Number Of Centers Further Expected To More Than Double This Quarter

Bethesda, Maryland, May 3, 2011 — Northwest Biotherapeutics (OTC.BB:NWBO) today announced that four medical centers across the country are actively recruiting and screening to enroll additional new patients in the Company’s ongoing 240-patient randomized, double blind, placebo controlled clinical trial of DCVax® immune therapy for Glioblastoma multiforme (GBM), the most lethal type of brain cancer.

The four recruiting centers are located in New York (University of Rochester), Ohio (University Hospitals of Cleveland), Michigan (Henry Ford Health System) and Minnesota (Virginia Piper Cancer Institute at Abbott Northwestern Hospital).

Another eight medical centers, spread over multiple other states across the country, have been making preparations for additional enrollment in the ongoing GBM trial. At least four of these eight additional sites are expected to begin or resume recruiting and screening for such enrollment during this calendar quarter.

To date, 33 patients have already been enrolled in this ongoing 240-patient GBM brain cancer trial and its information arm, and have been proceeding through the treatment regimen and follow-up.

In prior clinical trials of DCVax® immune therapy for GBM brain cancer, the results were striking: the patients who received DCVax® showed a median survival of 3 years, compared with median survival of only 14.6 months with standard of care today (surgery, radiation and chemotherapy). In addition, the patients treated with DCVax® did not have their tumor recur for approximately 2 years, on average, as compared with tumor recurrence in just 7 months with standard of care today. Moreover, the patients treated with DCVax® did not experience any toxic side effects, in stark contrast to chemotherapies.

“We are pleased to have medical centers spread across the U.S. which are ramping up additional enrollment into our ongoing GBM brain cancer clinical trial,” said Dr. Alton Boynton, CEO of NWBT. “This will help patients participate in the trial without having to travel too far, and it will also help us accelerate the overall enrollment required for completion of the trial.”

About Northwest Biotherapeutics

Northwest Biotherapeutics is a biotechnology company focused on developing immunotherapy products that treat cancers more effectively than current treatments, without toxicities of the kind associated with chemotherapies, and on a cost-effective basis. The Company has a broad platform technology for dendritic cell-based vaccines. The Company’s lead clinical trial is a 240-patient Phase II trial in newly diagnosed Glioblastoma multiforme (“GBM”), the most aggressive and lethal of brain cancer. The Company also previously received clearance from the FDA for a 612-patient Phase III trial in prostate cancer, and clearance from the FDA for Phase I trials in five other cancers. The Company has also conducted a Phase I/II trial with DCVax® for recurrent metastatic ovarian cancer.

For further information about clinical sites and about the Company, please visit the Company’s web site at www.nwbio.com.

Disclaimer

Statements made in this news release that are not historical facts, including statements concerning future treatment of patients with GBM using DCVax®-Brain and future clinical trials, are forwardlooking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Words such as “expects,” “believes,” “intends,” and similar expressions are intended to identify forward-looking statements. Actual results may differ materially from those projected in any forward-looking statement. Specifically, there are a number of important factors that could cause actual results to differ materially from those anticipated, such as the Company’s ability to raise additional capital, risks related to the Company’s ability to enroll patients in its clinical trials and complete the trials on a timely basis, the uncertainty of the clinical trials process, uncertainties about the timely performance of third parties, and whether the Company’s products will demonstrate safety and efficacy. Additional information on these and other factors, including Risk Factors, which could affect the Company’s results, is included in its Securities and Exchange Commission (“SEC”) filings. Finally, there may be other factors not mentioned above or included in the Company’s SEC filings that may cause actual results to differ materially from those projected in any forward-looking statement. You should not place undue reliance on any forwardlooking statements. The Company assumes no obligation to update any forward-looking statements as a result of new information, future events or developments, except as required by securities laws.