NZ Parkinson's trial on hold - experts
respond
An Auckland biotech company is
putting its trial of an experimental Parkinson's disease
treatment on hold following the withdrawal of previous
animal research.
Living Cell Technologies (LCT) has suspended patient recruitment for a clinical trial testing thexenotransplantation of specially encapsulated pig-derived cells (NTCELL) as a treatment for Parkinson's disease.
Earlier research from the company had shown the implanted cells were effective in treating animal models of Parkinson's disease in rats and monkeys. However, following the discovery that the original data from rat study was incomplete, LCT has retracted the study, published in the journalRegenerative Medicine.
"The publication is being withdrawn following an internal quality assurance audit which showed that the source data for the study held on file at LCT are incomplete and therefore the efficacy conclusions in the publication cannot be confirmed," the company said in a press release.
In the light of the retraction LCT, which is a listed company on the Australian stock exchange, announced its early stage human trial taking place at Auckland hospital would not be recruiting further patients. One patient is already taking part in the trial and will continue treatment as planned.
The company said this was a "precautionary measure" to "allow the company to work with the New Zealand medicines regulator (Medsafe) and the data safety monitoring board (DSMB) to fully understand the impact of the withdrawal of the rat efficacy data on the Phase I clinical trial."
A full record of the planned
NTCELL trial can be found on the US clinical
trials registry,
clinicaltrials.gov. The Science
Media Centre has rounded up reaction from
experts:
Professor Gareth Jones,
Bioethics Centre, University of Otago,
comments:
"Transplantation of neural grafts into
patients with Parkinson's Disease has had a long and
unsatisfactory history, even though it was originally based
on well conducted and encouraging studies in animals. In
light of this it behoves any new procedures to be
exceedingly careful and rigorous about the pre-clinical work
undertaken on animal models. This is essential since the
transplantation is into patients with a debilitating
neurological disease, and who expect to benefit from these
procedures, and are not simply treated as experimental
subjects.
"In this instance the procedures are particularly complex, involving as they do xenotransplantation (from pigs), and therefore if the procedures are to be ethical there has to be no doubt that the porcine tissue transplants work in the first place in animal models. The slightest doubt about this should automatically exclude any use of the porcine tissue in human subjects. If additional caution is not exercised in a case like this one, its ethical character has to be questioned."
Dr George Slim, chief executive
officer of biotech industry group NZBio,
comments:
"The most important issue this
particular case highlights is the complete response of LCT.
As soon as the issue was raised in an internal audit the
company has taken a precautionary approach; suspending the
clinical trial, having the paper retracted and more
importantly taking care of the patient already enrolled in
the trial. They have been prepared to communicate with
investors and the media. I think this professional response
to something that did not in fact raise safety issues is a
lesson to companies world-wide, not just in New
Zealand.
"Not knowing the specifics of what caused the issues with the data in this case, there are a couple of general points. There is always pressure to get data out as fast as possible in research, commercial or academic - large organisation or small. Similarly there are always resource constraints. The funding is tight for academic researchers reliant on grants as it is in a biotech company using investors' money to bring a product to market. Even in Big-Pharma research funding is being squeezed.
"What does change as projects move from discovery research to developing commercial products is the need to introduce auditable systems and processes. These have to be in place to ensure consistency and to satisfy regulators, especially in the biomedical area. The discipline of meeting regulatory requirements and doing everything in exactly the same way every time can be difficult for researchers used to constantly searching for new ways to do things. It is hard for a New Zealand start-up to get staff with regulatory experience but the pool is growing as we have more successful companies involved in late-stage clinical trials and with products on the market.
"I think it is a sign of the sector's maturity that I used to hear a lot about the need to educate New Zealand researchers in intellectual property management and now I hear calls for people with regulatory training. I take that as a sign that the NZ biomedical sector is getting better at the discovery stage and moving out into development."
ENDS