An ongoing trial of diflunisal has been closed for enrollment, thus, patients suitable for the study can no longer participate or receive treatment by diflunisal; and patients, who have participated in the trial can not continue their treatment. The investigators want to continue to monitor the effect of the drug on transthyretin (TTR) amyloidosis in an open label observational study.

Primary endpoint will be a composite score of the manifestations of the disease (Kumamoto scale) and secondary end points will be measurements of neurological impairment, heart involvement and nutritional status.

Duration of treatment in this study is dependent of the results from the ongoing IND 68092-study, which are planned to be presented 2013.

Inclusion Criteria:

• Biopsy and genetically proven systemic transthyretin amyloidosis caused by a TTR gene mutation. The amyloid shall be proven to be of transthyretin type, and the fibril composition settled.
• Age ≥ 18 years.
• Negative pregnancy test and contraception for sexually active women of child bearing potential.

Exclusion Criteria:

• Concomitant use of non-study non-steroidal anti-inflammatory drugs (NSAIDs)
• Heart failure with symptoms at daily activities (NYHA class ≥III)
• Renal insufficiency (creatinine clearance < 30 ml calculated from the Cockcroft-Gault formula)
• Active non-haemorrhoidal bleeding within the last 18 month.
• Non-treated peptic ulcer disease.
• Anticoagulation therapy, low dose ASA permitted.
• Non-steroidal or aspirin allergy/hypersensitivity
• Thrombocytopenia (< 100,000 platelets/mm3)
• Inability or unwillingness of subject to give written informed consent
• By the investigator regarded as unable to follow the study guidelines and scheduled controls.

Patients visiting the Units for Familal amyloidosis in Umeå, Piteå and Skellefteå