Minimal Residual Disease as a Possible Predictive Factor for Relapse in Patients With AL Amyloidosis

This protocol will assess AL amyloidosis patients who achieve a CR or VGPR to first-line
therapy for evidence of MRD by Q-PCR, NGS, and plasma protein analysis by mass spectrometry
using marrow cells obtained annually at times of standard clinical evaluations.

A bone marrow aspirate sample from diagnosis will be used to create a baseline profile of
each patient's disease. This sample will allow the investigators to create the primer-probe
sets required for MRD testing by Q-PCR, which will be conducted after the patient has
achieved a CR or VGPR. A baseline bone marrow biopsy sample will either be taken at the time
of consent or can be taken from storage if the patient has previously consented to have their
marrow cells banked for research purposes. An extra 15 mL of aspirate will be taken from
their diagnostic bone marrow biopsy, which is routinely conducted on newly diagnosed patients
for clinical purposes. Annual bone marrow aspirates will not be taken for research purposes
until after the patient has responded. Patients will remain on protocol, but only begin MRD
testing after achieving a CR or VGPR to first-line therapy at which point annual marrow
collections for MRD testing will begin. In the event the patient does not reach a CR or VGPR
to first-line therapy, the baseline bone marrow aspirate from diagnosis will be discarded.

Patients who choose to allow their marrow to be used in this study will sign a consent form
specifically for this study. At the time of consent, three green top tubes of peripheral
blood will be obtained for WGS of non-tumor cells. No further blood samples will be required
for this study. After achieving a CR or VGPR, patients will be completely re-staged as is
standard of care at annual intervals. Samples to test for the presence of MRD in their
marrows will be obtained at these times of clinical re-staging for up to 3 years after their
response to therapy. Both blood and bone marrow samples for this study will be immediately
taken to an on-site laboratory where they will be briefly stored before testing. This will
ensure no study samples interfere with routine clinical care.

In order to test for the presence of MRD, three techniques will be used: Q-PCR, WGS, and
plasma protein analysis by mass spectrometry. Both Q-PCR and WGS will use genomic DNA from
marrow aspirate samples. To make primer-probe sets for Q-PCR, bone marrow samples from
baseline will be used to create individualized primer-probe sets that can recognize the
genetically unique LC gene that causes each patient's disease. To perform WGS, genomic DNA
will be supplied to the core genetics laboratory for creation of a library and multiplex next
generation sequencing. To perform plasma protein analysis, plasma will be isolated from a
portion of each subject's peripheral blood and bone marrow aspirate samples in an on-site
laboratory. Each subject's de-identified LC gene sequence and their de-identified plasma
samples will then be sent to Memorial Sloan-Kettering Cancer Center (MSKCC) for mass
spectrometry to look for fragmentary protein sequences associated with the culprit LC gene of
each subject.

After reaching a CR or VGPR, at annual evaluations for up to 3 years, the genomic DNA from
the research sample of bone marrow collected during standard of care clinical procedures will
be used to confirm maintenance of response by testing for the presence of MRD with each of
the 3 methods (Q-PCR, WGS, and plasma protein analysis) noted above. Marrow material
collected for the purposes of this study will not be stored after analysis, and primer-probe
set design will be conducted entirely within Tufts Medical Center. Any marrow samples not
fully consumed during analysis will be destroyed.

By using these three methods this protocol will determine whether one method is superior to
the others and whether the three methods produce results that correlate with each other. The
decision to discontinue participation in MRD testing will be made by the patient and the
physician on an individual basis. Patients who have relapse or hematologic progression of
disease during the three year period by standard blood and urine tests will no longer have
testing for MRD.

Inclusion Criteria:

- Patients with AL amyloidosis at Tufts Medical Center who have baseline bone marrow
samples available and achieve a CR or VGPR to treatment. Patients may consent and
register at diagnosis and have a baseline marrow collected at the time of consent; or
patients may consent during therapy prior to achieving a response, if they have
previously banked marrow cells for research.

Exclusion Criteria:

- Patients who do not have available baseline bone marrow samples.