Scancell slumps as drug problem disrupts melanoma trial

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LONDON, June 17 (Reuters) - British drug developer Scancell has suspended dosing in a cancer clinical trial because of quality problems with an immunotherapy treatment, wiping more than a quarter off the value of its shares on Friday.

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 Neely)