Phase II Trial Evaluating the Efficacy of Palbociclib in Combination With Carboplatin for the Treatment of Unresectable Recurrent or Metastatic Head and Neck Squamous Cell Carcinoma

Inclusion Criteria:

- Histologically documented progressive squamous cell head and neck cancer with or
without metastases, not amenable to curative treatment; or the patient has documented
refusal of curative treatment.

- ECOG performance status of 0-2. Eastern Cooperative Oncology Group Performance Status:
an attempt to quantify cancer patients' general well-being and activities of daily
life. The score ranges from 0 to 5 where 0 is asymptomatic and 5 is death.

- Presence of measurable disease by CT scan per RECIST v1.1.

- Age ≥18 years.

- Life expectancy of ≥12 weeks.

- Women of childbearing potential must have a negative serum or urine pregnancy test at
time of screening and confirmed within 3 days prior to treatment. Women not of
child-bearing potential will be defined as all women older than age 50 and anovulatory
for 12 months.

- Signed and dated informed consent document indicating that the patient (or legally
acceptable representative) has been informed of all pertinent aspects of the trial
prior to enrollment.

- Willingness and ability to comply with scheduled visits, treatment plans, laboratory
tests, and other study procedures.

- Adequate organ and marrow function

Exclusion Criteria:

- Previous treatment with cytotoxic chemotherapy therapy in the recurrent/metastatic
setting. Previous treatment with non-cytotoxic agents in the recurrent/metastatic
setting is permitted. Gastrointestinal abnormalities causing impaired absorption
precluding administration of oral medications.

- Evidence of untreated or progressive brain metastases, spinal cord compression, or
carcinomatous meningitis.

- A serious uncontrolled medical disorder or active infection that would impair their
ability to receive study treatment.

- Dementia or significantly altered mental status that would prohibit the understanding
or rendering of informed consent and compliance with the requirements of this
protocol.

- Patients (male and female) having procreative potential who are not willing or not
able to use adequate contraception. Women who are pregnant or breast-feeding.

- Patients residing in prison.

- Prior experimental therapy within 30 days of enrollment.

- Availability of curative treatment option for the patient's cancer, whether surgery,
chemotherapy, radiation, or combination thereof, unless the patient has documented
refusal of curative treatment.

- Current use or anticipated inability to avoid use of drugs that are known strong
CYP3A4/5 inhibitors (atazanavir, boceprevir, conivaptan, clarithromycin, grapefruit or
grapefruit juice, indinavir, itraconazole, ketoconazole, nelfinavir, nefazodone,
posaconazole, ritonavir, saquinavir, telaprevir, telithromycin, voriconazole ).

- Current use or anticipated inability to avoid use of drugs that are known strong
CYP3A4/5 inducers (carbamazepine, dexamethasone, fosphenytoin, phenytoin,
phenobarbital, rifabutin, rifampin, rifapentine, St. John's wort).

- Patients with a history of severe allergic reaction to cisplatin or carboplatin