A Study of Subcutaneous (SC) AMG 701 in Participants With Relapsed or Refractory Multiple Myeloma (RRMM)

ABSTRACT

ConditionRelapsed/Refractory Multiple Myeloma

InterventionDrug AMG 701;Drug AMG 701

Primary outcome:Number of participants who experience dose-limiting toxicities (DLTs);Number of participants who experience one or more treatment-emergent adverse events (TEAEs);Number of participants who experience one or more treatment-related TEAEs;Number of participants with abnormal changes in vital signs;Number of participants with abnormal changes in electrocardiograms (ECGs) findings;Number of participants with abnormal changes in clinical laboratory tests

Criteria
Inclusion Criteria

- Participant has provided informed consent prior to initiation of any study specific
activities/procedures.

- Age 18 years or older at the time of signing the informed consent.

- Relapsed or relapsed and refractory multiple myeloma according to International
Myeloma Working Group (IMWG) criteria.

- Participants must have received = 3 prior therapies that must include all approved and
available therapies deemed eligible by the investigator, including at a minimum, a
proteasome inhibitor (PI), an immunomodulatory drug (IMiD), and a CD38-directed
antibody. Note Participants may have received prior treatment targeting BCMA that is
not AMG 701.

- Participants must have measurable disease, defined by 1 or more of the following at
time of screening

- A serum M protein = 0.5 g/dL measured by serum protein electrophoresis (SPEP)

- Urinary M protein excretion = 200 mg/24 hours

- Involved serum free light chain (sFLC) measurement = 10 mg/dL, provided that SFLC
ratio is abnormal as per IMWG response criteria

- Eastern Cooperative Oncology Group (ECOG) Performance Status of = 2.

- Life expectancy of at least 3 months as per investigator's judgment at time of
screening

- Hematological function without transfusion support as follows

- Absolute neutrophil count = 1.0 x 10^9/L (without growth factor support)

- Platelet count = 50 x 10^9/L (without transfusions within 7 days from screening
assessment)

- Hemoglobin = 8.0 g/dL (transfusions permitted no later than 48 hours before
screening)

- Renal function as follows

Calculated or measured creatinine clearance = 30 mL/min using

- The Cockcroft-Gault equation OR

- Via 24-hour urine collection with plasma and urine creatinine concentrations

- Hepatic function as follows

- Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) = 2.5 x upper
limit of normal (ULN)

- Total bilirubin (TBIL) < 1.5 x ULN (unless considered due to Gilbert's syndrome)

- Cardiac function as follows

- Left ventricular ejection fraction = 50% as assessed by transthoracic echocardiogram
(TTE) or multigated acquisition (MUGA) scan.

- Serum sodium, potassium, phosphorus, calcium, and magnesium must be within normal
range or if outside normal range must have resolved to Common Terminology
Criteria for Adverse Events (CTCAE) version 5.0 grade 1 within 7 days of day 1.
Participants not meeting these inclusion criteria may be treated with replacement
therapy and re-screened up to 2 times at the discretion of the investigator.

- Participants with prior COVID-19 infection or history of cardiovascular disease
including coronary artery disease, significant valvular disease, cardiac
arrhythmia, cardiomyopathy, or history of cardiac toxicity with prior therapy
must have a cardiology consultation during screening with a clinical management
plan during cytokine release syndrome (CRS) prior to cycle 1 day 1 therapy.

- Participants with a history of COVID-19 infection must be discussed with the
medical monitor prior to enrollment. Participants with a history of COVID-19
infection must have a negative quantitative polymerase chain reaction (PCR) test
prior to enrollment.

Exclusion Criteria

- Known central nervous system involvement by multiple myeloma.

- Recent history of primary plasma cell leukemia (within last 6 months prior to
enrollment) or evidence of primary or secondary plasma cell leukemia at the time of
screening.

- Waldenström macroglobulinemia, POEMS syndrome (polyneuropathy, organomegaly,
endocrinopathy, monoclonal protein, skin changes), or amyloidosis (participants with
multiple myeloma with asymptomatic amyloid plaques found on biopsy would be eligible
if all other criteria are met).

- History or evidence of any of the following cardiovascular disorders

- Active congestive heart failure (New York Heart Association Class III to IV)

- Symptomatic ischemia

- Uncontrolled arrhythmias

- Screening ECG with corrected QT interval (QTc) of > 470 msec

- Myocardial infarction within 12 months prior to study day 1

- History of malignancy other than multiple myeloma within the past 3 years with the
following exceptions

- Malignancy treated with curative intent and with no known active disease present
for at least 1 year before enrollment and felt to be at low risk for recurrence
by the treating physician.

- Adequately treated cervical carcinoma in situ without evidence of disease.

- Breast ductal carcinoma in situ with full surgical resection (ie, negative
margins) and without evidence of disease

- Prostate cancer with a Gleason score < 7 with undetectable prostate specific
antigen over 12 months

- Treated medullary or papillary thyroid cancer

- Adequately treated urothelial papillary noninvasive carcinoma or carcinoma in
situ

- Similar neoplastic conditions with an expectation of > 95% 5-year disease-free
survival

- Adequately treated non-melanoma skin cancer or lentigo maligna without evidence
of disease.

- Clinically uncontrolled chronic or ongoing bacterial, fungal, viral, or other
infectious disease at study day 1 or within 14 days before study day 1.

- Positive result for human immunodeficiency virus (HIV).

- Active hepatitis B and C based on the following results:

- Positive for hepatitis B surface antigen (HepBsAg) (indicative of chronic
hepatitis B or recent acute hepatitis B)

- Negative HepBsAg and positive for hepatitis B core antibody Either a positive
hepatitis B surface antibody or a negative hepatitis B virus DNA by PCR result is
necessary for enrollment

- Positive hepatitis C virus antibody Negative hepatitis C virus RNA by PCR result
is necessary for enrollment

- Unresolved toxicities from prior anticancer therapy, defined as not having resolved to
CTCAE version 5.0 grade 1 or to levels dictated in the eligibility criteria with the
exception of grade 2 peripheral neuropathy, alopecia or toxicities from prior
anticancer therapy that are considered irreversible (defined