Milazzo S, et al. Laetrile treatment for cancer. Cochrane Database Syst Rev. 2011 Nov 9;11:CD005476.
This review was conducted to assess the anticancer and possible adverse effects of laetrile and amygdalin. The databases CENTRAL (2011, Issue 1); MEDLINE (1951–2011); EMBASE (1980–2011); AMED; Scirus; CancerLit; CINAHL (all from 1982–2011); CAMbase (1998–2011); the MetaRegister; and the National Research Register were searched for the review. Sixty-nine studies were evaluated, but none met the inclusion criteria. Researchers concluded that the claims of beneficial effects made for laetrile or amygdalin are currently not supported by any clinical data. Further, there is a great risk of serious side effects from cyanide poisoning, especially following oral consumption of laetrile or amygdalin.
Moertel CG, et al. A clinical trial of amygdalin (laetrile) in the treatment of human cancer. New Eng J Med 1982;306:201-6.
A prospective, open-label evaluation of amygdalin plus “metabolic therapy” was conducted in 178 patients with various cancers. All patients were in generally good health and one-third had not received any prior treatment. Patients received 21 days of intravenous amygdalin 4.5 g/m2 followed by 500 mg amygdalin tablets three times daily. In addition, patients were placed on a metabolic therapy consisting of vitamins (A, C, E, B complex), minerals, and pancreatic enzyme supplementation. A diet restricting eggs, dairy, meats, and caffeinated and alcoholic beverages was also encouraged. Primary outcomes measured were tumor response and survival. Of 175 evaluable patients, there was one partial response, 79% had disease progression after 2 months, and 91% progressed by 3 months. Median survival based on all patients was 4.8 months from therapy initiation. Many adverse effects noted were related to cyanide toxicity, including headache, nausea, vomiting, dizziness, and mental obtundation. The results suggest that amygdalin is ineffective in the treatment of cancer.