April 11, 2014 – Dendreon Corporation (NASDAQ:DNDN) today announced the presentation of preliminary data from a long-term analysis of the Phase II STAND study demonstrating that tumor-specific T-cell responses appear to be enhanced and sustained when PROVENGE® (sipuleucel-T) is given after androgen deprivation therapy (ADT) in patients with biochemically-recurrent prostate cancer (BRPC) at high risk for metastases. These data will be presented at the 29th Annual European Association of Urology (EAU) Congress taking place from April 11-15, 2014 in Stockholm, Sweden.1

“We are pleased with the preliminary STAND data, which show the continued potential for sequencing PROVENGE with other treatments and the impact that immunotherapy has on immune responses in advanced prostate cancer patients,” said Andrew S. Sandler, M.D., executive vice president and chief medical officer at Dendreon. “The presentation of these data at EAU highlights Dendreon’s commitment to expanding awareness and understanding of immunotherapy and PROVENGE in Europe as we prepare to make PROVENGE available to advanced prostate cancer patients beyond the United States.”

ADT is a standard treatment option for men with BRPC after failure of local therapy. The STAND study is a randomized, Phase II trial that consisted of two patient study groups, one completing PROVENGE two weeks before ADT and the second receiving PROVENGE three months after the start of ADT. Preliminary results suggest enhanced cellular immune responses when PROVENGE was given after ADT, and these responses were persistent for at least 12 months and robust in both patient groups.

“The STAND study results are encouraging as they provide additional evidence on how sipuleucel-T can be sequenced with other treatments which will assist clinician decision-making upon whether immune responses correlate with certain clinical parameters, such as prostate specific antigen (PSA) recurrence,” said Neal Shore, M.D., medical director at the Carolina Urologic Research Center.

PROVENGE is approved in all 28 countries of the European Union (EU) as well as Norway, Iceland and Liechtenstein for the treatment of asymptomatic or minimally symptomatic metastatic (non-visceral) castrate resistant prostate cancer in male adults in whom chemotherapy is not yet clinically indicated. Dendreon plans to make PROVENGE commercially available in Europe, beginning with Germany and the United Kingdom, through Centers of Excellence.

Important Safety Information for PROVENGE

PROVENGE is intended solely for autologous use and should under no circumstances be administered to other patients.

The safety evaluation of PROVENGE was based on data from 601 prostate cancer patients in four randomized clinical trials and post-marketing surveillance.

PROVENGE should be delayed in patients with active systemic infection until resolution and used with caution in patients with a history of embolic and thrombotic events, including cerebrovascular disease and cardiovascular disorders.

Serious adverse reactions reported include acute infusion reactions (occurring within 1 day of infusion), catheter sepsis, staphylococcal bacteremia, myocardial infarction and cerebrovascular events.

The most commonly reported adverse reactions were chills, fatigue, pyrexia (fever), nausea, arthralgia (joint ache), headache, and vomiting.

About Dendreon

Dendreon Corporation is a biotechnology company whose mission is to target cancer and transform lives through the discovery, development, commercialization and manufacturing of novel therapeutics. The Company applies its expertise in antigen identification, engineering and cell processing to produce active cellular immunotherapy (ACI) product candidates designed to stimulate an immune response in a variety of tumor types. Dendreon's first product, PROVENGE® (sipuleucel-T), was approved by the U.S. Food and Drug Administration (FDA) in April 2010. Dendreon is exploring the application of additional ACI product candidates and small molecules for the potential treatment of a variety of cancers. The Company is headquartered in Seattle, Washington, and is traded on the NASDAQ Global Market under the symbol DNDN. For more information about the Company and its programs, visit http://www.dendreon.com/.

Statements in this press release that are not strictly historical in nature constitute "forward-looking statements." Such statements include, but are not limited to, statements regarding the expected benefits of the recent and prior restructurings, the timing and elements of the restructurings, the timing and form of related charges, the expected annual operating expense reductions, expectations and beliefs regarding Dendreon's financial position, profitability and Dendreon's ability to break even and achieve improved performance as a result of the restructurings, statements regarding sequencing studies, statements regarding studies to advance understanding of immunotherapy and the treatment of advanced prostate cancer, statements regarding biomarkers, expectations about automation or the early detection study, expectations about advancing our pipeline, expectations regarding reductions of cost of goods sold, expectations regarding reimbursement approvals of PROVENGE® in Europe or Dendreon's ability to launch and commercialize PROVENGE in Europe, expectations regarding the presentation of clinical data, developments affecting Dendreon's U.S. and global business and prospects, beliefs and expectations regarding potential revenue and earnings from product sales, including beliefs regarding Dendreon's ability to grow sales, expectations regarding market size, target market, and market opportunity, beliefs regarding the impact of our direct to consumer advertising, expectations with respect to our sales force execution and effectiveness, progress generally on commercialization efforts for PROVENGE, and expectations about clinical trial enrollments. Such forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause Dendreon's actual results to be materially different from historical results or from any results expressed or implied by such forward-looking statements. These factors include, but are not limited to, our inability to achieve and sustain commercial success for PROVENGE; the identification of efficacy, safety or other issues with PROVENGE; a slower than anticipated adoption by treating physicians of PROVENGE for the treatment of patients with advanced prostate cancer for a variety of reasons, including competing therapies, instability in our sales force, the risk that we cannot replace vacant sales positions on a prompt basis, perceived difficulties in the treatment process, delays in obtaining reimbursement or for other reasons; any promotional limitations imposed by the FDA or the EU on our ability to commercialize and market PROVENGE; unexpected difficulties and costs associated with the rapid expansion of our commercial operations to support the commercial launch of PROVENGE; the impact of competing therapies on sales of PROVENGE, the failure to achieve reimbursement approvals in Europe, manufacturing or quality difficulties, the dilution or other effects resulting from capital raising or debt restructuring transactions, disruptions or delays and other factors discussed in the "Risk Factors" section of Dendreon's Annual Report on Form 10-K for the year ended December 31, 2013. All forward-looking statements are qualified in their entirety by this cautionary statement. Dendreon is providing this information as of the date of this press release and does not undertake any obligation to update any forward-looking statements contained in this release as a result of new information, future events or otherwise.

1 Results of this analysis from the randomized, open-label Phase II study will be presented as follows: A randomized phase II study evaluating the optimal sequencing of sipuleucel-T and androgen deprivation therapy (ADT) in biochemically-recurrent prostate cancer (BRPC): Immune results with a focus on humoral responses. April 14, 14:00 – 15:30 CET, Androgen deprivation therapy, still work to be done (Poster Session 79, Room A8)