What are the side effects of Tafamidis (Transthyretin stabilizer)?

From the Guidelines

Tafamidis is generally well-tolerated, with common side effects including urinary tract infections, diarrhea, nausea, abdominal pain, and upper respiratory tract infections, as reported in the 2022 AHA/ACC/HFSA guideline for the management of heart failure 1. The side effects of tafamidis are typically mild to moderate in severity, and the medication is considered to have a favorable safety profile compared to other treatments for transthyretin amyloidosis. Some patients may experience:

• Peripheral edema (swelling in the extremities)
• Headache
• Fatigue
• Skin rashes Less commonly, tafamidis can cause liver function abnormalities, which is why regular monitoring of liver enzymes is recommended during treatment, as noted in the same guideline 1. Serious allergic reactions are rare but possible. It's essential to weigh the benefits of tafamidis against the potential risks, as the medication has been shown to improve cardiovascular outcomes in patients with transthyretin amyloidosis, as demonstrated in the ATTR-ACT clinical trial 1. If you experience persistent or severe side effects while taking tafamidis, it's crucial to contact your healthcare provider rather than discontinuing the medication on your own, to ensure the best possible outcome. The dosage of tafamidis is typically 80 mg once daily, available in 20-mg capsules, or 61 mg once daily, available in 61-mg capsules, as approved by the FDA and reported in the guideline 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Tifamidis Side Effects

• The most common side effects of Tifamidis include:
  • Diarrhoea (26.3%) 2
  • Urinary tract infection (UTI; 25.5%) 2
  • Influenza (21.2%) 2
• Other side effects reported in studies include:
  • Hypoacusis (hearing loss) 3, 4
  • Deafness 3
  • Essential hypertension 3
  • Orthostatic hypotension (low blood pressure when standing up) 5
  • Febrile urinary tract infections 5
  • Severe diarrhoea with faecal incontinence 5
• Tifamidis has also been associated with:
  • Renal and urinary disorders 4
  • Ear and labyrinth disorders 4
  • Blood culture positive and acquired hemophilia (although these are uncommon) 4
  • Death, off-label use, fall, and dysphagia (although these have relatively high occurrence rates) 4

Serious Adverse Events

• Treatment-emergent serious adverse events (TESAEs) were reported in 33.6% of patients in one study 2
• The most common TESAEs were not specified, but the study found that Tifamidis was generally safe and well tolerated in patients with transthyretin amyloid polyneuropathy (ATTR-PN) 2

Patient-Reported Outcomes

• Tifamidis has been shown to improve patient-reported outcomes, including:
  • Kansas City Cardiomyopathy Questionnaire Overall Summary (KCCQ-OS) domain scores 6
  • EQ-5D-3L scores 6
  • Patient global assessment 6
• A greater proportion of patients reported improved KCCQ-OS scores and patient global assessment with Tifamidis compared to placebo 6