Trial of Venetoclax (ABT-199) and Dexamethasone for Relapsed or Refractory Systemic AL Amyloidosis

The study is being conducted to determine the safety, tolerability and maximum tolerated dose
of Venetoclax and dexamethasone in relapsed or refractory amyloid light chain (AL)
amyloidosis patients. AL amyloidosis is a disease involving cells called plasma cells that
make antibodies as part of your immune system. These cells are not functioning the way they
are supposed to and they start to produce abnormal fragments of antibodies that are toxic to
your body and can form amyloid. The antibody fragments are called "light chains." They can
cause damage to organs, especially the kidneys, heart, skin, liver, and lungs.

Researchers are looking for ways to stop the light chains from being formed to treat the
disease. Under some circumstances, patients will receive chemotherapy drugs in order to
manage the disease. However, researchers do not know what the best treatment is for relapsed
AL amyloidosis, so the researchers are testing new drugs or new combinations of drugs to see
what will work best with the least side effects.

The researchers want to find out if Venetoclax (ABT-199) in addition to dexamethasone will
reduce or eliminate AL amyloidosis plasma cells. In this study, varying doses of Venetoclax
will be given to determine the maximum tolerated and safe dose for further study. The
researchers may also gain a better understanding of whether Venetoclax and dexamethasone can
counter the plasma cell disease that causes AL amyloidosis.

Inclusion Criteria:

- Histologic diagnosis of AL amyloidosis, confirmed by positive Congo red stained
biopsy, with evidence of measurable clonal disease according that requires active
treatment

- Eastern Cooperative Oncology Group (ECOG) status of 0 to 2

- Relapsed or refractory after at least 1 prior therapy for AL amyloidosis and, in the
investigator's opinion, require further treatment. Participants with a history of
autologous stem cell transplantation must have adequate blood counts independent of
growth factor support and have recovered from any transplant-related toxicities and be
at least 100 days post-autologous transplant.

- Less than 30% plasma cells in the bone marrow biopsy and no bone lesions or
hypercalcemia.

- The pre-screening test of CD138+ patient marrow plasma cells must show that the
patient's CD138+ plasma cells have an apoptosis ratio of Venetoclax treated over
untreated cells of greater than 1.4.

- Objective, measurable organ involvement. Skin purpura, carpal tunnel syndrome, or the
presence of vascular amyloid on a bone marrow biopsy alone are not sufficient to meet
criteria for "symptomatic organ involvement". Patients may have any of the following
amyloid-related organ involvement as defined below:

1. Renal: albuminuria higher than 0.5 g/day in a 24-hour urine collection.

2. Cardiac: involvement is defined as the presence of a mean left ventricular wall
thickness on echocardiogram more than 12 mm in the absence of a history of
hypertension or valvular heart disease, or unexplained low voltage (< 0.5 mV) on
electrocardiogram; or an NT-proBNP > 332 ng/L in CKD 1 or 2 patients or a BNP >
100ng/L in those who are CKD3.

3. Hepatic: hepatomegaly on physical examination with alkaline phosphatase > 1.5 X
the upper limit of normal (ULN).

4. Autonomic or peripheral neuropathy: based on clinical history, autonomic
dysfunction with orthostasis, symptoms of nausea or dysgeusia, gastric atony by
gastric emptying scan, diarrhea or constipation, or abnormal sensory and/or motor
findings on neurologic examination.

- AL Amyloidosis Cardiac Risk stage I, II or IIIa disease. Staging system defined by:
NT-proBNP cut off of < 332 pg/mL and troponin I cut-off of < 0.10 ng/mL as thresholds
for stages I, II and III; NT-proBNP < 8500 for stage IIIa.

1. Stage I, both under threshold;

2. Stage II, either troponin or NT-proBNP [but not both] over threshold;

3. Stage III, both over threshold;

4. Stage IIIa, both over threshold but NT-proBNP < 8500 pg/ml.

- Clinical laboratory values as specified below before the first dose of study drug:

1. Echocardiographic ejection fraction > 45% within 28 days before the first dose of
study drug.

2. Within the 3 days of the first dose of study drug: i. Platelet count > 75 x
109/L; ii. Neutrophil count > 1.0 x 109/L; iii. Total bilirubin < 2 x ULN; iv.
Alkaline phosphatase < 5 x ULN; v. Alanine aminotransferase (ALT) and aspartate
aminotransferase (AST) < 3 x ULN; vi. eGFR > 30 mL/min/1.73 m2

- Female patients who are postmenopausal for at least 1 year before the screening visit,
OR are surgically sterile, OR, if they are of childbearing potential, agree to
practice 2 effective methods of contraception, at the same time, from the time of
signing the informed consent through 30 days after the last dose of study drug, or
agree to completely abstain from heterosexual intercourse.

- Male patients, even if surgically sterilized (ie, status post vasectomy), who agree to
practice effective barrier contraception during the entire study treatment period and
through 30 days after the last dose of study drug, OR agree to completely abstain from
heterosexual intercourse.

- Voluntary written consent must be given before performance of any study-related
procedure not part of standard medical care with the understanding that consent may be
withdrawn by the patient at any time without prejudice to future medical care.

Exclusion Criteria:

- Treatment with any investigational products within 28 days before the first dose of
study drug.

- Requirement for other concomitant chemotherapy, immunotherapy, radiotherapy, or any
ancillary therapy considered to be investigational.

- Failure to have fully recovered (ie, > Grade 1 toxicity) from the effects of prior
chemotherapy regardless of the interval since last treatment.

- Active fungal infection requiring continued therapy.

- Cardiac system:

1. QTc > 470 milliseconds (msec) on a 12 lead ECG obtained during the Screening
period. If a machine reading is above this value, the ECG should be reviewed by a
qualified reader and confirmed on a subsequent ECG.

2. AL Amyloidosis Risk Stage IIIb disease. Stage IIIb is defined by NT-proBNP > 8500
pg/mL and troponin I > 0.10 ng/mL.

3. New York Heart Association (NYHA) classification III or IV.

4. Enzyme-documented myocardial infarction within 6 months before enrollment.

5. Chronic atrial fibrillation.

6. Grade 2 or 3 atrioventricular (AV) block (Mobitz, Type I permitted).

7. Supine systolic blood pressure < 90 mmHg, or symptomatic orthostatic hypotension,
or a decrease in systolic blood pressure on standing of > 20 mm Hg in spite of
being treated for orthostatic hypotension.

8. History of a bleeding diathesis or currently receiving treatment with warfarin.
Patients are allowed to take aspirin.

- GI system:

1. Severe diarrhea (= Grade 3) not controllable with medication (such as octreotide)
or requires administration of total parenteral nutrition.

2. Known GI disease or GI procedure that could interfere with the oral absorption or
tolerance of study drug, including difficulty swallowing.

- Neurologic/ Social system:

1. Patients with > Grade 2 peripheral neuropathy or painful peripheral neuropathy on
clinical examination will be excluded.

2. Previous or ongoing psychiatric illness.

3. Social situations that would limit compliance with study requirements.

- Systemic infections:

1. Known to be human immunodeficiency virus (HIV)-positive.

2. Known to be hepatitis B surface antigen-positive or has known active hepatitis C
infection.

3. Uncontrolled infection requiring systemic antibiotics.

- Clinically overt multiple myeloma (bone marrow plasma cells > 30%) and bone lesions or
hypercalcemia.

- Patients with non-AL amyloidosis.

- Presence of uncontrolled autoimmune hemolytic anemia or thrombocytopenia, or of active
malignancy with the exception of non-melanoma skin cancer, cervical cancer, treated
early-stage prostate cancer provided that prostate-specific antigen is within normal
limit, or any completely resected carcinoma in situ.

- Female patients who are lactating or pregnant.

- Major surgery within 14 days before the first dose of study drug.

- Patients who are taking and are required to take any of the following agents that are
CYP3A inhibitors: Amiodarone, Erythromycin, Fluconazole, Itraconazole, Ketoconazole,
Miconazole, Diltiazem, Verapamil, Amprenavir, Fosamprenavir, Clarithromycin,
Telithromycin, Nefazodone, Atazanavir, Darunavir, Indinavir, Lopinavir, Nelfinavir,
Ritonavir, Saquinavir, Tipranavir.