Phase IV head-to-head randomized controlled trial comparing ingenol mebutate 0·015% gel with diclofenac sodium 3% gel for the treatment of actinic keratosis on the face or scalp.

Background: Ingenol mebutate (IngMeb) and diclofenac sodium (DS) are approved treatments for actinic keratosis (AK).

Objectives: To compare the efficacy and safety of IngMeb 0·015% gel with DS 3% gel (NCT02406014).

Methods: Patients with 4-8 visible, discrete AK lesions on the face/scalp in a 25 cm contiguous area of skin were randomized 1:1 to IngMeb once-daily for three consecutive days or DS twice-daily for 90 days. Patients with AK lesions at Week 8 following IngMeb were offered a second IngMeb course. Primary end point was complete clearance of AK lesions (AKCLEAR 100) at end of first treatment course (Week 8, IngMeb; Week 17, DS). Secondary end points included AKCLEAR 100 at end of last treatment course and Week 17; adverse events (AEs) were assessed at these time points. Patients completed treatment satisfaction questionnaires for medication (TSQM; Week 17).

Results: AKCLEAR 100 at end of first treatment course was higher with IngMeb (34%) vs. DS (23%; P = 0·006). AKCLEAR 100 at end of last IngMeb course (53%) and Week 17 (45%) was higher than DS (both P < 0·001). The most frequent AE was application-site erythema (IngMeb 19%; DS 12%). Treatment-related AE (TRAE) duration was shorter with IngMeb. TRAE withdrawals were lower for IngMeb (2%) vs. DS (6%). TSQM scores for global satisfaction (P < 0·001) and effectiveness (P = 0·002) were higher with IngMeb, as was dosing instruction adherence (≥ 90% vs. 70%).

Conclusions: AKCLEAR 100, patient treatment satisfaction and effectiveness were significantly higher with IngMeb compared with DS, demonstrating superiority of IngMeb for AK treatment on face/scalp.