Inclusion Criteria:

- Histologically or cytologically confirmed diagnosis of squamous cell carcinoma of the
head and neck (SCCHN).

- Recurrent and/or metastatic SCCHN, not suitable for local therapy.

- At least 1 measurable lesion either by computerized tomography (CT) scan or magnetic
resonance imaging (MRI) (according to RECIST 1.0).

- Karnofsky performance status (KPS) of ≥ 70 / Eastern Cooperative Oncology Group
performance status (ECOG PS) of 0 or 1 at trial entry.

Exclusion Criteria:

- Prior systemic chemotherapy, except if given as part of a multimodal treatment for
locally advanced disease which was completed more than 2 months prior to trial entry.

- Nasopharyngeal carcinoma.

- Medical history of diagnosed interstitial lung disease.

- Known hypersensitivity against any of the components of the trial treatment.

- Previous treatment with experimental or non-approved epidermal growth factor receptor
(EGFR) targeting therapy or experimental or nonapproved EGFR signal transduction
inhibitors (prior treatment with cetuximab is allowed).

- Relevant cardiovascular co-morbidities.

- Concomitant chronic systemic immune therapy, or hormonal therapy as cancer therapy,
steroid use ≥ 10 mg prednisone equivalent.

- Known human immunodeficiency virus (HIV) positivity, active hepatitis C, or active
hepatitis B.