Conditions: Prostate Cancer
Keywords: Angiogenesis Cancer Hormonal Therapy Prostate Thalidomide Prostate Cancer
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 159
Healthy volunteers: no

Brief summary:
This multi-center study will evaluate whether thalidomide can improve the effectiveness of the drugs leuprolide or goserelin in treating testosterone-dependent prostate cancer. Leuprolide and goserelin-both approved to treat prostate cancer-reduce testosterone production, which, in most patients, reduces the size of the tumor. Thalidomide, a drug used for many years to treat leprosy, blocks the growth of blood vessels that may be important to disease progression.

Patients 18 years or older with testosterone-dependent prostate cancer that has persisted or recurred after having had surgery, radiation therapy, or cryosurgery, but whose disease has not metastasized (spread beyond the prostate) may be eligible for this study. Candidates are screened with a medical history and physical examination, including blood tests, bone and computed tomography (CT) scans or other imaging studies.

Study participants are randomly assigned to one of two treatment groups. One group receives leuprolide or goserelin followed by thalidomide; the other receives leuprolide or goserelin followed by placebo (a look-alike pill with no active ingredients). Patients in both groups receive an injection of leuprolide or goserelin once a month for 6 months. After that time they take four capsules of either thalidomide or placebo once a day and remain on the drug until their prostate-specific antigen (PSA) level returns to what it was before beginning leuprolide or goserelin or to 5 nanograms per liter, whichever is lower.(PSA is a protein secreted by the prostate gland. Monitoring changes in levels of this protein can help evaluate tumor progression). At this point the entire procedure begins again, starting with leuprolide or goserelin treatment, but the experimental drug is switched; patients originally treated with thalidomide are crossed over to placebo, and patients originally treated with placebo are crossed over to thalidomide.

Patients are monitored periodically with the following tests and procedures:

Medical histories and physical examinations. Blood and urine tests to monitor thalidomide and PSA levels, the response to treatment, and routine laboratory values (e.g., cell counts and kidney and liver function).

Computed tomography (CT) and bone scans, and possibly other imaging tests to assess the tumor.

Electromyography (EMG) and nerve conduction studies, as needed. For electromyography, a thin needle is inserted into a few muscles and the patient is asked to relax or to contract the muscles.

Detailed description:
This is a double-blind randomized phase III study designed to determine if thalidomide can improve the efficacy of the luteinizing hormone releasing hormone (LHRH) agonist (leuprolide or goserelin) in hormone-responsive patients with a rising PSA after primary definitive therapy for prostate cancer. Patients with only a rising PSA will be randomized to LHRH agonist for six months followed by oral thalidomide 200 mg per day or placebo (phase A). At the time of PSA progression, an LHRH agonist will be restarted for six additional months. After six months, patients originally treated with thalidomide will be crossed over to placebo and patients originally treated with placebo will be crossed over to thalidomide and followed until PSA progression or the development of metastatic disease, whichever occurs first (Phase B). Additional information will be obtained on changes in the circulating levels of the following growth factors: basic fibroblast growth factor (bFGF), tumor necrosis factor (TNF), vascular endothelial growth factor (VEGF), and transforming growth factor beta (TGFbeta). Likewise we will monitor changes in testosterone and dihydrotestosterone (DHT) throughout the study. Neurological complications are the primary dose-limiting toxicity anticipated with chronic thalidomide administration.

Arms:
arm 1: Study participants are randomly assigned to one of two treatment groups. Participants received leuprolide or goserelin for 6 months. In period 1 participants received thalidomide orally 200 mg a day. Patients will be followed until PSA progression defined as prostate-specific antigen (PSA) level that returns to what it was before beginning leuprolide or goserelin or to 5 nanograms per liter, whichever is lower. The participants are returned to the leuprolide or goserelin treatment for 6 months. In period 2 participants received the placebo for thalidomide once a day. arm 2: Study participants are randomly assigned to one of two treatment groups. Participants received leuprolide or goserelin for 6 months. In period 1 participants received placebo for thalidomide. Patients will be followed until PSA progression defined as prostate-specific antigen (PSA) level that returns to what it was before beginning leuprolide or goserelin or to 5 nanograms per liter, whichever is lower. The participants are returned to the leuprolide or goserelin treatment for 6 months. In period 2 participants received thalidomide 200 mg once a day.

Interventions: intervention 1: Thalidomide intervention 2: leuprolide acetate intervention 3: goserelin intervention 4: Placebo
Intervention descriptions: intervention 1: Thalidomide 200 mg given orally every evening at 9pm. Treatment may continue indefinitely provided that there are no dose-limiting toxicity. intervention 2: Injections of leuprolide once a month for six months. intervention 3: Injections of Goserelin once a month for six months. intervention 4: Patients will receive the placebo if they initially received thalidomide. The starting dose of placebo 200 mg (four capsules of 100-50 mg capsules) orally once daily at bedtime.

Protocol document:
ICF_001.pdf: 

















Prot_000.pdf: