**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Marco Basset; Amyloidosis Research and Treatment Center, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo and Department of Molecular Medicine, University of Pavia, Pavia, Italy

**Main Body of the Abstract**
In AA amyloidosis attaining low levels of serum amyloid A (SAA) is associated with prolonged survival. Here we propose new renal response and progression criteria for AA amyloidosis. The study was conducted in the Pavia prospectively maintained database of newly diagnosed patients with AA amyloidosis. Cut-offs of variations in 24h-proteinuria and estimated glomerular filtration rate (eGFR) (at 12 months) from baseline best predicting end-stage renal failure (RF) at 24 months were identified by ROC analysis. Impact of SAA normalization (i.e. <6.4 mg/L; at 12 months) on RF was also evaluated. Of 233 patients 147 (63%) had a second evaluation. Kidney involvement was present in 140 (95%) cases. Nineteen (13%) patients were already on dialysis at diagnosis and were excluded. After a median follow-up of 7.2 years, 36 (24%) patients died and 53 (41%) progressed to RF. A reduction of 24h-proteinuria >40% from baseline, without a worsening of eGFR >20% best predicted progression to RF (at 5 years: 5% vs. 26%, P=0.035; Figure 1A) and was selected as candidate renal response criterion. A reduction of eGFR >20% from baseline predicted shorter time to RF (at 5 years: 13% vs. 31%, P=0.002; Figure 1B). Finally, SAA normalization resulted in prolonged time to RF (at 5 years 7% vs. 36%, P<0.001; Figure 1C). We identified candidates renal response and progression criteria which are ongoing validation in the Heidelberg cohort.



**Author Listing - Lead/ Submitting Author (we will be communicating with this individual): Name, Institution, City and State where the work was done. Co-authors will be added in a separate section.**
Marco Basset; _Amyloidosis Research and Treatment Center, Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Policlinico San Matteo and Department of Molecular Medicine, University of Pavia, Pavia, Italy_

**Main Body of the Abstract**
In AA amyloidosis attaining low levels of serum amyloid A (SAA) is associated with prolonged survival. Here we propose new renal response and progression criteria for AA amyloidosis. The study was conducted in the Pavia prospectively maintained database of newly diagnosed patients with AA amyloidosis. Cut-offs of variations in 24h-proteinuria and estimated glomerular filtration rate (eGFR) (at 12 months) from baseline best predicting end-stage renal failure (RF) at 24 months were identified by ROC analysis. Impact of SAA normalization (i.e. <6.4 mg/L; at 12 months) on RF was also evaluated. Of 233 patients 147 (63%) had a second evaluation. Kidney involvement was present in 140 (95%) cases. Nineteen (13%) patients were already on dialysis at diagnosis and were excluded. After a median follow-up of 7.2 years, 36 (24%) patients died and 53 (41%) progressed to RF. A reduction of 24h-proteinuria >40% from baseline, without a worsening of eGFR >20% best predicted progression to RF (at 5 years: 5% vs. 26%, P=0.035; Figure 1A) and was selected as candidate renal response criterion. A reduction of eGFR >20% from baseline predicted shorter time to RF (at 5 years: 13% vs. 31%, P=0.002; Figure 1B). Finally, SAA normalization resulted in prolonged time to RF (at 5 years 7% vs. 36%, P<0.001; Figure 1C). We identified candidates renal response and progression criteria which are ongoing validation in the Heidelberg cohort.



Biomarker-based renal response and progression criteria in AA amyloidosis: results from the testing cohort of the Pavia-Heidelberg study OC14 (#495)

We invite you to attend the XIX International Symposium on Amyloidosis to be held in Rochester, MN.

This symposium is organized as a hybrid meeting (with the focus on in-person) held from Sunday, May 26 through Thursday, May 30, 2024.

Together with the ISA Board and members of Mayo Clinic, a very attractive scientific hybrid program is being planned. The program will cover a variety of types of systemic amyloidosis: ATTR (hereditary and wild-type), AL (light-chain), AA and less frequent forms. There will be key lectures, specific symposia including those company sponsored, oral presentations and poster sessions of accepted abstracts.

COURSE DESCRIPTION
This program will provide a comprehensive review of state-of-the-art education in systemic amyloidosis: basic science, pathophysiology, diagnosis, current and emerging treatments. Scientific presentations will include competitive oral and poster abstracts. The rapid evolution of scientific discovery and expanding treatment options has created tremendous interest in the field and this meeting will fill and important gap in educating scientists and clinicians.