Tenofovir Alafenamide in Preventing Liver Complications in Participants With Current or Past Hepatitis B Virus Who Are Receiving Anti-Cancer Therapy for Solid Tumors

PRIMARY OBJECTIVES:

I. To compare the effect of prophylactic tenofovir alafenamide (TAF) therapy versus upon
indication TAF therapy on time-to-adverse liver outcomes of liver failure or liver-related
death in patients with chronic HBV infection (hepatitis B surface antigen positive [HBsAg+]
and antibody to hepatitis B core antigen positive [anti-HBc+]) receiving anti-cancer therapy
for solid tumors.

II. To compare the effect of upon indication TAF therapy versus usual care on time-to-adverse
liver outcomes of liver failure or liver-related death in patients with past HBV infection
(hepatitis B surface antigen negative [HBsAg-] and anti-HBc+) receiving anti-cancer therapy
for solid tumors.

SECONDARY OBJECTIVES:

I. Using time-to-event analysis, to compare the effect of TAF therapy versus upon indication
TAF therapy on HBV reactivation, on the combined endpoint of adverse liver outcomes (liver
failure or liver-related death) and HBV reactivation, and on HBV flare by arm in patients
with chronic HBV infection receiving anti-cancer therapy for solid tumors.

II. Using time-to-event analysis, to compare the effect of upon indication TAF therapy versus
usual care on HBV reactivation, on the combined endpoint of adverse liver outcomes (liver
failure or liver-related death) and HBV reactivation, and on HBV flare by arm in patients
with past HBV infection receiving anti-cancer therapy for solid tumors.

TRANSLATIONAL OBJECTIVES:

I. To compare baseline and changes in overall immune status and HBV-specific immune response
in patients with solid tumors and chronic or past HBV infection receiving anti-cancer
therapy, and to compare the differences in these immune responses by HBV reactivation status.

II. To identify demographic and clinical predictors and correlative immunologic biomarkers of
HBV reactivation after receipt of anti-cancer therapy in patients with solid tumors and
chronic or past HBV infection.

OUTLINE: Participants are randomized to 1 of 3 groups.

GROUP A (Cohorts 1a & 2a): Participants receive TAF orally (PO) once daily (QD) immediately
or within 28 days after initial dose of chemotherapy. Treatment continues for up to 6 months
after the last dose of chemotherapy or a maximum of 24 months in the absence of disease
progression or unacceptable toxicity.

GROUP B (Cohorts 1b & 2b): Participants receive TAF PO QD after HBV reactivation during
chemotherapy. Treatment continues for up to 6 months after the last dose of chemotherapy or a
maximum of 24 months in the absence of disease progression or unacceptable toxicity.

GROUP C (Cohort 3): Participants receive TAF PO QD at the discretion of the physician during
usual care. Treatment continues for up to 6 months after discontinuation of usual care or a
maximum of 24 months in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, participants are followed up for up to 24 months.

Inclusion Criteria:

- Patients must be diagnosed with stage I-III solid tumor malignancy; patients with only
carcinoma in situ or with stage IV disease are excluded

- Patients must not have been diagnosed with a malignancy other than the current
malignancy within the past five years, with the exception of basal cell or squamous
cell skin cancer, in situ cervical cancer, or in situ breast cancer

- Patients must not have lymphoma, leukemia, or myeloma

- Patients must not have primary liver cancer, known cirrhosis, or evidence of any
malignancy that involves the liver

- Patients must be planning to receive systemic anti-cancer therapy (either single agent
or some combination of systemic cytotoxic therapy, systemic immunotherapy or systemic
targeted therapy) for this solid tumor

- Patients must not have been previously treated with the same anti-cancer therapy
regimen that is now anticipated; the anti-cancer therapy does not have to be
first-line therapy; prior and/or concurrent radiotherapy is allowed

- Patients must be registered =< 28 days prior to the planned start date of anti-cancer
therapy; if the patient has started systemic anti-cancer therapy, patient must be
registered =< 28 days after the initiation of first cycle of anti-cancer therapy or
prior to the second cycle of the anti-cancer therapy, whichever occurs earlier

- International normalized ratio (INR) must be completed =< 28 days prior to
registration; results must be in the institutional limits of normal

- Patients who have received prior anti-cancer therapy must have discontinued all
previous therapies (excluding planned anti-cancer therapy to occur in conjunction with
this study) >= 1 day prior to registration to this study

- Patients must not have had any cancer therapy regimen that includes anti-CD20

- Patients must not be receiving antiviral medications active against HBV, including:
adefovir, entecavir, lamivudine, telbivudine, tenofovir disoproxil fumarate, tenofovir
alafenamide (TAF), or any other Food and Drug Administration (FDA) approved agents for
the treatment of hepatitis B; patients who have previously received antiviral
medication must not have required any antiviral medication active against HBV >= 90
days prior to registration to this study

- Patients must not have had hematopoietic stem cell transplantation therapy

- Patients receiving any of the following medications must discontinue them (under the
supervision of their treating physician) prior to registration, and must not be
planning to take them during protocol therapy: acyclovir, aminoglycosides,
oxcarbazepine, phenobarbital, phenytoin, rifabutin, rifampin, rifapentine,
valacyclovir, high-dose nonsteroidal anti-inflammatory drugs (NSAIDs), (?high-dose?
based on package insert), and St. John?s wort

- Patients must have complete results for the following HBV tests done =< 30 days prior
to registration: HBsAg AND anti-HBc (total immunoglobulin [Ig] or IgG, but not IgM
only) AND hepatitis B surface antibody (anti-HBs); for the anti-HBs test, quantitative
or qualitative (including ?indeterminate?) results are allowable

- Patients must have tested positive for HBsAg or anti-HBc (total Ig, IgG, but not IgM)
and must have baseline HBV deoxyribonucleic acid (DNA) completed =< 90 days prior to
registration

- Complete blood count (CBC) must be completed =< 28 days prior to registration; results
do not need to be in the institutional limits of normal

- INR must be completed within 28 days prior to registration; results must be in the
normal range

- Alanine aminotransferase (ALT) must be obtained =< 28 days prior to registration; ALT
must be within normal limits (> institutional lower limit of normal [ILLN] and <
institutional upper limit of normal [IULN]) for the institution

- Total bilirubin must be obtained =< 28 days prior to registration; total bilirubin
must be within normal limits (> ILLN and < IULN) for the institution

- Creatinine must be obtained =< 28 days prior to registration; creatinine must be
within normal limits (> ILLN and < IULN) for the institution

- Patients must not have known current active hepatitis C infection (HCV); active HCV is
defined by a detectable HCV ribonucleic acid (RNA) level

- Patients must not have a history of human immunodeficiency (HIV) infection; all
patients must have HIV testing completed =< 365 days prior to registration

- Patients must have Zubrod performance status of 0-2

- Patients must be able to swallow tablets orally

- Patients must not be pregnant or nursing, as the safety of the study drug in pregnant
and nursing women has not been established; women/men of reproductive potential must
have agreed to use an effective contraceptive method; a woman is considered to be of
"reproductive potential" if she has had menses at any time in the preceding 12
consecutive months; in addition to routine contraceptive methods, "effective
contraception" also includes heterosexual celibacy and surgery intended to prevent
pregnancy (or with a side-effect of pregnancy prevention) defined as a hysterectomy,
bilateral oophorectomy or bilateral tubal ligation; however, if at any point a
previously celibate patient chooses to become heterosexually active during the time
period for use of contraceptive measures outlined in the protocol, he/she is
responsible for beginning contraceptive measures

- Patients must have specimens collected for submission as outlined

- Patients must be offered the opportunity to participate in optional translational
medicine studies as outlined

- Patients may have concurrent participation in other clinical trials that entail
cytotoxic, immunotherapy, targeted therapy; surgical treatment; radiotherapy
treatment; or any combination thereof

- Patients must be informed of the investigational nature of this study and must sign
and give written informed consent in accordance with institutional and federal
guidelines

- As a part of the Oncology Patient Enrollment Network (OPEN) registration process the
treating institution's identity is provided in order to ensure that the current
(within 365 days) date of institutional review board approval for this study has been
entered in the system