Many hundreds of people have shown interest in our planned ASCOT
trial, comparing use of autologous stromal (mesenchymal) stem cells with
chondrocytes in repairing cartilage in the knee. This is an update which
we hope is of help.
Many different types of cell therapy are now being used for a range of problems
such as skin loss, eye problems etc. A new form of license is available
for the facilities that grow these cells, and also new regulations govern
the running of clinical trials such as ASCOT. We have now received ethics
committee support for the trial design. Obtaining the new type of cell
production license is the next step before obtaining support from the
governing body, MHRA, for the ASCOT clinical trial.
The Oscell team is also busy on other development work. Over
the 14 years we have provided this service the outcome seems to steadily
improve, and complications reduce. There is however in all studies worldwide,
and in knee joint replacement in younger patients, a limit to the ability
to get everyone to improve. The figure is around 80% to 90% success at
5 years. One of our aims is to find how to avoid these failures.
Finding how to select suitable patients for autologous chondrocyte implantation
(ACI), to identify the important variables in how the surgery is done, and
how rehabilitation proceeds, are all important to improving outcome. This
will be important in how we will run the ASCOT trial. If there is a lot
of variation in outcome then it is difficult to pick up small differences
in a comparative trial.
We have always selected patients who have failed to respond to other treatments.
Unfortunately this in itself is a factor that may reduce against
success of autologous chondrocyte implantation. The duration
of symptoms correlates directly with failure, as found by
the Tigenix study in Belgium. What is it about the duration
of symptoms that makes treatment more difficult? Smoking appears
to reduce the chance of a good outcome from micro fracture.
Why is this? These are the sorts of questions that need answers.
Of note, there are an increasing number
of studies that find ACI better than other treatments such
as micro fracture or mosaicplasty in treating chondral defects.
These are summarised by the recent publication in the journal
We have treated 400 patients now with
ACI and many are joining a study called REACT. This study
is ethically approved and examines the different variables
in their treatment, the relative importance of the surgical
techniques, and differences in rehabilitation post-operatively,
and the long term cost-effectiveness. Identifying the indicators
that predict both a good and a bad outcome from ACI is now
well under way and the results will help in running the trial,
In the meantime we are also busy treating
patients with autologous chondrocyte implantation who have
failed to respond to other treatments from across the country,
under the guidelines set by NICE.