To answer the questions about the situation in England there is a body called NICE (National Institute for Health and Care Excellence) which decides whether a particular therapy will be paid for by the NHS. The hurdle is currently about £30000 per QALY (quality-adjusted life year). There is also local budget holding that may result in something passed by NICE not being available in a particular location (this is called a post code lottery). Although one may argue with particular decisions, the general principle seems right: without it pharmaceutical companies could charge what they like. Medicines are not free (except to the under 18s, over 60s and special groups, but not PwP), but an annual payment of about £130 will cover all drugs. In practice this means that I get all reasonable Parkinson's drugs, but may be the generic version of some, but not Duodopa.

I share the previous posters' view that we are a long way from personalized medicine. However, as I see it there is a huge benefit from taking the lead ourselves:

Advances in technology, such as cheap computers, smart phones, genetic testing, sensors, etc., have given us the ability to generate huge amounts of data, and the internet gives us the ability to communicate it.

23andMe, who do free genetic testing for PwP.

Even as a trial of size one, ourselves, we can seek to understand the effects of our drugs, monitor their performance and actively look for an optimal dosage regime for ourselves.

John