Paclitaxel and Pembrolizumab in Treating Patients With Refractory Metastatic Urothelial Cancer

PRIMARY OBJECTIVES:

I. To estimate the overall response rate (ORR) of pembrolizumab combined with paclitaxel.

SECONDARY OBJECTIVES:

I. To determine the safety and tolerability of pembrolizumab combined with paclitaxel.

II. To calculate the progression-free survival (PFS) rate at 6 months.

TERTIARY OBJECTIVES:

I. To determine the immune effects of pembrolizumab combined with paclitaxel. II. To
associate immune effects with tumor response. III. To explore changes in immune-regulatory
micro ribonucleic acids (RNAs) as biomarkers of response.

OUTLINE:

Patients receive pembrolizumab intravenously (IV) over 30 minutes on day 1 and paclitaxel IV
over 60 minutes on day 1 and 8. Treatment repeats every 21 days for 8 courses in the absence
of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed up within 30 days and then every 3
months for 1 year.

Inclusion Criteria:

- Patients diagnosed with platinum-refractory metastatic urothelial cancer that is
measureable based on Response Evaluation Criteria in Solid Tumors (RECIST) criteria
1.1

- At least 1 prior chemotherapy regimen containing cisplatin or carboplatin

- Patient must be willing to provide tissue from a newly obtained core or excisional
biopsy of a tumor lesion; newly-obtained is defined as a specimen obtained up to 12
weeks (84 days) prior to initiation of treatment on day 1; archived specimen can be
used for subjects in whom newly-obtained samples cannot be provided

- Performance status of 0 or 1 on the Eastern Cooperative Oncology Group (ECOG)
performance scale

- Absolute neutrophil count (ANC) >= 1,500 /mcL

- Platelets >= 80,000 / mcL

- Hemoglobin >= 9 g/dL without transfusion dependency

- Serum creatinine =< 1.5 X upper limit of normal (ULN) OR measured or calculated
creatinine clearance (glomerular filtration rate [GFR] can also be used in place of
creatinine or creatinine clearance rate [CrCl]) >= 35 mL/min for subject with
creatinine levels > 1.5 X institutional ULN

- Serum total bilirubin =< 1.5 X ULN OR direct bilirubin =< ULN for subjects with total
bilirubin levels > 1.5 ULN

- Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase [SGOT]) and
alanine aminotransferase (ALT) (serum glutamate pyruvate transaminase [SGPT]) =< 2.5 X
ULN OR =< 5 X ULN for subjects with liver metastases

- Albumin >= 2.5 mg/dL

- Female subject of childbearing potential should have a negative urine or serum
pregnancy within 72 hours prior to receiving the first dose of study medication; if
the urine test is positive or cannot be confirmed as negative, a serum pregnancy test
will be required

- Female subjects of childbearing potential should be willing to use 2 methods of birth
control or be surgically sterile, or abstain from heterosexual activity for the course
of the study through 120 days after the last dose of study medication; subjects of
childbearing potential are those who have not been surgically sterilized or have not
been free from menses for > 1 year

- Male subjects should agree to use an adequate method of contraception starting with
the first dose of study therapy through 120 days after the last dose of study therapy

- Ability to understand and the willingness to sign an Institutional Review Board
(IRB)-approved informed consent document

Exclusion Criteria:

- Currently receiving or has had treatment with an investigational agent or used an
investigational device within 4 weeks of study day 1

- Anti-cancer monoclonal antibody (mAb) within 4 weeks prior to study day 1 or who has
not recovered (i.e., =< grade 1 or at baseline) from adverse events due to agents
administered more than 4 weeks earlier

- Chemotherapy, targeted small molecule therapy, or radiation therapy within 2 weeks
prior to study day 1 or who has not recovered (i.e., =< grade 1 or at baseline) from
adverse events due to a previously administered agent

- Note: Subjects with =< grade 2 neuropathy are an exception to this criterion and
may qualify for the study

- Note: If subject received major surgery, they must have recovered adequately from
the toxicity and/or complications from the intervention prior to starting therapy

- Prior therapy with an anti-programmed cell death 1 (PD-1), anti-programmed cell
death-ligand 1 (PD-L1), or anti-programmed cell death-ligand 2 (PD-L2) agent

- Hypersensitivity to pembrolizumab, any of its excipients, paclitaxel, or any of its
excipients

- Diagnosis of immunodeficiency or is receiving systemic steroid therapy or any other
form of immunosuppressive therapy within 7 days prior to the first dose of trial
treatment

- Known history of active TB (Bacillus tuberculosis)

- Known additional malignancy that is progressing or requires active treatment;
exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the
skin that has undergone potentially curative therapy or in situ cervical cancer

- Known active central nervous system (CNS) metastases and/or carcinomatous meningitis;
subjects with previously treated brain metastases may participate provided they are
stable (without evidence of progression by imaging for at least four weeks prior to
the first dose of trial treatment and any neurologic symptoms have returned to
baseline), have no evidence of new or enlarging brain metastases, and are not using
steroids for at least 7 days prior to trial treatment; this exception does not include
carcinomatous meningitis which is excluded regardless of clinical stability

- Active autoimmune disease that has required systemic treatment in the past 2 years
(i.e. with use of disease modifying agents, corticosteroids or immunosuppressive
drugs); replacement therapy (eg., thyroxine, insulin, or physiologic corticosteroid
replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a
form of systemic treatment

- Known history of, or any evidence of active, non-infectious pneumonitis

- Active infection requiring systemic therapy

- History or current evidence of any condition, therapy, or laboratory abnormality that
might confound the results of the trial, interfere with the subject's participation
for the full duration of the trial, or is not in the best interest of the subject to
participate, in the opinion of the treating investigator

- Known psychiatric or substance abuse disorders that would interfere with cooperation
with the requirements of the trial

- Pregnancy or breastfeeding, or expecting to conceive or father children within the
projected duration of the trial, starting with the pre-screening or screening visit
through 120 days after the last dose of trial treatment

- Known history of human immunodeficiency virus (HIV) (HIV 1/2 antibodies)

- Known active hepatitis B (e.g., hepatitis B virus surface antigen [HBsAg] reactive) or
hepatitis C (e.g., hepatitis C virus [HCV] ribonucleic acid [RNA] [qualitative] is
detected)

- Received a live vaccine within 30 days of planned start of study therapy

- Note: Seasonal influenza vaccines for injection are generally inactivated flu
vaccines and are allowed; however intranasal influenza vaccines (e.g., Flu-Mist®)
are live attenuated vaccines, and are not allowed