A SPECIAL £21 million fund for treating patients with rare conditions has been questioned after nearly 86 per cent of the budget was spent on one drug.

New figures, which the Scottish Government tried to withhold, show that £18.6m was used to fund Ivacaftor for people with a rare form of cystic fibrosis.

The revelation has renewed calls for product developer Vertex to reduce the cost of the drug – thought to cost around £180,000 a year per patient.

Former Scottish Government Health Secretary Alex Neil launched the Rare Conditions Medicines Fund (RCMF) in 2013 in an attempt to fund medicines for illnesses affecting fewer than one in 2,000 people.

The fund covered treatments rejected by the Scottish Medicines Consortium, an NHS body that makes decisions on whether patients should have access to new drugs.

This newspaper asked the Government to list the 10 drugs that had taken up most of the budget and how much each of these treatments cost. Ministers knocked back the request but the Scottish Information Commissioner backed the Sunday Herald.

The figures reveal that £18.6m of the £21.7m fund in 2013/14 went on the Ivacaftor tablets.

It is understood the sum covered the purchase of two years’ worth of the drug, which is also known as Kalydeco.

The second highest spend was £660,000 on Eculizumab, which treats haemolytic uraemic syndrome, followed by £455,000 on cancer drug pomalidomide.

In 2013, the SMC knocked back the application by Vertex Pharmaceuticals to have Ivacaftor approved.

The spending on Ivacaftor has been of huge help to people with cystic fibrosis, but the figures have again raised questions about whether drug companies do enough to lower their prices.

In 2012, it was reported that US doctors and researchers involved in the drug’s development had complained to Vertex about the price.

It is unclear how much Ivacaftor charges the NHS in Scotland for its tablets, but it was reported in 2013 that it could be around £180,000 per patient.

The RCMF has since been replaced with the New Medicines Fund and Ivacaftor accounts for a much smaller proportion of this budget.

David Miller, a Sociology professor at Bath University, said: “No wonder they [the Scottish Government] wanted to keep this quiet. It is amazing that one corporation can profiteer from the NHS by hoovering up the vast majority of the special fund. There needs to be much more transparency about these kinds of decisions.”

A spokesperson for Vertex said: “The price of Ivacaftor is based on the benefits the medicine brings by treating the underlying cause of the disease, the very small number of people eligible for the medicine and, importantly, our commitment to and significant investment in continued research to develop new medicines to help even more people with CF.”

The Scottish Government was unable to comment due to purdah. An SNP spokesperson said: "We have taken the steps that we can to improve access to new medicines and it is time for the industry to follow that example."