Professor Philip Routledge, of Cardiff University, will review current new medicines assessment processes against those of similar organisations elsewhere, to see if there are any areas that Scotland could learn from.
Campaigners have complained that drugs for diseases such as cancer are available in other parts of the UK and Europe but are not routinely offered to patients in Scotland on the NHS. Patients instead have to apply for drugs not approved for widespread use by the Scottish Medicines Consortium (SMC) on a case-by-case basis by submitting an Individual Patient Treatment Request (IPTR).
The Scottish Government ordered an initial review nearly a year ago, after critics claimed a cross-border divide in availability of new medications had been created. The probe, carried out by Scotland's Chief Medical Officer, Sir Harry Burns, and the Chief Pharmaceutical Officer, Professor Bill Scott, decided to allow a system of IPTR to bed in before a further review.
That review emerged after Joyce Juszczak, 66, was refused the drug eculizumab for a life-threatening blood condition.
Mrs Juszczak, from Gourock, was only given eculizumab when she suffered a potentially fatal blood clot. She went seven months without the treatment after a failed IPTR and subsequent appeals.
The Scottish Government said Mr Scott will assess how the SMC's decisions are implemented by NHS boards to ensure there is a "consistent and effective approach to prescribing policies across the country".
Alastair Kent, director of Genetic Alliance UK, said: "It is a shame it has taken this long to reach a conclusion we have been advancing for some time."