**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.**
Xin Jiang, Protego Biopharma, San Diego, California

**Main Body of the Abstract**
Light chain amyloidosis (AL) is a rare, progressive, and often fatal protein misfolding disease. In AL, clonal plasma cells overproduce amyloidogenic free light chains (FLCs) that are kinetically unstable, leading to formation of misfolded soluble conformations, fragments, and amyloid fibrils that are toxic to organs such as the heart and kidney. Amongst all AL patients, involved lambda FLC accounts for around 80% of the cases.
Accurate diagnosis of AL has been hampered by factors such as heterogeneity of clinical symptoms and diversity of the FLC sequences. Delayed AL diagnosis is a main contributing factor to the high early mortality seen in the clinic. We developed the AmyLiteTM assay by leveraging the key distinction in varied thermodynamic and kinetic stabilities between amyloidogenic and non-amyloidogenic FLC proteins. The AmyLiteTM assay combines limited proteolysis and the specific detection of the resulting product, namely the dimeric LC constant domain (dLCCD), using a highly sensitive immunoassay. After applying limited proteolysis to plasma samples, the AmyLiteTM assay can specifically (p<0.0001) and sensitively (LLOQ ~4ng/L) detect dLCCD in treatment naïve monoclonal lambda AL patients (N=67), differentiating them from normal controls and patients with multiple myeloma or transthyretin amyloidosis (ATTR). In addition, baseline dLCCD levels from 50 treatment naïve lambda AL patients with known clinical outcome correlate strongly with overall survival (log-rank p=0.0018).
With additional testing and validation, the AmyLiteTM assay could provide a simple and accurate method for early diagnosis of lambda AL, including screening of monoclonal gammopathy patients and monitoring AL patient treatment response or relapse.



AmyLite Assay Quantifies Kinetically Unstable Circulating Amyloidogenic Lambda FLC – Diagnostic and Prognostic Implications for Lambda AL Amyloidosis OA2 (#99)

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.