Het vaccin Provenge zorgt voor lange uitsteltijd - drie keer zo lang dan zonder Provenge - van PSA stijging na eerste lijnsbehandeling.

18 september 2017: Lees ook dit artikel: https://kanker-actueel.nl/NL/immuuntherapie-met-provenge-spirutacel-t-geeft-betere-resultaten-op-overall-overleving-bij-gevorderde-prostaatkanker-als-deze-gevolgd-wordt-door-dendritische-celtherapie.html

1 mei 2010: Eindelijk na zoveel jaar is Provenge goedgekeurd door de FDA om te gebruiken als immuuntherapie - dendritische celtherapie bij hormoonresistente prostaatkankerpatienten. Zie recente berichtgeving hierover in gerelaterde artikelen.

juni 2003: Bron: Dendreon

Bijna drie keer zo lange periode voordat PSA verhoging optreedt bij prostaatkanker (wel voor patiënten met Gleasonscore onder de 7) door nog in onderzoeksfase verkerende vaccin Provenge in combinatie met het middel Bevacizumab (ook wel Avastin genoemd, een angiogeneseremmer en succesvol toegepast bij o.a. darmkanker met uitzaaiingen, ). Een interessante ontwikkeling, zeker omdat Dendreon ook een bindende verklaring heeft gekregen dat zij toestemming krijgen voor fase III studies voor Provenge. Zie ander artikel hieronder op deze pagina. We hebben geen tijd dit artikel nu te vertalen en geen geld om het te laten vertalen, maar wel in het Engels te lezen hieronder, zoals op ASCO gepresenteerd.

Nearly three-fold benefit in PSA doubling time seen post treatment

Dendreon Corporation (Nasdaq:DNDN) announced that preliminary results from a Phase 2 trial, P-16, indicate that a combination therapy of Provenge(R) and
Bevacizumab (Avastin(TM)) has demonstrated evidence of decreasing PSA doubling time in men with androgen dependent prostate cancer.
The results of the National Cancer Institute-sponsored trial from the
University of California, San Francisco (UCSF) were presented today at the
American Society of Clinical Oncology 2003 Annual Meeting by Brian Rini, M.D.,
assistant professor of medicine at the University of California San Francisco.
The Phase 2 study has enrolled 14 patients to date with androgen dependent
prostate cancer who had rising PSA levels after prior surgical or radiation
therapy, but no evidence of disease recurrence on bone or CT-scan. Patients
received treatment with Provenge at weeks 0, 2 and 4 and treatment with
Bevacizumab at weeks 0, 2 and 4 and every two weeks following until progressive
disease was noted. Patients were monitored to determine effects on PSA levels,
generation of immune responses and safety.
Of 9 patients evaluable for PSA doubling time (PSADT), median PSADT increased
nearly three fold, from 8.2 months prior to study entry to 21.4 months after
treatment with Provenge and Bevacizumab. PSA doubling time is a measure of the
rate of change of PSA over time. Changes in PSADT can only be calculated for
patients who have a rising PSA after therapy. Three patients also had PSA
decreases from baseline of 12%, 33% and 64% respectively.
"Over the past few years, PSA doubling time has gained increasing acceptance
as a study endpoint that is useful for monitoring earlier stages of prostate
cancer progression, when onset of metastatic disease is still years away," said
Jelle W. Kylstra, M.D., senior medical director at Dendreon. "In several large
epidemiological studies, shorter PSA doubling times have been associated with a
more rapid progression of cancer from a non-metastatic to a metastatic state.
The often quoted Johns Hopkins study by Pound et al. (1999) found that a PSADT
of 10 months or less is associated with a worse prognosis. The fact that these
results suggest the ability to shift patients from a poor prognostic category to
a more favorable one is encouraging."
"This combination regimen was chosen to study the potential of a combined
modality biological therapy. Bevacizumab targets an important pro-angiogenic
protein, VEGF, which also inhibits dendritic cell (DC) maturation and function.
Provenge consists of DC loaded with a PAP/GM-CSF protein and is designed to
activate the cellular component of a patient's immune system to target and
destroy the cancer," said Rini. "We look forward to further studies to define
the potential role of this combination immunotherapy."

About Provenge

Provenge is an investigational therapeutic cancer vaccine developed by
Dendreon Corporation that is designed to stimulate a person's own immune system
against prostate cancer. It is developed through Dendreon's proprietary Antigen
Delivery Cassette(TM) technology, which utilizes a recombinant form of an
antigen found in 95 percent of prostate cancers, prostatic acid phosphatase
(PAP).

About Bevacizumab (Avastin(TM))

Bevacizumab is an investigational therapeutic monoclonal antibody developed by
Genentech, Inc. that works to inhibit Vascular Endothelial Growth Factor (VEGF).
The protein VEGF is involved in the formation of new blood vessels to tumors
(tumor angiogenesis) and the preservation of existing tumor blood vessels.

Het bedrijf Dendreon, gespecialiseerd in vaccins bij kanker timmert opzichtig aan de weg met veelbelovende onderzoeken. Zo kreeg ik onderstaand bericht doorgestuurd van een meneer - waarvoor hartelijk dank - die informatie had gevraagd voer een vaccin tegen prostaatkanker en dit was het antwoord. Dendreon heeft een garantie gekregen dat zij het vaccin onder de naam Provenge (zie hierboven ook studiepublicatie over Provenge gepresensenteerd op Asco op deze pagina) in fase III studies mogen gaan onderzoeken. Deze garantieverklaring betekent dat de toestemming hiervoor alleen nog een formaliteit is. Weer een stap verder om prostaatkanker onder controle te krijgen lijkt het. Voor OPS-leden hebben we de naam en direct e-mailadres/telefoonnummer van een contactpersoon bij Dendreon beschikbaar. Mailt u ons maar en we sturen u dit toe.

Dendreon receives binding agreement from FDA that pivotal Phase 3 trial
(D9902B) will serve as basis for Provenge(R) approval

Seattle, WA (June 11, 2003) - Dendreon Corporation (NASDAQ: DNDN) today
announced that the company has received a Special Protocol Assessment (SPA)
from the U.S. Food and Drug Administration (FDA) indicating that its pivotal
Phase 3 trial, D9902B, will serve as the basis for a Biologics License
Application for its lead investigational cancer vaccine, Provenge(R), for
the treatment of androgen independent prostate cancer.

The SPA is a binding written agreement that provides for sponsors to receive
official FDA evaluation on pivotal trials that will form the basis of final
approval. Through this process, Dendreon worked closely with the FDA to
ensure that the trial's design and planned analysis adequately addresses the
clinical, statistical and regulatory objectives.

"This is a significant achievement and confirms that the D9902B trial will
serve as the basis for approval of our lead product Provenge," said Mitchell
H. Gold, M.D., chief executive officer of Dendreon. "We look forward to
continuing our efforts to make Provenge available as soon as possible to the
prostate cancer patients who may benefit from this therapy."

"A treatment like Provenge offers hope to the hundreds of thousands of men
fighting prostate cancer," said John Page, president and CEO of Us Too!
International, the world's oldest and largest prostate cancer advocacy
organization. "There are few, if any, treatment options available for men
with androgen independent prostate cancer."

"The SPA provision and binding agreement we now have with the FDA solidifies
our regulatory pathway toward approval of Provenge," added Elizabeth Smith,
Dendreon's vice president of regulatory affairs.

About D9902B Phase 3 trial

The double blind, placebo controlled Phase 3 trial of Provenge is underway
and will enroll approximately 275 patients at more than 60 medical centers
throughout the United States. The current protocol for the Phase 3 trial was
amended following analysis of Dendreon's first completed Phase 3 trial of
Provenge, trial D9901. In that completed trial, patients with a Gleason
score of 7 or below were shown to benefit most from Provenge treatment.

To be eligible for the study, patients must have metastatic prostate cancer
that has progressed following hormone therapy and have a Gleason Score of 7
or lower. Patients must also be free of cancer-related pain. Patients will
receive a total of three immunotherapy treatments over 30 days. Each
treatment consists of an apheresis procedure to collect blood cells,
followed two days later by an infusion of dendritic cells containing
vaccine. Patients who receive placebo will have the option of receiving the
immunotherapy if their disease progresses during the study.

Previous Clinical Results

Previously announced results of the D9901 trial demonstrated significant
benefit from Provenge treatment for men with a Gleason score of 7 or less.
For these patients, there was a more than two-fold (2.2) delay in time to
disease progression versus those patients who received placebo (p value=
0.002). In addition, the patients receiving Provenge whose disease had not
progressed six months after randomization had a greater than eight-fold
advantage in progression-free survival compared to patients who received
placebo.

For patients with a Gleason score of 7 or less treated with Provenge, there
was a more than two-fold (2.6) delay in time to the development of
disease-related pain versus those patients who received placebo (p value =
.019). Provenge treatment also induced a highly significant T-cell mediated
immune response compared to placebo (p=0.0003), with Provenge treated
patients demonstrating an eight-fold increase in T-cell proliferation
compared to placebo. In addition, among men treated with Provenge, those
whose tumors were graded with a Gleason score of 7 or less developed a
median change in T-cell mediated immune response seven-fold greater than the
T-cell mediated immune response seen in Provenge-treated men whose tumors
were graded a Gleason score of 8 and higher (p=0.0065).

About Gleason Score

The Gleason score is the most commonly used prostate cancer scoring system
and is considered one of the most important prognostic indicators for
prostate cancer. The score is based on tissue findings throughout the
prostate that correlate with the aggressiveness of a tumor. High Gleason
scores are indicative of aggressive cancers and are not associated with a
favorable prognosis. In the androgen independent patient population
approximately 75 percent of the patients have a Gleason score of 7 or less.

About Provenge

Provenge is an investigational therapeutic cancer vaccine designed to
stimulate a person's own immune system against prostate cancer. It is
developed through Dendreon's proprietary Antigen Delivery Cassette(TM)
technology, which utilizes a recombinant form of an antigen found in 95
percent of prostate cancers, prostatic acid phosphatase (PAP).