Doctors may suspect ATTR amyloidosis on the basis of patients’ symptoms, findings on physical examination and sometimes family history. The diagnosis can be confirmed (or eliminated) by tests including:
- Tissue biopsy
- Genetic testing
- Imaging studies
Treatment of all types of amyloidosis is currently based on the following principles:
- Reducing the supply of amyloid forming precursor proteins.
- Supporting the function of organs containing amyloid.
When amyloid precursor protein supply is controlled:
- existing amyloid deposits often regress (become smaller)
- new amyloid deposits stop appearing
- organ function is often preserved and may also recover
Treatment plans include:
Supportive treatment – treating your symptoms. Due to the progressive nature of hATTR amyloidosis, managing symptoms is an ongoing process. Doctors can prescribe medications to help with the symptoms to lessen the pain and the symptom itself. Examples that a physician may recommend include:
- Diuretic medicine to remove extra water from the body
- Thickeners to add to fluids to prevent choking if a person has trouble swallowing
- Compression stockings to relieve swelling in the legs or feet
- Dietary changes, especially for people who have gastrointestinal amyloidosis
Source treatment – slowing down, or stopping, the overproduction of amyloid at the source of the disease.
- Until now, a liver transplant has been the only option for treatment of hATTR amyloidosis. TTR is mostly made by the liver and a transplant will reduce the production of the abnormal TTR protein. The outcome of liver transplantation is largely dependent on the mutation that exists in the patient.
- More recently, several drugs have been developed for the treatment of the underlying cause of hATTR, some of which are still investigational and some of which have been approved in countries such the UK, Canada and Europe. Inotersen (Tegsedi™) was approved following a priority review by Health Canada in October 2018 for the treatment of stage 1 or stage 2 polyneuropathy in adult patients with hATTR amyloidosis. Inotersen was also approved in Europe in July 2018 and in the US in October 2018. Inotersen works by ‘silencing’ gene expression and targeting transthyretin (TTR).
Other drugs take different therapeutic approaches to treating hATTR and are aimed at:
Stabilizing the TTR protein – The approach of TTR stabilizers is to stop the TTR protein from forming amyloid deposits.
- Diflunisal – Approved as a non-steroidal, anti-inflammatory drug (NSAID) that has shown to bind to the TTR protein in the blood and may thereby prevent the formation of amyloid. Studies are currently underway to assess the effect of diflunisal on the progression of neuropathy and cardiomyopathy in patients with hATTR amyloidosis.
- Tafamidis (Vyndaqel®) – Completed clinical trials for hATTR neuropathy and cardiomyopathy; currently approved in Europe, US, Japan, Russia, and Argentina for the treatment of transthyretin familial amyloid polyneuropathy (TTR-FAP) in adult patients with stage 1 symptomatic polyneuropathy.
Stopping the production of TTR proteins – The approach of stopping the production of TTR proteins is to prevent TTR protein production by blocking or ‘silencing’ the TTR gene.
- Inotersen (Tegsedi™) – Approved following priority review by Health Canada in October 2018 for the treatment of stage 1 or stage 2 polyneuropathy in adult patients with hATTR amyloidosis. Inotersen was also approved in Europe in July 2018 and in the US in October 2018.
- Patisiran (Onpattro™) – Approved in the US and Europe in August 2018 and UK in July 2019 for the treatment of hATTR amyloidosis in adults with stage 1 or stage 2 polyneuropathy.
*information taken from