Peanut induced anaphylaxis (believed to be an IgE mediated condition) may result in death. Mortality in this increasingly common illness is usually associated with accidental ingestion of the equivalent of one to two peanuts. This multicentred, double blind, randomised, controlled study investigated 84 patients with a known immediate hypersensitivity response to peanuts. Patients were allocated to receive placebo or a series of weekly doses of TNX-901 (150 mg, 300 mg, or 450 mg) over the 4 week study period. TNX-901 is a monoclonal antibody directed against IgE. Increasing doses of this antibody provided statistically significant protection (p<0.01) against oral peanut challenge. At the highest dose (450 mg) protection was provided against the equivalent of nine peanuts (enough to guard against most cases of unintentional exposure) 4 weeks after the last administration. The antibody was well tolerated.

Until now the mainstay of treatment of peanut induced anaphylaxis has been self-administered adrenaline, but patients may forget to carry this. TNX-901 may prove to be a beneficial alternative therapeutic agent for this condition. However, the trial was performed over 4 weeks only and further long term studies are required.