Navigating the Data, Treatments and Breakthroughs of hATTR Amyloidosis
According to the Amyloidosis Foundation, today’s treatment plans are two-fold:
Supportive treatment – treating your symptoms and organ damage
Source treatment – slowing down, or stopping, the overproduction of amyloid at the source of the disease.
Supportive treatment is helpful for various symptoms, including peripheral neuropathy, autonomic neuropathy, and cardiac and kidney problems, and can change the quality of life for many people. There are several medications that can be prescribed to treat peripheral neuropathy, which can cause tingling or burning in some parts of the body. These medications can help with pain relief and nerve damage. If a patient has autonomic neuropathy, symptoms can vary, with common problems affecting blood pressure, heart rate, digestion, and perspiration, depending on the location of the damage to the nerves. Other gastrointestinal dysfunctions may require treatment for symptoms that include poor nutritional health, diarrhea or constipation, and nausea or vomiting. Doctors can prescribe medications to help with these symptoms to lessen the pain and the symptom itself.
Management of heart problems, heart failure, and kidney dialysis (when needed) make a significant improvement on a patient’s quality of life. Reversing any damage to the organs and other parts of the body is difficult to achieve. If treatment begins during the early onset of clinical symptoms, the overall success rate is higher, so early detection is essential.
For most ATTR variations, the liver is the main source of amyloid production. However, the liver itself is not affected by the disease in most cases and the amyloid burden causes damage in other parts of the body. A liver transplant is very helpful in reducing (or stopping) the amyloid deposits. It can stabilize or improve neurological symptoms as well as gastrointestinal problems (which can correct poor nutrition and overall health). However, the statistics vary as to who can benefit from these transplants, with the more common ATTR Val30Met having the highest success rate. The outcome of liver transplantation is largely dependent on the mutation that exists in the patient. In some cases, amyloid deposition does completely stop after transplantation, so research is ongoing in this area. For those patients with cardiac symptoms, studies have shown that heart problems may continue after a liver transplant. In some situations, a combined heart and liver transplant will help a patient with an ATTR variant that produces advanced cardiac problems. In 2018, two drugs were approved by the FDA for ATTR polyneuropathy of hereditary transthyretin-mediated (hATTR) amyloidosis in adults. The first was ONPATTRO (patisiran) lipid complex injection, a first of its kind RNA interference therapeutic. This drug aims to silencing the gene expression.