In this trial, 61 cancer patients (31 lung, 16 CRC and 15 other malignancies), starting treatment with an EGFR-targeted agent (cetuximab or gefitinib), were randomized to receive either tetracycline (500 mg/bid for 28 days) or placebo.41 The primary objective of the study was to compare the incidence of rash in patients treated with prophylactic tetracycline versus placebo. Here, EGFR is linked to cancer.