WARNING
Immediate-onset systemic allergic reactions, some resulting in hypotension and syncope, have occurred after administration of Plenaxis®. These immediate-onset reactions have been reported to occur following any administration of Plenaxis®, including after the initial dose. The cumulative risk of such a reaction increases with the duration of treatment (see WARNINGS). Following each injection of Plenaxis®, patients should be observed for at least 30 minutes in the office and in the event of an allergic reaction, managed appropriately.
- Only physicians who have enrolled in the Plenaxis® PLUS Program (Plenaxis® User Safety Program), based on their attestation of qualifications and acceptance of prescribing responsibilities, may prescribe Plenaxis® (See DOSAGE AND ADMINISTRATION and HOW SUPPLIED).
- Plenaxis® is indicated for the palliative treatment of men with advanced symptomatic prostate cancer, in whom LHRH agonist therapy is not appropriate and who refuse surgical castration, and have one or more of the following: (1) risk of neurological compromise due to metastases, (2) ureteral or bladder outlet obstruction due to local encroachment or metastatic disease, or (3) severe bone pain from skeletal metastases persisting on narcotic analgesia.
- The effectiveness of Plenaxis® in suppressing serum testosterone to castrate levels decreases with continued dosing in some patients (see CLINICAL PHARMACOLOGY, Pharmacodynamics). Effectiveness beyond 12 months has not been established. Treatment failure can be detected by measuring serum total testosterone concentrations just prior to administration on Day 29 and every 8 weeks thereafter (see WARNINGS).
|
|
| |
PLENAXIS SUMMARY
Abarelix for injectable suspension (Plenaxis®) is a synthetic decapeptide with potent antagonistic activity against naturally occurring gonadotropin releasing-hormone (GnRH).
Plenaxis® is indicated for the palliative treatment of men with advanced symptomatic prostate cancer, in whom LHRH agonist therapy is not appropriate and who refuse surgical castration, and have one or more of the following: (1) risk of neurological compromise due to metastases, (2) ureteral or bladder outlet obstruction due to local encroachment or metastatic disease, or (3) severe bone pain from skeletal metastases persisting on narcotic analgesia.
|
PLENAXIS NEWS HIGHLIGHTS Media Articles Related to Plenaxis (Abarelix)
Advanced Prostate Cancer - New Review On PROSTVAC(TM) Published By Key Investigators From NCI
Source: Cancer / Oncology News From Medical News Today [2009.07.02]
A just published Review in the publication "Expert Opinion on Investigational Drugs", Volume 18, Issue 7 2009, confirms the previous published information on PROSTVAC(TM). This is the most comprehensive and updated Review on PROSTVAC(TM) so far.
Prostate Cancer Screening Has Yet To Prove Its Worth
Source: IT / Internet / E-mail News From Medical News Today [2009.06.30]
The recent release of two large randomized trials suggests that if there is a benefit of screening, it is, at best, small, says a new report in CA: A Cancer Journal for Clinicians. Authored by Otis W. Brawley, M.D. of the American Cancer Society and Donna Ankerst, Ph.D. and Ian M. Thompson, M.D.
Prostate Cancer Screening Benefits Are Small, Says US Report
Source: Medical Devices / Diagnostics News From Medical News Today [2009.06.29]
The recently released results of two large randomized trials suggest there are no big benefits from prostate cancer screening, and if anything, they are quite small, says a new report by US researchers. And an accompanying editorial goes so far as to suggest that while screening has doubled the risk of a diagnosis, it has done little to reduce the risk of death from prostate cancer.
Routine Prostate Cancer Screening Not Clearly Worthwhile (CME/CE, with audio)
Source: MedPage Today Hematology [2009.06.29]
SAN FRANCISCO (MedPage Today) -- Widespread prostate cancer screening substantially increases diagnoses without much evidence for a survival benefit, a review found.
Selenium Intake May Worsen Prostate Cancer In Some
Source: Prostate / Prostate Cancer News From Medical News Today [2009.06.26]
Higher selenium levels in the blood may worsen prostate cancer in some men who already have the disease, according to a study by researchers at Dana-Farber Cancer Institute and the University of California, San Francisco. A higher risk of more-aggressive prostate cancer was seen in men with a certain genetic variant found in about 75 percent of the prostate cancer patients in the study.
Published Studies Related to Plenaxis (Abarelix)
A phase 3, multicenter, open label, randomized study of abarelix versus leuprolide plus daily antiandrogen in men with prostate cancer. [2002.04]
PURPOSE: We compared the endocrinological and biochemical efficacy of abarelix [generic for Plenaxis] depot, a gonadotropin-releasing hormone antagonist, with that of a widely used combination of luteinizing hormone releasing hormone agonist and a nonsteroidal antiandrogen... CONCLUSIONS: Abarelix as monotherapy achieves medical castration significantly more rapidly than combination therapy and avoids the testosterone surge characteristic of agonist therapy. Both treatments were equally effective in reducing serum prostate specific antigen, and achieving and maintaining castrate levels of testosterone.
A phase 3, multicenter, open-label, randomized study of abarelix versus leuprolide acetate in men with prostate cancer. [2001.11]
OBJECTIVES: To evaluate the levels of testosterone and other hormones in men with prostate cancer treated with abarelix [generic for Plenaxis] versus leuprolide acetate... CONCLUSIONS: Treatment with abarelix produced a higher percentage of patients who avoided a testosterone surge and had a more rapid time to testosterone suppression with a higher rate of medical castration 1 day after treatment and greater reductions in testosterone, luteinizing hormone, follicle-stimulating hormone, and dihydrotestosterone during the first 2 weeks of treatment compared with leuprolide acetate. The achievement and maintenance of castration was comparable between the two groups.
Abarelix for injectable suspension: first-in-class gonadotropin-releasing hormone antagonist for prostate cancer. [2006.12]
Abarelix [generic for Plenaxis], a gonadotropin-releasing hormone antagonist, with its indication for advanced symptomatic prostate cancer, represents the newest category of hormonal therapy introduced in the past 15 years. Results from Phase II and III clinical trials demonstrate the advantages of abarelix over commonly used luteinizing hormone-releasing hormone (LHRH) agonist therapy: abarelix does not cause a surge in serum testosterone that can precipitate a flare phenomenon or worsening of disease, particularly dangerous for patients with metastatic, symptomatic disease, and produces medical castration more quickly...
Dose-escalated abarelix in androgen-independent prostate cancer: a phase I study. [2006.10]
Follicle-stimulating hormone has been shown to be a mitogen in preclinical models of androgen-independent prostate cancer and abarelix [generic for Plenaxis] has been previously shown to significantly reduce follicle-stimulating hormone levels in patients when administered monthly. Consequently, we evaluated the safety of more frequent (biweekly) dosing of abarelix and characterized the effect of this dosing schedule on serum follicle-stimulating hormone levels in men with prostate cancer that is progressing despite luteinizing hormone-releasing hormone agonist therapy...
Abarelix: the first gonadotrophin-releasing hormone antagonist for the treatment of prostate cancer. [2004.10]
The high incidence of prostate cancer makes it a major healthcare problem and the second leading cancer-related cause of death among men in developed countries.The place of GnRH antagonists in the treatment modalities of prostate cancer will then be discussed.
Clinical Trials Related to Plenaxis (Abarelix)
The Plenaxis® Experience Study [Suspended]
Praecis is currently conducting a 2000 patient Experience Study; this is a Phase IV
commitment postmarketing safety study in the Food and Drug Administration (FDA) indicated
population of patients receiving Plenaxis®. The purpose of the study is to estimate the
incidence of immediate-onset systemic allergic reactions in the indicated population
receiving Plenaxis® and to determine whether the hazard rate changes over time.
Study of Abarelix in Androgen-Independent Prostate Cancer Progressing After Agonist Therapy [Completed]
This is a Phase 2, open-label study in subjects with androgen-independent prostate cancer who
have progressed following treatment with an LHRH agonist. Up to 22 subjects will be
enrolled. Enrollment will be monitored to ensure that not all subjects are enrolled based on
rising prostate specific antigen (PSA) criterion only.
Subjects will be treated with abarelix (Plenaxis) 100 mg intramuscularly (IM) every 2 weeks
for 12 weeks (total dose of 600 mg).
|
|
|
|
Page last updated: 2009-07-02
|
