Another round of encouraging, but fuzzier, interim data, this time for prostate canccer:
>>FOSTER CITY, Calif., May 14 /PRNewswire/ -- Cell Genesys, Inc. (Nasdaq: CEGE - news) today announced an encouraging update on Phase II clinical trials of the company's GVAX® prostate cancer vaccine product. In a trial of the vaccine in 55 patients who failed hormone therapy, there was a trend toward increased median time to progression measured by both bone scan and PSA (prostate-specific antigen) in patients receiving a higher dose of the vaccine compared to the lower dose. The median time to clinical progression achieved with the higher dose is comparable to that seen with the chemotherapy typically used to treat such patients. In the second trial in 41 early-stage prostate cancer patients with increasing PSA measurements following surgery, the median time to clinical progression has not been reached and patient follow-up is continuing. These data were presented at the American Society for Clinical Oncology (ASCO) Meeting on behalf of GVAX® Prostate Cancer Vaccine Clinical Investigators by William Nelson, M.D., Ph.D. of Johns Hopkins School of Medicine.
``We are encouraged by the initial Phase II data in advanced prostate cancer patients indicating the comparability of the higher vaccine dose to standard chemotherapy, and are equally encouraged by the consistency of the results across the clinical and PSA endpoints,'' stated Joseph J. Vallner, Ph.D., executive vice president and chief operating officer of Cell Genesys. ``In view of these findings, we have recently launched a new series of Phase I/II trials for a high potency GVAX® prostate cancer vaccine product and are targeting Phase III trials in late 2002.''
In December 2000, Cell Genesys reported preliminary Phase II data from a trial of the company's GVAX® prostate cancer vaccine in patients with advanced metastatic prostate cancer who have failed hormone therapy. Post treatment follow-up of the patients with positive bone scans prior to treatment revealed a trend toward prolonged time to progression as measured by bone scan in patients who received the higher dose of vaccine as compared to patients who received the lower dose (median time to progression of 140 days v. 85 days). The median time to progression for patients who failed hormone therapy but did not have positive bone scans at study entry was 179 days. Treatment with GVAX® vaccine was safe and well tolerated.
The reported Phase II studies employed a six month treatment regimen for GVAX® prostate cancer vaccine. The advanced patients who failed hormone treatment received an initial ``priming'' dose followed by 12 biweekly ``booster'' doses using either a low dose or three-fold higher dose regimen. The early-stage patients also received a priming dose and 12 biweekly booster doses using the low dose regimen. No other cancer therapies were administered during either the treatment or post treatment follow-up period. GVAX® prostate cancer vaccine was administered by an intradermal injection into the skin of the arms and legs and was safely administered in the outpatient setting. No serious or dose-limiting toxicities related to vaccine treatment were observed.
The efficacy endpoint used in the study with hormone-refractory patients-disease progression as measured by bone scan-is a clinical measure of the efficacy of GVAX® prostate cancer vaccine. This trial is the first Phase II trial conducted by Cell Genesys using this endpoint. Prior to initiating a Phase III trial, Cell Genesys is conducting a series of Phase I/II clinical trials evaluating a new high potency version of GVAX® prostate cancer vaccine which is approximately five to tenfold more potent than the first-generation vaccine tested in the aforementioned Phase II trials. In addition, the company plans to test this product in combination with chemotherapy since future Phase III trials in hormone refractory prostate cancer patients may compare GVAX® vaccine in combination with chemotherapy to chemotherapy alone.
In preparation for larger scale clinical studies, Cell Genesys is constructing a 41,000 square foot manufacturing facility in nearby Hayward, Calif., which will be used primarily for the manufacturing of multiple GVAX® cancer vaccine products for large scale clinical trials and potential market launch. The new GMP (Good Manufacturing Practices) facility is expected to be on-line by late 2002 in time for the initiation of Phase III trials.
GVAX® cancer vaccines are treatment vaccines comprised of tumor cells which have been irradiated and genetically modified to secrete granulocyte-macrophage colony stimulating factor (GM-CSF), a hormone which plays a key role in stimulating the body's immune response to vaccines. The genetically modified tumor cells are used to vaccinate patients to stimulate an immune response against their tumor. GVAX® cancer vaccines have demonstrated antitumor effects in each of the human clinical trials they have been tested in to date -- prostate cancer, pancreatic cancer, lung cancer, renal cancer and melanoma. The company's GVAX® cancer vaccine program, including GVAX® prostate cancer vaccine, emphasizes a non patient-specific form of the vaccine which could be commercialized as an off-the-shelf pharmaceutical product.<<
snip
Cheers, Tuck |
