PRINCETON, N.J., June 5 /PRNewswire-FirstCall/ -- Cytogen Corporation today announced the presentation of data from two phase II clinical trials of QUADRAMET(R) (samarium Sm-153 lexidronam injection) in combination with docetaxel (Taxotere(R), Aventis Pharmaceuticals, a member of the Sanofi-Aventis Group) in patients with progressive hormone refractory prostate cancer and bone metastases. Findings from the investigator-sponsored studies indicate that the combination regimens, known as TAXSAM, are well tolerated, provide pain palliation, and demonstrate promising rates of clinical and biochemical responses. Results were presented at the 42nd Annual Meeting of the American Society of Clinical Oncology (ASCO) in Atlanta, Georgia and the 53rd Annual Meeting of the Society of Nuclear Medicine (SNM) in San Diego, California.
“The study results presented during these major medical conferences add to the growing clinical experience of the combination use of QUADRAMET and docetaxel,” said William Goeckeler, Ph.D., senior vice president of operations at Cytogen. “The safety data from these investigator-sponsored TAXSAM studies, in particular with regard to the manageable and reversible effects on white blood cells and platelets are relevant to the use of QUADRAMET in its approved palliative indication in a contemporary oncology setting where patients may be considered for concurrent or subsequent treatment with taxane-based chemotherapy. We look forward to the presentation and publication of data from researchers at several leading U.S. cancer centers who are currently conducting company-sponsored clinical studies evaluating a variety of doses and schedules for combining QUADRAMET with docetaxel and other potentially synergistic agents in a variety of tumor types.”
ASCO abstract #4608 titled “A phase II trial of docetaxel and samarium in patients with bone metastases from castration-refractory prostate cancer (CRPC) and a response or stabilization after induction docetaxel- estramustine.”
The objective of this investigator-sponsored phase II study is to evaluate the efficacy of maintenance treatment using QUADRAMET in combination with low dose docetaxel in hormone refractory prostate cancer patients with bone metastases that demonstrate prostate-specific antigen (PSA) response or stabilization after induction therapy with docetaxel plus estramustine.
Forty-three patients received induction chemotherapy consisting of docetaxel at a dose of 70 mg/m2 on day two plus estramustine at a dose of 10 mg/kg on days one through five in a cycle that was repeated every three weeks. Patients experiencing a response or stabilization after four cycles of induction therapy were switched to a maintenance regimen consisting of weekly low dose docetaxel (20 mg/m2) for six weeks plus a single injection of QUADRAMET (1 mCi/kg) during week one.
Of thirty-nine evaluable patients who received the maintenance therapy with QUADRAMET, PSA progression-free survival assessed at 7 months was achieved in 20 (51%) patients. Pain response in this group, defined as a decrease in pain intensity by at least two points on a ten-point pain visual analog scale (VAS) in patients with a baseline pain level greater or equal to two, was achieved in twenty out of twenty-nine (69%) patients at the end of the maintenance regimen. Data on overall survival are pending.
The authors concluded that maintenance therapy with QUADRAMET was feasible and well-tolerated with most patients experiencing a rapidly reversible and mild (grade one-two) thrombocytopenia five weeks after the regimen.
SNM abstract #297 titled “Early response and toxicity of 153Sm-EDTMP combined with docetaxel in patients with hormone-refractory metastatic prostate cancer.”
The objective of this investigator-sponsored phase II study is to evaluate the safety and efficacy of QUADRAMET in combination with docetaxel in hormone refractory prostate cancer patients with bone metastases. Twenty-three patients received a single injection of QUADRAMET (1 mCi/kg) and then at least six cycles of docetaxel at a dose of 75 mg/m2 every three weeks beginning four to six weeks later.
The mean PSA level for these patients was 105 ng/mL (median 171). Sixteen patients had more than ten metastatic bone lesions, four patients had three to nine metastatic bone lesions, and three patients had less than three metastatic bone lesions. Mean baseline pain score in this group was four, as defined by a ten-point pain VAS. Eighteen of the twenty-three patients received more than six cycles and five patients received less than six cycles of docetaxel. Four patients received two doses of QUADRAMET.
Seventeen of the twenty-three patients demonstrated PSA declines (two patients with declines of greater than 50% and fifteen patients with a decline between 20% and 50%). Progression of disease was observed in sixteen of the twenty-three patients at a median of thirty-eight weeks after QUADRAMET. Data on overall survival are pending.
Grade three toxicity of platelets and white blood cells were each observed in one of the twenty-three patients following administration of QUADRAMET and the hematologic toxicity following the administration of docetaxel was similar to that seen when the agent is administered alone.
The investigators concluded that combination therapy with QUADRAMET and docetaxel was feasible and well-tolerated with good pain relief and promising rates of response and time to progression.
About Prostate Cancer
Prostate cancer is the most common type of cancer found in American men, other than skin cancer. In 2006, the American Cancer Society estimates that there will be about 234,000 new cases of prostate cancer in the United States and that about 27,000 men will die from the disease. It is estimated that there are more than 2 million American men currently living with prostate cancer. Tests to determine the amount of prostate-specific antigen (PSA), a protein produced by the cells of the prostate gland, in the blood along with a digital rectal exam is used to help initially detect prostate cancer and is also used to monitor patients with a history of prostate cancer to see if the cancer has come back, or recurred.
About QUADRAMET
QUADRAMET is indicated for the relief of pain in patients with confirmed osteoblastic metastatic bone lesions that enhance on radionuclide bone scan. This press release describes clinical applications that differ from that reported in the QUADRAMET package insert.
QUADRAMET is an oncology product indicated for pain relief that pairs the targeting ability of a small molecule, bone-seeking phosphonate (EDTMP) with the therapeutic potential of radiation (samarium Sm-153). Skeletal invasion by prostate, breast, multiple myeloma, and other cancers often creates an imbalance between the normal process of bone destruction and formation. QUADRAMET selectively targets such sites of imbalance, thereby delivering radioactivity to areas of the skeleton that have been invaded by metastatic tumor.
QUADRAMET has demonstrated a range of characteristics that may be advantageous for the treatment of pain arising from metastatic bone disease, including early onset of pain relief (patients may experience pain relief within the first week with maximal relief generally occurring at three to four weeks after injection), predictable and reversible bone marrow toxicity or myelosuppression that tends to return to pretreatment levels after eight weeks, ease of administration, and length of pain relief, lasting an average of four months in responding patients. QUADRAMET is administered as a single intravenous injection, usually on an outpatient basis, and exhibits selective uptake in areas of bone formation with little or no detectable accumulation in soft tissue.
QUADRAMET Safety Profile
QUADRAMET causes bone marrow suppression. In clinical trials, white blood cell counts and platelet counts decreased to a nadir of approximately 40% to 50% of baseline in 123 (95%) of patients within 3 to 5 weeks after QUADRAMET, and tended to return to pretreatment levels by 8 weeks. Because of the unknown potential for additive effects on bone marrow, QUADRAMET should not be given concurrently with chemotherapy or external beam radiation therapy unless the clinical benefits outweigh the risks. Blood counts should be monitored weekly for at least 8 weeks, or until recovery of adequate bone marrow function. Non-hematologic adverse events that occurred in 5% or more of patients and greater than placebo were plain flare (7%), diarrhea (6%), infection (7%), spinal cord compression (6.5%), arrhythmias (5%), and hematuria (5%). Patients who receive QUADRAMET should be advised that for several hours following administration, radioactivity will be present in excreted urine. To help protect themselves and others in their environment, precautions need to be taken for 12 hours following administration.
A copy of the full prescribing information for QUADRAMET, including warnings, precautions, adverse events and other safety information, may be obtained in the U.S. from Cytogen Corporation by calling toll-free 800-833-3533 or by visiting the web site at http://www.cytogen.com, which is not part of this press release.
ABOUT CYTOGEN CORPORATION
Founded in 1980, Cytogen Corporation of Princeton, NJ is a biopharmaceutical company dedicated to improving the lives of patients with cancer by acquiring, developing and commercializing innovative molecules targeting the sites and stages of cancer progression. Cytogen’s marketed products include QUADRAMET(R) (samarium Sm-153 lexidronam injection), PROSTASCINT(R) (capromab pendetide) kit for the preparation of Indium In-111 capromab pendetide, and SOLTAMOX(TM) (tamoxifen citrate, oral solution 10mg/5mL) in the United States. Cytogen’s development pipeline consists of CYT-500, a therapeutic radiolabeled antibody targeting prostate-specific membrane antigen (PSMA), a protein highly expressed on the surface of prostate cancer cells and the neovasculature of solid tumors. Cytogen also has exclusive United States marketing rights to COMBIDEX(R) (ferumoxtran-10) for all applications, and the exclusive right to market and sell ferumoxytol (previously Code 7228) for oncology applications in the United States. Full prescribing information for the Company’s products is available at http://www.cytogen.com or by calling 800-833-3533. For more information, please visit the Company’s website at http://www.cytogen.com, which is not part of this press release.
This press release contains certain “forward-looking” statements within the meaning of the Private Securities Litigation Reform Act of 1995 and Section 21E of the Securities Exchange Act of 1934, as amended. All statements, other than statements of historical facts, included in this press release regarding our strategy, future operations, financial position, future revenues, projected costs, prospects, plans and objectives of management are forward-looking statements. Such forward-looking statements involve a number of risks and uncertainties and investors are cautioned not to put any undue reliance on any forward-looking statement. There are a number of important factors that could cause Cytogen’s results to differ materially from those indicated by such forward-looking statements. In particular, Cytogen’s business is subject to a number of significant risks, which include, but are not limited to: the risk of obtaining the necessary regulatory approvals; the risk of whether products result from development activities; the risk of shifts in the regulatory environment affecting sales of Cytogen’s products such as third-party payor reimbursement issues; the risk associated with Cytogen’s dependence on its partners for development of certain projects, as well as other factors expressed from time to time in Cytogen’s periodic filings with the Securities and Exchange Commission (the “SEC”). As a result, this press release should be read in conjunction with Cytogen’s periodic filings with the SEC. The forward-looking statements contained herein are made only as of the date of this press release, and Cytogen undertakes no obligation to publicly update such forward-looking statements to reflect subsequent events or circumstances.
Cytogen Corporation
CONTACT: Media/Investors contact: Brian Korb, The Trout Group,+1-212-477-9007 x23, for Cytogen Corporation
Web site: http://www.cytogen.com/
