Once-yearly Histrelin Implant Provides Sustained Improvement in Prostate Cancer Patients
BARCELONA—Investigators have documented the long-term efficacy and tolerability of a once-yearly histrelin subdermal implant in men with advanced prostate cancer.
Histrelin acetate, a synthetic luteinizing hormone-releasing hormone (LHRH) agonist, is available as an implant and is inserted subcutaneously under local anesthesia during an office-based procedure. After 12 months, the implant is removed, and another implant may then be inserted, if indicated.
Neal D. Shore, MD, FACS, with Carolina Urologic Research Center/Atlantic Urology Clinics in Myrtle Beach, South Carolina, reported the findings of an extension trial that included 138 patients assigned to the histrelin arm in the original 52-week, phase 3 registration study. All men enrolled in the extension trial had achieved the primary end point of testosterone suppression at 4 weeks in the phase 3 trial.
The histrelin subdermal implants, which were replaced every 12 months, maintained the testosterone suppression initially documented at 1 year for a full 4 years without evidence of surge in serum testosterone. The most common side effects were mild-to-moderate hot flashes.
Because histrelin only needs to be replaced every 12 months, the implant may be preferable to other LHRH agonists, which are usually given by injection and need to be repeated at 1-, 3-, 4-, or 6-month intervals, he said.
Shore presented the data at the 25th Anniversary European Association of Urology (EAU) Annual Congress.
Zoledronic Acid Boosts Survival in Multiple Myeloma Patients
BARCELONA—Zoledronic acid improves survival in newly diagnosed multiple myeloma (MM) patients compared with clodronate, investigators announced at the 15th Congress of the European Hematology Association (EHA).
Their study also found that zoledronic acid was associated with a larger decrease in skeletal-related events (SREs).
Zoledronic acid’s survival advantage was independent of the SRE reduction.
The results are from the phase 3 Medical Research Council Myeloma IX study, which was conducted by a UK group.
Principal investigator Gareth J. Morgan, MD, with the Institute of Cancer Research in London, said that the findings bolster earlier preclinical studies suggesting anticancer activity for zoledronic acid.
In the study, newly diagnosed MM patients were randomized to intravenous zoledronic acid (4 mg, dose-adjusted based on renal function) every 3 to 4 weeks plus first-line chemotherapy or to daily oral clodronate (1600 mg) plus first-line chemotherapy.
Bone disease is common in MM patients, and bisphosphonates are widely used to prevent or treat bone disease in this population, Morgan pointed out. About 70% of patients in each treatment group had bone disease.
Patients continued treatment with their assigned bisphosphonate at least until disease progression.
A total of 1960 patients were evaluable, with a median follow-up of 3.7 years.
Zoledronic acid plus first-line chemotherapy significantly improved overall survival by 16%, with a 5.5-month difference in the median overall survival.
The percent of patients who experienced an SRE was decreased by 24% in patients receiving zoledronic acid versus clodronate. SKEs included bone fractures, radiation to bone, surgery to bone, and spinal cord compression.
Zoledronic acid’s survival benefit was maintained after controlling for the potential effect of SREs on survival. Both bisphosphonates were generally well tolerated.
“Our findings provide evidence that zoledronic acid should be considered for early integration into treatment regimens in patients with newly diagnosed MM,” Morgan said.
Deferasirox Treatment Provides Ongoing Benefit in Beta-thalassemia and Myocardial Siderosis
BARCELONA—Continued therapy with deferasirox over 2 years is effective in removing cardiac iron in beta-thalassemia patients with cardiac siderosis and is also well tolerated, according to data released at the 15th Congress of the European Hematology Association (EHA).
Dudley J. Pennell, MD, FRCP, FACC, with the Royal Brompton Hospital in London, United Kingdom, presented results in 82 heavily transfused beta-thalassemia patients with myocardial siderosis who had completed a 1-year trial of deferasirox and then continued treatment for an additional year.
“Iron chelation therapy has markedly improved survival for many regularly transfused patients with beta-thalassemia; however, heart failure due to cardiac iron deposition has been a leading cause of death,” Pennell said. “While the efficacy of chelation in reducing cardiac iron has been demonstrated using myocardial T2* in several prospective clinical trials of up to 1 year, longer term data are needed since T2* normalization may take several years.”
Deferasirox was started at 30 mg/ kg/day and increased to 40 mg/kg/day by the time patients entered the trial’s extension phase. Dose decreases were allowed for safety reasons.
The data showed that continued treatment with monotherapy deferasirox at greater than 30 mg/kg/day for up to 2 years significantly improved cardiac T2* and allowed 57% of patients with moderate-to-mild baseline cardiac siderosis to normalize and 43% of patients with severe baseline cardiac siderosis to achieve moderate-to-mild cardiac T2* values.
The investigators also found that significant improvements in cardiac T2* over 2 years were associated with the maintenance of normal cardiac function.
Deferasirox treatment was well tolerated.
The findings are especially noteworthy considering that all patients had received chelation therapy with other agents for a median of 12.2 years before enrolling in the study, Pennell said.
The study is the first to report 2-year data on cardiac iron removal for any iron-chelating agent, he added.