The Food and Drug Administration (FDA) have approved encorafenib in combination with cetuximab for the treatment of adult patients with metastatic colorectal cancer (CRC) with a BRAF V600E mutation, detected by an FDA-approved test, after prior therapy.

Efficacy was evaluated in a randomised, active-controlled, open-label, multi-centre trial called BEACON CRC. 

Eligible patients were required to have BRAF V600E mutation-positive metastatic CRC (detected by the Qiagen therascreen® BRAF V600E RGQ PCR kit) with disease progression after one or two prior regimens.

A total of 220 patients were randomised to encorafenib (300 mg orally once daily) in combination with cetuximab and 221 patients were randomised to the control arm of either irinotecan or FOLFIRI with cetuximab.

The major efficacy outcome measure was overall survival (OS).

Additional efficacy outcome measures included progression-free survival (PFS), overall confirmed response rate (ORR), and duration of response (DoR).

ORR and DoR were assessed by blinded independent central review in the subset of the first 220 patients randomised to receive either encorafenib plus cetuximab or the control arm.

Median OS was 8.4 months (95% CI: 7.5, 11.0) in the encorafenib and cetuximab arm compared to 5.4 months (95% CI: 4.8, 6.6) in the control arm (HR 0.60; 95% CI: 0.45, 0.79; p=0.0003).

Median PFS was 4.2 months (95% CI: 3.7, 5.4) in the encorafenib and cetuximab arm compared to 1.5 months (95% CI: 1.4, 1.7) in the control arm (HR 0.40; 95% CI: 0.31, 0.52; p< 0.0001).

ORR was 20% (95% CI: 13%, 29%) and 2% (95% CI: 0%, 7%), respectively.

Median DOR was 6.1 months (95% CI: 4.1, 8.3) for the encorafenib and cetuximab arm and not reached (95% CI: 2.6, NR) in the control arm.

The most common adverse reactions (≥25%) for encorafenib with cetuximab were fatigue, nausea, diarrhoea, dermatitis acneiform, abdominal pain, decreased appetite, arthralgia, and rash.

The recommended encorafenib dose is 300 mg orally once daily in combination with cetuximab.

Source: The Food and Drug Administration (FDA)