because it affects primarily nervous system cells in the brain and spinal cord which control the activity of the muscles. It is a neurodegenerative disease, meaning that nerve cells die progressively. As a result there is progressive weakness of the limbs, difficulty swallowing and speaking making the patient gradually disable and generally succumbs to respiratory complications.

I know that you have come here hoping for a treatment. Unfortunately though until now modern medicine has been unable to find a cure for this disease. Medications effective in slowing it down are lacking as well. There is a medication called riluzole which slows down progression some what, but it has only a modest effect, the disease does eventually progress.
The rest of the treatment consists only in trying to alleviate the present symptoms, not alter the course of the disease.

One thing though, you should really make sure it is the right diagnosis, perhaps even ask a second opinion. By that I do not mean to say there is anything bad with your current doctors, I am saying it only because 26 is not a typical age for this disease, I have never had a patient under 30, the mean age is about 55 years old. So being such a serious diagnosis it has to be made sure.

I remain at your disposal for further questions.

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