Inclusion Criteria:

- Must be appropriate candidate for experimental therapy, as determined by
investigator, after available standard therapies have failed

- Have adequate organ function

- Prior Therapies: Systemic treatments: must have discontinued previous systemic
treatments for cancer and recovered from the acute effects of therapy. Participants
must have discontinued mitomycin-C or nitrosourea therapy at least 42 days and have
discontinued any cytotoxic therapies at least 28 days prior to study enrollment.
Radiation therapy and surgery: must be completed at least 4 weeks before study
enrollment

- Part A: Must have diagnosis of cancer that is advanced or metastatic

- Part B: Must have histologically confirmed squamous cell cancer of the head and neck
or must have squamous cell cancer of any tumor type

- Part C: Must have histological diagnosis of squamous cell cancer of the head and
neck, histological or cytological diagnosis of squamous non-small-cell lung cancer,
or histological diagnosis of Stage IIIB (N2 or N3) or Stage IV small cell cancer of
the anus that is not curable by local therapy

- Must be available during the duration of the study and willing to follow the study
procedures

- If participant is of reproductive potential, must agree to use medically approved
contraceptive precautions during the study and for three months following the last
dose of study drug

- If the participant is a female of childbearing potential, must have had a negative
serum or urine pregnancy test within 7 days of the first dose of study drug and must
not be breast feeding

Exclusion Criteria:

- Must not have taken an unapproved drug as treatment for any indication within the
last 28 days prior to starting study treatment

- Must not have an active symptomatic fungal, bacterial or viral infection, including
human immunodeficiency virus (HIV) or Hepatitis A, B, or C

- Must not have a serious heart condition, such as congestive heart failure, unstable
angina pectoris, or heart attack within the last three months

- Must not have systolic blood pressure <90 millimeters of mercury (mmHg) or recurrent
symptomatic orthostatic hypotension

- Must not have a family history of long QTc syndrome or be taking drugs known to cause
QTc prolongation or Torsades de Pointes

- Must not have a serotonin-secreting carcinoid tumor or a prior history of
drug-induced serotonin syndrome

- Must not have acute leukemia