The latest study was designed to confirm the most effective dose of NTCELL, define any placebo component of the response and further identify the initial target Parkinson's disease patient subgroup.
The biotech firm's Phase IIb clinical trial was completed in April and it had been waiting for the results to be unblinded,
There were three groups of six patients and two patients from each group had sham surgery with no NTCELL implanted, to act as a control.
The remaining patients received different numbers of microcapsules of NTCELL on each side of the brain.
While no product or procedure adverse events occurred and there is no evidence of xenogeneic infection in patients and their partners "we are disappointed that the efficacy primary endpoint has not been met," said Taylor.
Principal investigator Barry Snow at Auckland City Hospital said the next step is to analyse the data in depth and continue to monitor patients in accord with the study extension protocol, particularly for the efficacy movements at longer time points.
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