BOSTON, Jan. 11, 2016 /PRNewswire/ -- GW Pharmaceuticals plc ("GW Pharma" or the "Company") (NASDAQ:  GWPH) has dropped precipitously in early trading.  It was down as much as 10% after a Sunday Times report referred to weakness in the Company's accounting practices.  GW Pharma had stated in its annual report that it "had a material weakness in our internal control over financial reporting for the year ended September 30, 2015."

The Company further stated that its:

management identified a material weakness and concluded that our internal controls over financial reporting were not effective as ofSeptember 30, 2015. …  Our management determined that our control over the completeness and valuation of clinical trial accruals is not effective. Specifically, management does not have sufficiently precise controls to evaluate the completeness and accuracy of the calculation of clinical trial accruals due to the incorrect allocation of expenditure to clinical studies. Additionally, we have not established a sufficiently precise...