The authors of a paper, published three-and-a-half years ago in Nature Medicine, that claimed that patients with terminal kidney cancer had been successfully treated with individualized cancer vaccines, have finally retracted their work.

Scientists in Germany, where the clinical studies were carried out, say they are relieved that the long-drawn-out affair is closed. But they claim that the delay in correcting the record has sapped researchers' morale.

An investigation committee at the University of Göttingen reported last November that the paper “failed to meet the requirements of good scientific practice”. It found the lead author, Alexander Kugler, guilty of gross negligence, but cleared the other 14 co-authors of scientific misconduct (see Nature 420, 258; 200210.1038/420258a).

The contested vaccine trials, sponsored by the Bad Homburg-based healthcare company Fresenius, were suspended more than a year earlier following allegations of irregularities in clinical practice, and the university had been accused of being slow to complete its investigation (see Nature 417, 6; 200210.1038/417006b).

The retraction appears in this month's issue of Nature Medicine, with an editorial explaining why it took the journal a further ten months from the committee's ruling to persuade the reluctant authors to retract and to agree a form of words (Nature Med. 9, 1221; 2003). “We wanted the authors themselves to retract rather than issuing a retraction from the journal,” says editor Beatrice Renault. “It is more meaningful if authors take the responsibility, and it has more power within the scientific community.”

One of the authors, Rolf-Hermann Ringert of the University of Göttingen, says that despite errors in the publication — which include inaccuracies in the primary data and inclusion of patients who did not fulfil the requirements of the trial — he tried for a long time to persuade the journal to publish a list of detailed corrections, rather than a retraction. He says that he still stands by the authors' central claim to have proven the principle that this type of 'fusion' cancer vaccine is effective.

Vaccines of this sort fuse patients' tumour cells with healthy dendritic cells, which present antigens to the immune system in a way that signals that the antigens are foreign and should be destroyed. When the patients are injected with the fused cells, their immune system should be alerted to destroy the cancer cells that they had previously tolerated.

Others working on fusion vaccines say that the Kugler case has had a negative effect on funding in this area and has made it harder to publish results. But groups in the United States and Japan have now reported anticancer activity of modified fusion vaccines in early-phase trials in breast cancer and in glioma, a type of brain tumour. Fresenius is planning a further trial on kidney cancers at the University of Göttingen, applying optimized fusion technologies, a spokesman for the company says.

Ulf Rapp, a cell biologist at the University of Würzburg and head of a task force that investigated an earlier, unrelated scientific misconduct case, says that the retraction “is the right outcome, but it could have come faster. Journals owe it to their image to take matters into their own hands when an investigation exposes errors and authors are hard to track down, or reluctant to retract.”