A life-changing treatment for amyloidosis, a progressive, fatal disease that is disproportionately common in Ireland, is being made available through the Health Service Executive for the first time.
Up to 1 per cent of the population of Co Donegal has been estimated to have the hereditary condition.
Sinn Féin’s Martin McGuinness, whose mother hailed from the Inishowen peninsula, died of the disease in 2017.
The HSE said it has approved reimbursement of the “gene silencing” medicine Patirisan from October 1st, in line with an access protocol to be published shortly.
Patrisan is used to treat hereditary transthyretin-mediated (hATTR) amyloidosis, an inherited, rare, life-limiting and multisystemic disease for which treatment options have been limited up to now.
The condition is caused by deposits of abnormal protein – amyloid – in tissues and organs throughout the body. This can cause tissues and organs to stop working properly.
There are about 30 different proteins that can misfold and form amyloid, and therefore many different types of amyloidosis.
Most occur as rare complications of blood or inflammatory conditions, but up to 10 per cent of cases are inherited.
Patirisan has been available in Northern Ireland since 2019.
"We are thrilled that this day has finally come. Funding for this treatment by the HSE is a milestone many of us have been waiting desperately for," Rosaline Callaghan of the ATTR Amyloidosis Ireland Support Group told The Irish Times.
Ms Callaghan said her father was ill with the disease for seven years and spent 22 months in a hospice before his death.
Her condition was diagnosed in 2007 but progression of the disease has been halted since she started receiving the drug in Derry in 2020.
An average of nine patients a year will be treated with the medicine initially, rising to 45 after five years, the National Centre for Pharmacoeconomics has reckoned. It estimated the cost at €414,000 per patient per year; this was before the HSE concluded price talks with the manufacturer.
Genetic susceptibility
One variant of ATTR amyloidosis was first identified in an Irish family in 1986.
Affected patients have a 50 per cent chance of passing the genetic susceptibility on to their children.
Until recently, many people with ATTR amyloidosis were misdiagnosed as having heart disease due to other, more common, symptoms such as high blood pressure.
A 1995 study of the Donegal cases found that nearly all those affected were descended from "a man called Conall Gulban, after whom the county Donegal [previously known in Gaelic as Tír Chonall, meaning land of Conall] is named".
The deposition of proteins that occurs with amyloidosis can cause tissues or organs to stop working properly. The deposits are formed when normally soluble body proteins clump together and remain in the tissues rather than being safely cleared away.
Amyloid deposits can lead to stiffening of the heart muscle, leading to symptoms such as shortness of breath, abnormal rhythms, weight loss, fatigue and dizziness. Where deposits occur in the nerves, this can lead to symptoms such as fainting and stomach problems.