industry biomedicine successor valeant pharmaceuticals defunct 2015 headquarters russell investments center seattle washington us products provenge services provenge number of employees 1497 website www.dendreon.com dendreon was a seattle biotechnology company . its lead product provenge known generically as sipuleucel t was an immunotherapy for prostate cancer . it consists of a mixture of the patient s own blood cells autologous with dendritic cells thought to be the most important that have been incubated with the dendreon pap gm csf fusion protein . phase iii clinical trial results demonstrating a survival benefit for prostate cancer patients receiving the drug were presented at the aua meeting on april 28 2009 . 1 after going through the approval process provenge was given full approval by the fda on april 29 2010 . 2 dendreon s stock value fell 66 % on august 4 2011 after abandoning its forecast for its debut drug provenge . 3 in november 2014 dendreon filed for chapter 11 bankruptcy protection and shortly afterwards announced that it had reached agreements on the terms of a financial restructuring with certain bond holders . 4 on february 20 2015 valeant pharmaceuticals received approval to purchase all dendreon assets . contents 1 technology overview and pipeline 1.1 antigen delivery cassette and antigen presenting cells 1.2 antigen selection 1.3 nuvelo and patents acquired from corvas 2 early history 3 provenge 4 dendreonites 5 list of us patents and patent applications 6 references 7 external links technology overview and pipeline edit this section needs additional citations for verification . please help improve this article by adding citations to reliable sources . unsourced material may be challenged and removed . may 2010 learn how and when to remove this template message antigen delivery cassette and antigen presenting cells edit dendreon s name derives from the dendritic cell which forms a major component of the company s product candidates that use the dendreon cassette technology to insert a disease specific target protein into a general platform . their lead product provenge is an example of their rationally designed therapeutic process intended to break immune tolerance to certain disease specific proteins . it is hypothesized that receptor mediated uptake of antigen by dendritic cells occurs when they are exposed to the dendreon fusion protein which links the disease specific protein to a recognition protein . this approach is in contrast to other dendritic cell vaccines that use methods such as electroporation to get the dc s to present antigen related epitopes . in the case of provenge this disease related protein is prostatic acid phosphatase and the signalling component is gm csf . antigen selection edit dendreon believes its process can be optimized and generalized to other diseases by exchanging the pap component of provenge with better targets specific to different diseased cells . 5 antigen selection is a significant issue with cancer vaccines in general . presumably therapeutic effect can be obtained by provoking a selective response against the diseased cells only . dendreon has explored approaches to obtaining tumour specific antigen targets under the theory that the immune system may be able to mount a more effective response than is otherwise possible against tumor associated antigens . unaltered human pap is expressed by normal prostate cells but recent discoveries suggest that cancer cells produce many more unique targets as well as proteins that are more highly expressed than in normal tissue . 6 it has also been recently discovered that other enzymes expressed in nerves are identical to pap 7 8 and there is ongoing work to examine post translational modifications to pap and its correlation to disease state by dendreon collaborators . 9 pap also appears to be expressed in breast cysts . 10 prior work in this area has also included that of a. sette at epimmune and the altered peptide ligand approach typified by neurocrine biotech s failed ms drug . nuvelo and patents acquired from corvas edit dendreon acquired the nematode anticoagulant nuvelo . 11 selected corvas patents include technologies for peptide analog synthesis and drugs that target coagulation and immune processes . early history edit dendreon was founded in 1992 by edgar engleman and samuel strober based on the research performed in their laboratories at the stanford university school of medicine . drs. engleman and strober established the company initially named activated cell therapy in mountain view california after securing funding from health care ventures in edison new jersey . 12 after several years the company changed its name to dendreon and moved to seattle washington . provenge edit main article provenge initial clinical results for provenge in 2000 showed immune responses supporting the expected mode of action as well as a psa reduction which was thought to relate to clinical improvement . 13 in 2006 dendreon built a manufacturing facility in morris plains new jersey to accommodate production for a phase iii trial and possible 2007 drug approval by the u.s. food and drug administration fda . 14 in january 2007 the fda accepted dendreon s biologic license application bla filing for provenge . 15 on march 29 2007 the fda office of cellular tissue and gene therapies advisory committee voted 17 0 that provenge is reasonably safe and 13 4 that the trial data showed substantial evidence that it is effective . 16 however on may 9 2007 dendreon received a letter from the fda demanding more results and information before approval . 17 on april 14 2009 dendreon announced that the results for the phase iii trial of provenge were positive saying there had been a reduction in the odds of death compared to the use of a placebo . 18 on april 28 2009 the full details of the study were released . the trial found that patients treated with provenge lived an average of 4.1 months longer than patients treated with the control autologous cells without the gm csf pap fusion protein . 19 on april 29 2010 the fda approved provenge for use in the treatment of advanced prostate cancer . on june 7 2010 the head of medicare s coverage and analysis group dr. louis jacques sent three colleagues an email telling them that they should be sure not to leak the fact that his group was considering a cap on medicare coverage of this treatment . news of that caution itself did inevitably leak and the price of dendreon s stock fell 10 % later that day . dendreonites edit some journalists have referred to provenge supporters as dendreonites and the name is in routine usage in colloquial forums . 20 concerns for personal safety were raised among some doctors who were thought responsible for the delay of provenge approval . 21 dendreonites have questioned these doctors objectivity ; as dr. scher was the lead clinical trial investigator for a rival prostate cancer drug from the biotech company novacea . 20 their concerns motivated organized protests at the fda and american society of clinical oncology asco meeting by various patient and investor advocacy groups which also filed a lawsuit alleging that the fda s decision was influenced by conflicts of interest . 22 list of us patents and patent applications edit this section may be too technical for most readers to understand . please help improve this section to make it understandable to non experts without removing the technical details . the talk page may contain suggestions . may 2010 learn how and when to remove this template message u.s. patent 7 414 108 august 19 2008 laus ; reiner ruegg ; curtis l. shapero ; michael h. yang ; demao composition and method for producing an immune response against tumor related antigens . disclosed are a novel prostatic acid phosphatase and corresponding coding region derived from mouse . also disclosed is a method of producing an immune response against an autologous polypeptide tumor antigen by immunizing a subject with a xenogeneic polypeptide antigen either alone as part of a viral antigen construct or as part of a pulsed dendritic cell preparation . u.s. patent 6 210 662 july 9 2002 laus ; reiner ruegg ; curtis landon wu ; hongyu immunostimulatory composition . disclosed are therapeutic compositions and methods for inducing cytotoxic t cell responses in vitro and in vivo . the therapeutic compositions consist of antigen presenting cells activated by contact with a polypeptide complex constructed by joining together a dendritic cell binding protein and a polypeptide antigen . also disclosed are expression vectors and systems for producing the polypeptide complexes . u.s. patent 6 194 152 april 3 2001 laus ; reiner shapero ; michael h. tsavaler ; larisa prostate tumor polynucleotide compositions and methods of detection thereof . the present invention is directed to novel polynucleotides and the polypeptides encoded by them each of which are specific to human prostate tumor cells . the present invention further provides chimeric polypeptide molecules comprising the polypeptides of the present invention fused to heterologous polypeptide sequences and antibodies which bind to the polypeptides of the present invention . also provided herein are methods for producing the polypeptides of the present invention as are detection assays that detect the presence of tumor cells in tissue or bodily fluid samples and methods for identifying novel compositions which modulate the activity of prostate tumor antigens and the use of such compositions in diagnosis and treatment of disease . u.s. patent 6 080 409 february 27 2001 laus ; reiner ruegg ; curtis landon wu ; hongyu immunostimulatory method . disclosed are therapeutic compositions and methods for inducing cytotoxic t cell responses in vitro and in vivo . the therapeutic compositions consist of antigen presenting cells activated by contact with a polypeptide complex constructed by joining together a dendritic cell binding protein and a polypeptide antigen . also disclosed are expression vectors and systems for producing the polypeptide complexes . u.s. patent 5 976 546 december 7 1999 laus ; reiner ruegg ; curtis landon wu ; hongyu immunostimulatory compositions . disclosed are therapeutic compositions and methods for inducing cytotoxic t cell responses in vitro and in vivo . the therapeutic compositions consist of antigen presenting cells activated by contact with a polypeptide complex constructed by joining together a dendritic cell binding protein and a polypeptide antigen . also disclosed are expression vectors and systems for producing the polypeptide complexes . references edit aua impact trial presentation summary pdf . update 3 u.s. fda oks dendreon s prostate cancer vaccine . reuters . 29 april 2010 . retrieved 2010 05 02 . berkrot bill 4 august 2011 . dendreon plunges as provenge prospects wither . reuters . retrieved 2011 08 04 . dendreon files for chapter 11 bankruptcy press release . reuters . 10 november 2014 . bbc global news . interview by julian king and otis brawley . globalnews 0400 gmt . bbc uk podcast . london . 30 april 2010 . podcast . rickman ds pflueger d moss b et al. april 2009 . slc45a3 elk4 is a novel and frequent erythroblast transformation specific fusion transcript in prostate cancer . cancer research . 69 7 2734 8 . doi 10.1158 0008 5472 . can 08 4926 . pmid 19293179 . zylka mj sowa na taylor blake b et al. october 2008 . prostatic acid phosphatase is an ectonucleotidase and suppresses pain by generating adenosine . neuron . 60 1 111 22 . doi 10.1016 j.neuron .2008.08.024 . pmc 2629077 . pmid 18940592 . zimmermann h march 2009 . prostatic acid phosphatase a neglected ectonucleotidase . purinergic signalling . 5 3 273 5 . doi 10.1007 s11302 009 9157 z. pmc 2717315 . pmid 19322680 . white ky rodemich l nyalwidhe jo et al. february 2009 . glycomic characterization of prostate specific antigen and prostatic acid phosphatase in prostate cancer and benign disease seminal plasma fluids . journal of proteome research . 8 2 620 30 . doi 10.1021 pr8007545 . pmc 2651839 . pmid 19128049 . erbas h erten o irfanoglu me december