A Study of MEHD7945A in Combination With Cisplatin and 5-FU or Paclitaxel and Carboplatin on Patients With Recurrent/Metastatic Squamous Cell Carcinoma of the Head and Neck

Inclusion Criteria:

- Histologically confirmed recurrent or metastatic squamous cell carcinoma of the head
and neck (R/M SCCHN) of mucosal origin (e.g., oral cavity, oropharynx, hypopharynx,
larynx) that is not amenable to further curative local therapy (e.g., surgery,
radiation including re-irradiation) (1L R/M)

- Patients with unknown primary SCCHN presumed to be of head and neck mucosal origin
are eligible if they meet all other entry criteria

- For patients who present with de novo metastatic disease, no prior systemic
chemotherapy is allowed

- For patients with recurrent SCCHN, prior systemic therapy is allowed if it was given
as part of induction or definitive therapy. If patients have received prior combined
chemo-radiation therapy, they must be off therapy for at least 3 months

- Consent to provide archival tumor tissue for biomarker testing

- Life expectancy greater than or equal to (>/=) 12 weeks

- Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2

- Disease that is measurable per modified Response Evaluation Criteria in Solid Tumors
(RECIST) v1.1

- Adequate bone marrow and organ function

Exclusion Criteria:

- Nasopharyngeal cancer

- Prior treatment with an investigational or approved agent for the purpose of
inhibiting epidermal growth factor receptor (HER) family members

- This includes, but is not limited to, cetuximab, panitumumab, erlotinib,
gefitinib, and lapatinib.

- Prior treatment with an epidermal growth factor receptor (EGFR) inhibitor is
allowed if it was administered as part of definitive therapy for locally
advanced disease and completed/terminated >/= 3 months before study enrollment.

- Major surgical procedure within 4 weeks prior to Day 1

- Leptomeningeal disease as the only manifestation of the current malignancy

- Active infection requiring antibiotics

- Active autoimmune disease that is not controlled by nonsteroidal anti-inflammatory
drugs (NSAIDs)

- Symptomatic hypercalcemia requiring continued use of bisphosphonate therapy

- Current severe, uncontrolled systemic disease

- History of cardiac heart failure of New York Heart Association Class II or greater or
serious cardiac arrhythmia requiring treatment (except for atrial fibrillation and
paroxysmal supraventricular tachycardia)

- History of myocardial infarction within 6 months prior to Cycle 1, Day 1, or history
of unstable angina

- Clinically significant history of liver disease, including viral or other hepatitis,
current alcohol abuse, or cirrhosis

- History of bleeding diathesis or coagulopathy other than that due to anticoagulation
therapy

- Clinically significant GI bleeding within 6 months prior to Cycle 1, Day 1

- History of interstitial lung disease (ILD)

- History of severe (Grade 3 or 4) allergic or hypersensitivity reaction to therapeutic
antibodies that required discontinuation of therapy

- Known human immunodeficiency virus (HIV) infection

- Untreated/active central nervous system (CNS) metastases (progressing or requiring
anticonvulsants or corticosteroids for symptomatic control)

- Pregnancy (positive pregnancy test) or lactation

- Malignancies other than SCCHN within 5 years prior to enrollment, with the exception
of adequately treated basal or squamous cell skin cancer and carcinoma in situ of the
cervix or skin (e.g., melanoma in situ) or indolent prostate cancer