The company said tests showed that a stored supply of the medicine
SCIB1, which is being assessed for melanoma, had deteriorated and
was "no longer within the original specification".
Scancell is planning to make a fresh batch of SCIB1 but there will
be a delay of approximately nine to 12 months before the new
material is available for use.
Scancell's shares slumped 27 percent to six-month lows, their worst
day in nearly three years.
The suspension of dosing affects eight patients in the clinical
study out of 35 who have received treatment.
The trial was originally started in 2010 but it has been extended on
several occasions. As a result, some of the drug supply has now been
stored for more than seven years.
(Reporting by Ben Hirschler; Editing by Alexander Smith and Jason
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