"More action should be taken, including potentially legal action" to curb this worrying trend and "protect the integrity of research and the trust of the public in medical research," said authors of the article, Trudo Lemmens, Associate Professor of Law and Medicine, and Paul Miller, a Ph.D. candidate in philosophy, both at the University of Toronto, Canada.
More pharmaceutical clinical trials are being undertaken than ever before, however, it is becoming increasingly difficult to recruit suitable study subjects, particularly in major therapeutic areas such as cardiovascular and gastrointestinal diseases.
Patient recruitment consumes thirty per cent of clinical trial time - more time than any other clinical trial activity - and almost half of all trial delays result from patient recruitment problems.
These delays in are costing drug companies over half a million dollars for specialty products and more than $8m (€6.7m) for blockbuster brands in lost sales and are also causing the cost of running clinical trials to skyrocket, according to market intelligence firm Cutting Edge Information.
As a result, competition between rival pharma firms is now fierce and in a desperate bid to fill clinical trial quotas, more and more clinicians are being paid recruitment incentives by clinical research organisations (CROs) and trial sponsors.
In some instances, the fees paid to individual investigators may be as high as $5,000 per patient, the authors state in the article.
Concerns over the practice are numerous and include the possibility of clinicians being influenced or driven to act fraudulently by the incentives, as well as inappropriately enrolling patients, against the best interest of both the patient and the trial outcome.
The authors point to the example of a hospital in Albany, New York, where an investigation by the Food and Drug Administration (FDA) uncovered altered patients' medical records in five clinical trials, in order to enrol patients who didn't meet the required eligibility criteria.
The hospital was receiving a fee of $5,000 for each patient enrolled, and some individual investigators also received undisclosed incentives, said the article.
Another recent example is in the case of Ketek, an antibiotic found to have links to liver failure that was allegedly approved on the back of fraudulent clinical evidence.
Doctors were paid $100 for each patient they signed up, another $150 when they submitted study results, and a final $150 after all questions were resolved.
However, the investigator at the highest enrolling site was found to be attracting patients by advertising weight-control treatments and enrolling them when the clinic was closed, and patient consent forms had date modifications and signature inconsistencies.
Both these cases led to criminal prosecution and prison terms for those investigators who were found guilty.
Although the practice of finder's fees has been condemned by some academic institutions and professional groups, such as the American Medical Association's Council on Ethical and Judicial Affairs, and there are also Federal laws in place that could be used to prosecute investigators who act inappropriately, this is not enough to prevent the practice, and more should be done, the authors of the article state.
"The problems raised by finder's fees ought to be addressed as part of a broader institutional and regulatory reform effort designed to address weaknesses in research governance," said the authors.
"In the meantime, regulatory agencies and professional organisations such as the FDA and the HHS`s Office for Human Research Protections should take action by looking more carefully at recruitment centres."
The >article can be read in the August issue of PLoS Medicine.