Treatment of skin papillomas with topical alpha-lactalbumin-oleic acid

N Engl J Med. 2004 Jun 24;350(26):2663-72. doi: 10.1056/NEJMoa032454.


Background: We studied the effect on skin papillomas of topical application of a complex of alpha-lactalbumin and oleic acid (often referred to as human alpha-lactalbumin made lethal to tumor cells [HAMLET]) to establish proof of the principle that alpha-lactalbumin-oleic acid kills transformed cells but not healthy, differentiated cells.

Methods: Forty patients with cutaneous papillomas that were resistant to conventional treatment were enrolled in a randomized, placebo-controlled, double-blind study, in which alpha-lactalbumin-oleic acid or saline placebo was applied daily for three weeks and the change in the volume of each lesion was recorded. After this first phase of the study, 34 patients participated in the second phase, an open-label trial of a three-week course of alpha-lactalbumin-oleic acid. Approximately two years after the end of the open-label phase of the study, 38 of the original 40 patients were examined, and long-term follow-up data were obtained.

Results: In the first phase of the study, the lesion volume was reduced by 75 percent or more in all 20 patients in the alpha-lactalbumin-oleic acid group, and in 88 of 92 papillomas; in the placebo group, a similar effect was evident in only 3 of 20 patients (15 of 74 papillomas) (P<0.001). After the patients in the initial placebo group had been treated with alpha-lactalbumin-oleic acid in the second phase of the study, a median reduction of 82 percent in lesion volume was observed. At follow-up two years after the end of the second phase, all lesions had completely resolved in 83 percent of the patients treated with alpha-lactalbumin-oleic acid, and the time to resolution was shorter in the group originally assigned to receive alpha-lactalbumin-oleic acid than among patients originally in the placebo group (2.4 vs. 9.9 months; P<0.01). No adverse reactions were reported, and there was no difference in the outcomes of treatment between immunocompetent and immunosuppressed patients.

Conclusions: Treatment with topical alpha-lactalbumin-oleic acid has a beneficial and lasting effect on skin papillomas.

Publication types

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

MeSH terms

  • Administration, Cutaneous
  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Double-Blind Method
  • Female
  • Follow-Up Studies
  • Humans
  • Immunocompromised Host
  • Lactalbumin / isolation & purification
  • Lactalbumin / therapeutic use*
  • Male
  • Middle Aged
  • Milk, Human / chemistry
  • Oleic Acid / therapeutic use*
  • Warts / drug therapy*
  • Warts / pathology


  • Oleic Acid
  • Lactalbumin