**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.**
Saurabh Zanwar, Mayo Clinic, Rochester, MN

**Main Body of the Abstract**
Background: Daratumumab, bortezomib, cyclophosphamide and dexamethasone (D-VCd) represents the current standard of care for most patients with previously untreated diagnosed AL amyloidosis. However, data guiding subsequent treatment following D-VCd are limited.
Methods: Patients initiated on frontline D-VCd between 01/2018 and 12/2022 and switched to a subsequent treatment for progression/rising serum free light chains (sFLC), suboptimal response [≤partial response], or toxicity,  were included. Patients with a planned autologous stem cell transplant (ASCT) after a very good partial response or better with D-VCd induction were excluded. Hematologic response was assessed from start of subsequent treatment and organ response was calculated from frontline treatment initiation using consensus definitions. Event-free survival (EFS) and overall survival (OS) were calculated from start of subsequent treatment to stopping treatment due to progression, suboptimal response or toxicity.
Results: Out of 119 patients treated with D-VCd, 28 patients received subsequent treatment and were included in the study cohort (Table). The median follow-up time from subsequent treatment was 17.9 months (95% CI: 16.3-26.4). Indications for initiating subsequent treatment were suboptimal response in 21 (75%) patients (mostly hematologic PR), progression/rising sFLC in 6 (21%) patients, and toxicity in 1 (4%) patient. Treatments utilized were heterogeneous (Table) with daratumumab-based combinations being the most common subsequent regimen (n=12; 43%) followed by ASCT ( n=7, 25%); 82% (23/29) demonstrated a deepening response. Median EFS was 14.3 months (95% CI: 10.3-NR), and 18-month OS rate was 89 %.
Conclusion: Treatments utilized post D-VCd are heterogeneous and demonstrate a deepening of response in majority of patients.



**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.**
Saurabh Zanwar, Mayo Clinic, Rochester, MN

**Main Body of the Abstract**
**Background:** Daratumumab, bortezomib, cyclophosphamide and dexamethasone (D-VCd) represents the current standard of care for most patients with previously untreated diagnosed AL amyloidosis. However, data guiding subsequent treatment following D-VCd are limited.
**Methods:** Patients initiated on frontline D-VCd between 01/2018 and 12/2022 and switched to a subsequent treatment for progression/rising serum free light chains (sFLC), suboptimal response [≤partial response], or toxicity,  were included. Patients with a planned autologous stem cell transplant (ASCT) after a very good partial response or better with D-VCd induction were excluded. Hematologic response was assessed from start of subsequent treatment and organ response was calculated from frontline treatment initiation using consensus definitions. Event-free survival (EFS) and overall survival (OS) were calculated from start of subsequent treatment to stopping treatment due to progression, suboptimal response or toxicity.
**Results:** Out of 119 patients treated with D-VCd, 28 patients received subsequent treatment and were included in the study cohort (**Table**). The median follow-up time from subsequent treatment was 17.9 months (95% CI: 16.3-26.4). Indications for initiating subsequent treatment were suboptimal response in 21 (75%) patients (mostly hematologic PR), progression/rising sFLC in 6 (21%) patients, and toxicity in 1 (4%) patient. Treatments utilized were heterogeneous (**Table**) with daratumumab-based combinations being the most common subsequent regimen (n=12; 43%) followed by ASCT ( n=7, 25%); 82% (23/29) demonstrated a deepening response. Median EFS was 14.3 months (95% CI: 10.3-NR), and 18-month OS rate was 89 %.
**Conclusion:** Treatments utilized post D-VCd are heterogeneous and demonstrate a deepening of response in majority of patients.



Treatment Patterns for AL Amyloidosis after Frontline Daratumumab, Bortezomib, Cyclophosphamide and Dexamethasone Treatment Failures PA151 (#184)

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.