Panitumumab, a fully human monoclonal antibody targeting the epidermal growth factor receptor (EGFR), is approved in the United States and Europe for the treatment of refractory metastatic colorectal cancer (mCRC). Skin toxicities are the most common adverse events with EGFR inhibitors. This is the first study designed to examine differences between pre-emptive and reactive skin treatment for specific skin toxicities in patients with mCRC for any EGFR inhibitor.

Patients receiving panitumumab-containing therapy were randomly assigned 1:1 to pre-emptive or reactive treatment (after skin toxicity developed). Pre-emptive treatment included use of skin moisturizers, sunscreen, topical steroid, and doxycycline. The primary end point of the study was the incidence of protocol-specified >or= grade 2 skin toxicities during the 6-week skin treatment period. Quality of life (QOL) was assessed with the Dermatology Life Quality Index (DLQI).

Of 95 enrolled patients, 48 received pre-emptive treatment, and 47 received reactive treatment. The incidence of protocol-specified >or= grade 2 skin toxicities during the 6-week skin treatment period was 29% and 62% for the pre-emptive and reactive groups, respectively. Mean DLQI score change from baseline to week 3 was 1.3 points and 4.2 points in the pre-emptive and reactive groups, respectively.

The pre-emptive skin treatment regimen was well tolerated. The incidence of specific >or= grade 2 skin toxicities during the 6-week skin treatment period was reduced by more than 50% in the pre-emptive group compared with the reactive group. Patients in the pre-emptive group reported less QOL impairment than patients in the reactive group.