Following on from the single dose trial we commenced with a multi-dose trial in 2012.
The trial was based at the the Royal Brompton Hospital in London and at the Western General Hospital and Royal Hospital for Sick Children in Edinburgh. We recruited ~130 people with CF (aged 12 years and above) into the trial.
The trial was a blinded, placebo-controlled study, meaning that each participant had a 50:50 chance of receiving gene therapy or 'dummy' treatment, with neither participants nor investigators knowing which.
Participants received a dose of gene therapy or 'dummy' treatment via a nebuliser once a month for 12 months.
The gene therapy will consist of the healthy CFTR gene which will be carried into the cells of the airways by a liposome (a fatty substance) called GL67A. This is the same liposome which we used in clinical trials in the 1990s and we therefore have results on its safety and efficacy. The product however, has been substantially improved and has recently been used in the single dose clinical trial to ensure its safety and to see how long each dose lasts.
You can learn more about our gene therapy product GL67A/pGM169 in this section of our website.
Patients on the multi-dose trial will undergo the following tests:
A small sub-group of participants also received an additional dose by nasal spray. These patients underwent nasal potential difference analysis and nasal brushings to look for molecular evidence of gene transfer.
We also looked for evidence of this in the lower airways of a subgroup of patients who will be asked to undergo two bronchoscopies.
Results are expected to be announced in the first quarter of 2015