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LONDON, June 17 (Reuters) - British drug developer Scancell has suspended dosing in a cancer clinical trial becauseof quality problems with an immunotherapy treatment, wiping morethan a quarter off the value of its shares on Friday.
The company said tests showed that a stored supply of themedicine SCIB1, which is being assessed for melanoma, haddeteriorated and was "no longer within the originalspecification".
Scancell is planning to make a fresh batch of SCIB1 butthere will be a delay of approximately nine to 12 months beforethe 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 theclinical study out of 35 who have received treatment.
The trial was originally started in 2010 but it has beenextended on several occasions. As a result, some of the drugsupply has now been stored for more than seven years. (Reporting by Ben Hirschler; Editing by Alexander Smith andJason Neely)
Scancell Holdings (SCLP)