Randomized, double-blind, double-dummy, vehicle-controlled study of ingenol mebutate gel 0.025% and 0.05% for actinic keratosis

J Am Acad Dermatol. 2009 Jun;60(6):934-43. doi: 10.1016/j.jaad.2009.01.008.


Background: There is a need for improved medical approaches to the treatment of actinic keratosis. Ingenol mebutate, a diterpene ester extracted and purified from the plant Euphorbia peplus, is being evaluated as a topical therapy for actinic keratosis.

Objective: Assess the efficacy and safety of ingenol mebutate (formerly PEP005) gel at 3 dosing regimens for the treatment of actinic keratosis.

Methods: Patients with non-facial actinic keratoses applied vehicle gel for 3 days, ingenol mebutate gel, 0.025% for 3 days, or ingenol mebutate gel, 0.05% for 2 or 3 days, with an 8-week follow-up period.

Results: All 3 active treatments were significantly more effective than vehicle at clearing actinic keratosis lesions, with a dose response observed. The partial clearance rate (primary efficacy end point) for patients treated with ingenol mebutate gel ranged from 56.0% to 75.4% compared with 21.7% for vehicle gel (P = .0002 to P < .0001 vs vehicle). The complete clearance rate was also significantly higher (P < or = .0006) for patients in the ingenol mebutate gel treatment groups (range: 40.0% to 54.4%) compared with vehicle (11.7%), as was the baseline clearance rate (range: 42.0% to 57.9% for ingenol mebutate gel compared with 13.3% for vehicle, P < .0001 to .0007 vs vehicle). The median percentage reduction in baseline actinic keratosis lesions for patients treated with ingenol mebutate gel ranged from 75% to 100% compared with 0% for vehicle gel (P < .0001 vs vehicle). Active treatment was well tolerated at all dosages. The mechanism of action of this agent is the localized induction of necrosis followed by a transient inflammatory response, and this was manifested in most patients as transient local skin responses consisting primarily of erythema, flaking/scaling, and crusting. There was no evidence of treatment-related scarring.

Limitations: Local skin responses may have suggested active treatment to investigators.

Conclusions: Short-course, field-directed therapy with ingenol mebutate gel for actinic keratoses on non-facial sites seems to be effective with a favorable safety profile and potential benefits over topical agents that require a more prolonged course of treatment.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Topical
  • Adult
  • Aged
  • Aged, 80 and over
  • Diterpenes / administration & dosage*
  • Double-Blind Method
  • Euphorbia
  • Gels
  • Humans
  • Keratosis, Actinic / drug therapy*
  • Middle Aged
  • Pharmaceutical Vehicles
  • Plant Extracts / administration & dosage
  • Treatment Outcome


  • 3-ingenyl angelate
  • Diterpenes
  • Gels
  • Pharmaceutical Vehicles
  • Plant Extracts