Drug company halts trial of colon cancer drug

The Pan European Trial in Adjuvant Colon Cancer-1 (PETACC-1) trial has been halted after preliminary results showed a high death rate from AstraZeneca's new drug, raltitrexed.

The trial was large 530 institutions in 13 cooperative groups from 24 countries. At the time the trial was stopped, 1,838 patients were taking part and recruitment was ongoing. Early results showed that the number of drug related deaths in the raltitrexed group was double that of controls (who were taking a standard regimen of fluorouracil plus folinic acid).

AstraZeneca put the deaths down to investigators not following dosage instructions 11 of the 17 drug related deaths in the raltitrexed group had been linked with serious deviations from the trial protocol. Participants in the raltitrexed group also experienced more adverse effects from the drug (20 per cent compared to 12 per cent) and more recurrences of cancer (9 per cent compared to 2 per cent).

The fact that a commercial company funded the study and called a halt to it when its product failed to perform (and thus be commercially viable) is worrying for many observers. The interim data on the safety of raltitrexed will now never be analysed, and participants who entered the trial in hope of a remission or cure will never know the potential long term effects of the drug (Lancet, 1999; 354: 1045).