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LONDON (Alliance News) - N4 Pharma PLC on Monday said it has become aware of a number of issues with the in vivo studies of its Nuvec delivery system.
On Tuesday last week, N4 announced in-vitro testing, which takes place outside of a living organism, showed a positive response to its Nuvec vaccine and cancer treatment delivery system.
However, during in-vivo tests, tests in living organisms, this positive response could not be replicated.
N4 Pharma has been collaborating with the University of Adelaide, in Australia, to see if Nuvec can increase the efficacy of the university's vaccine.
The company said "it has become clear that not only were there a number of variables between the studies", including the dosage. Moreover, the preparation and handling of Nuvec "may have differed materially from the original protocols".
N4 has determined the University of Queensland, where Nuvec originates and where in vivo success has been achieved, should repeat their original Nuvec studies and expand the study to include more variables, which is due to take three to four months.
All other work streams and non-essential studies that have not already begun are on hold.
N4 Chief Executive Nigel Theobald said: "In reviewing our various data sets and talking to our partners, it has become clear the most expeditious route to progressing Nuvec is to revert to source and the work of [University of Queensland].
"The team at UQ know Nuvec better than anyone and we feel confident a positive repeat study, clearly documented with respect to methodology, will greatly aid other contract research organisations in their studies."
"Whist it is a disappointing decision to put other work on hold, doing so keeps the company well funded to do our future planned work once we have a better documented handling and preparation protocol from UQ," he added.
Shares in N4 Pharma were down 0.7% at 4.32 pence on Monday afternoon and are down 18% since Tuesday last week.