Analysis of Oral Mucositis in Patient's Undergoing Melphalan Conditioning and Autologous Stem Cell Transplant

This is an exploratory observational (non-therapeutic) study to collect blood and buccal
mucosal samples to evaluate RNA expression, assess bacterial colonization, and plasma
Melphalan concentrations in approximately 50 eligible patients.

All study samples will be collected from participants while they are hospitalized to receive
standard of care high-dose Melphalan (HDM) chemotherapy and autologous peripheral blood stem
cell transplantation (ASCT). Patients who receive this treatment are typically admitted the
day before HDM. The day after HDM, patients receive ASCT and remain hospitalized for
approximately 21 days, or until their absolute neutrophil count increases to at least 500
cells per mm3 and they are no longer considered neutropenic.

Patients will have blood samples collected for pharmacokinetic analysis at approximately 0
minutes (before infusion begins), 15 minutes (during the infusion), 30 minutes (at the end
of infusion), 60 minutes, 90 minutes, 120 minutes, and 180 minutes after the start of
Melphalan infusion.

A buccal swab will be done to collect mucosal bacterial samples using paper strips
(Periopaper) or a sterile cotton tipped swab brushed against the right and left buccal
mucosa for approximately 15-30 seconds at the following time points:

1. Within 24 hours PRIOR to administration of Melphalan

2. Day +3 AFTER transplantation

3. Upon development of OM (approximately on days +7-10)

4. Upon recovery of absolute neutrophil count (ANC) to greater than 500/mm3, or on
discharge, whichever occurs first, in patients who developed OM

A buccal scraping will be done for gene expression using a dermatologic curette taken from
the right and left buccal mucosa at the following time points:

1. Within 24 hours PRIOR to administration of Melphalan

2. Day +3 AFTER transplantation Note: Patients' mouths will be rinsed with Mary's Magic
mouthwash prior to the procedure for 15 seconds, which will allow for removal of food
particles, colonized bacteria and anesthetization of oral mucosa. During procedure, any
signs of patient discomfort will be monitored. If patient expresses discomfort,
additional oral topical anesthetic will be utilized to de-sensitive buccal mucosa.

Inclusion Criteria:

1. Patients with multiple myeloma (MM) or systemic light-chain amyloidosis who are
receiving high-dose Melphalan (HDM) and autologous peripheral blood stem cell
transplantation (ASCT).

2. Age is greater than 18 years old

3. Patients receiving a total Melphalan dose of 140-200 mg/m2 as the preparative regimen

4. No prior history of allogeneic stem cell transplantation

5. Patients otherwise meeting all standard institutional criteria for ASCT

Exclusion Criteria:

1. Patients who do not meet inclusion criteria