Northwest Bio suspends patient screening in brain cancer trial

Northwest Biotherapeutics CEO Linda Powers sits in her company offices in Bethesda, Maryland, February 22, 2014. REUTERS/Jonathan Ernst (Reuters)

By Ransdell Pierson (Reuters) - The chief executive officer of biotechnology company Northwest Biotherapeutics Inc said on Friday the company has temporarily stopped screening new patients for the late-stage trial of its experimental brain cancer drug. CEO Linda Powers said in a telephone interview the company had halted the screening process just months before it had planned to complete patient recruitment for the seven-year-old study of the drug, DCVax-L. The company said in a statement later on Friday that the trial is ongoing and enrolled patients are continuing to be treated, but that screening had been "temporarily suspended while the company submits certain information from the trial for regulatory review." It said over 300 patients have been recruited for the study, which has a total anticipated enrollment of 348 patients. Screening is the process by which a company ensures that an individual seeking to enter a clinical trial meets eligibility requirements, such as age and not having had another cancer for the last five years. The study, among patients with newly diagnosed brain cancer, is being conducted in Germany, the United Kingdom, the United States and Canada. Northwest Biotherapeutics said some social media comments have noted that the European trial database says there has been a "temporary halt" of the trial in Germany, but said that referred only to the temporary suspension of new screening. "The key question is whether patients are able to continue treatment in their trial," Powers said. "And the answer is yes." The company said it anticipates submitting the trial information for regulatory review within the next couple of weeks. But the news unnerved many investors on Friday, with the company's shares falling as much as 11 percent on earlier reports the trial itself had been temporarily halted. Shares closed down 21.6 percent at $6.96 on Nasdaq. The company has previously said that if it were to complete recruitment of patients for the study by the end of this year, that it hopes to complete the DCVax-L study in 2016. Patients taking DCVax-L in far smaller informal trials, along with standard care, lived 2.5 times as long as typically seen with patients taking standard treatment alone. But skeptics have questioned whether the favorable results can be replicated in the larger ongoing study and some have accused the company of over-promoting limited favorable data. DCVax-L is among an emerging new crop of immuno-oncology drugs that coax the body's immune system to track down and kill cancer cells. It harnesses dendritic cells, or master cells of the immune system, that give directions to other immune cells including t-cells and b-cells, which make antibodies. The treatment is made by isolating a patient's immature dendritic cells from blood and combining them in a laboratory dish with dozens of antigens, or proteins, from brain tumor tissue of the patient obtained in surgery. The mixture is then purified and injected back into the patient. (Reporting by Ransdell Pierson in New York; Additional reporting by Deena Beasley in Los Angeles; Editing by Bernard Orr and James Dalgleish)