Evaluating Combination Immunotherapy for Advanced Cholangiocarcinoma With Pembrolizumab and PEG-Intron

Pembrolizumab and Sylatron Administration:

Pembrolizumab has been evaluated at 2 mg/kg every 3 weeks (Q3W), 10 mg/kg Q3W, or 10 mg/kg
Q2W in multiple previous studies for different types of cancer, the response rate at higher
dose level seems not improved compared to that of lower dose level. With concerns of
increased toxicities from the combination pembrolizumab and sylatron therapy, the
pembrolizumab dose is selected to be 200mg administered every three weeks. The approved dose
of sylatron for melanoma is induction treatment at 6 μg/kg/week for 8 doses followed by 5
year of maintenance treatment at 3 μg/kg/week for up to 5 years. The approved dose of
sylatron for chronic hepatitis C infection in combination with ribavirin is 1.5μg/kg weekly
for 24 to 48 weeks.

Each cycle = 21 days or 3 weeks. Based on the approved dosage of sylatron, we decided to
treat patients at 200mcg weekly up to 12 weeks (3 weeks as single agent, and 9 weeks in
combination of pembrolizumab). Sylatron will start Cycle 1 Day 1 and continue on a weekly
basis. We have prepared to reduce the dose of sylatron to 120mcg weekly, or 60mcg weekly if
patients experience unacceptable toxicities at the higher dose level of sylatron.

Pembrolizumab will be administered intravenously as a 30 minute infusion at a dose of 200 mg
every 3 weeks starting Week 4. Pembrolizumab will start Cycle 2 Day 1 and continue every 3
weeks. All trial treatments will be administered on an outpatient basis.

Sites should make every effort to target infusion timing to be as close to 30 minutes as
possible. However, given the variability of infusion pumps from site to site, a window of -5
minutes and +10 minutes is permitted (i.e., infusion time is 30 minutes: -5 min/+10 min).

With concerns about toxicity while using long-term sylatron, if no additional benefit is seen
beyond 12 weeks of treatment on top of that expected from pembrolizumab alone, patients will
discontinue sylatron treatment after they have received 12 weeks of this therapy (3 weeks as
single agent and 9 weeks in combination with pembrolizumab). Pembrolizumab should be
continued in the absence of unacceptable toxicity (based on CTCAE v4) until disease
progression-based on RECIST 1.1. In patients who had responded to the combination therapy,
when patient shows disease progression while on single agent pembrolizumab treatment,
Sylatron may be resumed at the discretion of the site investigator after discussion with the
sponsor-investigator.

Inclusion Criteria:

Subject must meet all of the following applicable inclusion criteria to participate in this
study:

1. Be willing and able to provide written informed consent/assent for the trial.

2. Be at least 18 years of age on day of signing informed consent.

3. Patients must have received 1 line of prior systemic therapy for metastatic or
resectable disease (i.e. patients may have received adjuvant gemcitabine and then
later gemcitabine/cisplatin for recurrent metastatic disease)

4. Histological confirmation of cholangiocarcinoma.

5. Have measurable disease based on RECIST 1.1.

6. 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 6 weeks (42 days)
prior to initiation of treatment on Day 1. Subjects for whom newly obtained samples
cannot be provided (e.g. inaccessible or subject safety concern) may submit an
archived specimen only upon agreement from the sponsor-investigator.

7. Have a performance status of 0 or 1 on the Eastern Cooperative Oncology Group (ECOG)
Performance Scale.

8. Demonstrate adequate organ function:

Hematological:

- Absolute neutrophil count (ANC) ≥ 1,500 /μL

- Platelets ≥ 100,000 / μL

- Hemoglobin ≥ 9 g/dL or ≥ 5.6 mmol/L without transfusion or EPO dependency (within
7 days of assessment)

Renal:

- Serum creatinine OR Measured or calculated creatinine clearance ≤ 1.5 X upper
limit of normal (ULN) OR ≥ 60 mL/min for subject with creatinine levels

- (GFR can also be used in place of creatinine or CrCl) > 1.5 x institutional ULN

Hepatic:

- Serum total bilirubin ≤ 2.0 X ULN

- AST (SGOT) and ALT (SGPT) ≤ 3.0 X ULN OR ≤ 5 X ULN for subjects with liver
metastases

- Albumin > 2.5 mg/dL

Coagulation:

- International Normalized Ratio (INR) or Prothrombin Time (PT) ≤ 1.5 X ULN unless
subject is receiving anticoagulant therapy as long as PT or PTT is within
therapeutic range of intended use of anticoagulants

- Activated Partial Thromboplastin Time (aPTT) ≤ 1.5 X ULN unless subject is
receiving anticoagulant therapy as long as PT or PTT is within therapeutic range
of intended use of anticoagulants

9. 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.

10. Female subjects of childbearing potential should be willing to use adequate 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.

11. 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.

Exclusion Criteria:

The subject must be excluded from participating in the trial if the subject:

1. A history of anaphylaxis to peginterferon alfa-2b or interferon alfa-2b

2. Is currently participating and receiving study therapy or has participated in a study
of an investigational agent and received study therapy or used an investigational
device within 4 weeks of the first dose of treatment.

3. Has a 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.

4. Has a known history of active Bacillus Tuberculosis (TB)

5. Hypersensitivity to pembrolizumab or any of its excipients.

6. Has had a prior 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.

7. Has had prior 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.

8. Has a 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.

9. Has 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.

10. Has 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 (e.g., thyroxine, insulin, or physiologic corticosteroid
replacement therapy for adrenal or pituitary insufficiency, etc.) is not considered a
form of systemic treatment.

11. Has known history of, or any evidence of active, non-infectious pneumonitis.

12. Has an active infection requiring systemic therapy.

13. Has a 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 site investigator.

14. Has known psychiatric or substance abuse disorders that would interfere with
cooperation with the requirements of the trial.

15. Is pregnant 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.

16. Has received prior therapy with an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent.

17. Has a known history of Human Immunodeficiency Virus (HIV) (HIV 1/2 antibodies).

18. Has known active Hepatitis B without HBV treatment (HBV infection with ongoing HBV
treatment is allowed); has persistent chronic Hepatitis C infection (successfully
treated HCV infection is allowed).

19. Has 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.

20. Has history of bipolar disorder or major depression.

21. Has history of not tolerating interferon treatment.

22. Has known serious neuropsychiatric condition.