Pharmacokinetic and pharmacodynamic comparison of subcutaneous versus intramuscular leuprolide acetate formulations in male subjects.

BACKGROUND: The aim of this study was to compare the pharmacokinetics (PK) and pharmacodynamics (PD) of two distinct formulations of leuprolide acetate (LA); subcutaneous (SC) injection and intramuscular (IM) injection. METHODS: A total of 32 healthy men were randomized to receive a single 7.5 mg injection of SC-LA (n = 16) or IM-LA (n = 16) in this phase I, open-label, parallel-group study. PK was assessed via LA concentrations, and PD via serum luteinizing hormone (LH) and testosterone (T) concentrations. RESULTS: The initial surge of LA was higher for IM-LA than SC-LA (Cmax 27 ± 4.9 versus 19 ± 8.0 ng/ml, respectively), with a shorter tmax (1.0 ± 0.4 versus 2.1 ± 0.8 h). The duration of quantifiable LA concentration was longer for SC-LA (up to 56 versus 42 days for SC-LA and IM-LA, respectively). Median LH concentrations in both groups rapidly increased, followed by gradual decrease. However, SC-LA demonstrated a longer duration of LH suppression, with median levels remaining below 1.0 IU/l through Day 56 compared with IM-LA where LH started to rise by Day 35. Consequently, serum T began to increase by Day 42 in the IM-LA group, with only four subjects maintaining levels ⩽50 ng/dl, compared with 14 subjects in the SC-LA group. By Day 56, 13 SC-LA subjects maintained serum T levels ⩽50 ng/dl. Both SC-LA and IM-LA were well tolerated. CONCLUSIONS: Both formulations demonstrated consistent delivery of drug over 1 month; however, SC-LA provided a longer duration of action than expected based on the dosing interval. This profile suggests that SC-LA will provide effective suppression of T over a longer period of time, permitting greater injection scheduling flexibility.

Polymer-delivered subcutaneous leuprolide acetate formulations achieve and maintain castrate concentrations of testosterone in four open-label studies in patients with advanced prostate cancer.

OBJECTIVE: To determine whether luteinising hormone-releasing hormone (LHRH) agonist, ATRIGEL® polymer-delivered, subcutaneous, leuprolide acetate (ADSC-LA), formulations suppressed serum testosterone to concentrations of ≤20 ng/dL. PATIENTS AND METHODS: Data from four open-label, fixed-dose studies were evaluated. Male patients aged 40-86 years with advanced prostatic adenocarcinoma, whom had not undergone prior androgen-deprivation therapy (ADT), were treated with a depot formulation of ADSC-LA: 7.5 mg (1-month, 120 patients), 22.5 mg (3-month, 117 patients), 30 mg (4-month, 90 patients), or 45 mg (6-month, 111 patients). Serum testosterone was sampled at screening, baseline, 2, 4, 8 h after dosing, 1, 2, 3, and 7 days, and every week until the next dose, at which time, the sampling schedule repeated until the end of study (24 weeks for 1- and 3-month formulations, 32 weeks for 4-month, and 48 weeks for the 6-month). The primary analyses were mean serum testosterone concentrations and proportion of patients who achieved concentrations of ≤20 ng/dL. RESULTS: The mean (SE) serum testosterone concentrations at the end of study were consistently ≤20 ng/dL in each study, at 6.1 (0.4), 10.1 (0.7), 12.4 (0.8), and 12.6 (2.1) ng/dL for the 1-, 3-, 4-, and 6-month formulations, respectively. A high proportion of patients (94%, 90%, 92%, 96% for the 1-, 3-, 4-, and 6-month formulations, respectively) achieved testosterone concentrations of ≤20 ng/dL within 6 weeks, and 90-97% of patients in all studies maintained concentrations of ≤20 ng/dL from weeks 6-24. CONCLUSIONS: Recent studies have shown improved outcomes in patients with prostate cancer who consistently attained a more rigorous level of testosterone suppression (≤20 ng/dL) with ADT than the historical standard (≤50 ng/dL). All doses of ADSC-LA rapidly achieved and maintained mean serum testosterone to the more rigorous target concentration of ≤20 ng/dL. These data suggest that ADSC-LA delivers equivalent testosterone suppression as achieved by surgical castration.

Androgen Receptor Modulation Optimized for Response (ARMOR) Phase I and II Studies: Galeterone for the Treatment of Castration-Resistant Prostate Cancer.

PURPOSE: Galeterone is a selective, multitargeted agent that inhibits CYP17, antagonizes the androgen receptor (AR), and reduces AR expression in prostate cancer cells by causing an increase in AR protein degradation. These open-label phase I and II studies [Androgen Receptor Modulation Optimized for Response-1 (ARMOR1) and ARMOR2 part 1] evaluated the efficacy and safety of galeterone in patients with treatment-naive nonmetastatic or metastatic castration-resistant prostate cancer (CRPC) and established a dose for further study. EXPERIMENTAL DESIGN: In ARMOR1, 49 patients received increasing doses (650-2,600 mg) of galeterone in capsule formulation; 28 patients in ARMOR2 part 1 received increasing doses (1,700-3,400 mg) of galeterone in tablet formulation for 12 weeks. Patients were evaluated biweekly for safety and efficacy, and pharmacokinetic parameters were assessed. RESULTS: In ARMOR1, across all doses, 49.0% (24/49) achieved a ≥30% decline in prostate-specific antigen (PSA; PSA30) and 22.4% (11/49) demonstrated a ≥50% PSA decline (PSA50). In ARMOR2 part 1, across all doses, PSA30 was 64.0% (16/25) and PSA50 was 48.0% (12/25). In the 2,550-mg dose cohort, PSA30 was 72.7% (8/11) and PSA50 was 54.5% (6/11). Galeterone was well tolerated; the most common adverse events were fatigue, increased liver enzymes, gastrointestinal events, and pruritus. Most were mild or moderate in severity and required no action and there were no apparent mineralocorticoid excess (AME) events. CONCLUSIONS: The efficacy and safety from ARMOR1 and ARMOR2 part 1 and the pharmacokinetic results support the galeterone tablet dose of 2,550 mg/d for further study. Galeterone was well tolerated and demonstrated pharmacodynamic changes consistent with its selective, multifunctional AR signaling inhibition.

A randomised, double-blind study comparing the addition of bicalutamide with or without dutasteride to GnRH analogue therapy in men with non-metastatic castrate-resistant prostate cancer.

BACKGROUND: Bicalutamide blocks androgen action and is frequently used in men with non-metastatic, castration-resistant prostate cancer (CRPC). By reducing intracellular dihydrotestosterone, dutasteride (dual 5-alpha reductase inhibitor) could increase the effectiveness of bicalutamide in this setting. The objective of the study is therefore to prospectively evaluate dutasteride plus bicalutamide in men with asymptomatic, non-metastatic CRPC with rising prostate-specific antigen (PSA). METHODS: Prostate cancer patients with rising PSA whilst on first-line androgen deprivation therapy (ADT) were randomised (1:1) in a double-blind trial to receive bicalutamide 50mg plus placebo or bicalutamide 50mg plus dutasteride 3.5mg once daily for 18 months. Randomisation was stratified by centre; treatment assignments were generated using GlaxoSmithKline's RandAll System. Subjects who completed 18 months could participate in the 2-year extension. Central laboratory and study sites/monitors remained treatment-blinded. Primary end-point was time to disease progression (TDP) up to 42 months (defined as PSA progression from baseline or nadir, radiographic disease progression, death from prostate cancer or receipt of rescue medication). FINDINGS: There was no statistically significant difference in TDP in 127 men treated with bicalutamide/dutasteride (n=62) compared with bicalutamide/placebo (n=65) (hazard ratio (HR)=0.94 [95% confidence interval (CI) 0.61, 1.46]; p=0.79). The estimated median TDP was 425 days (95% CI 302, 858) in the bicalutamide/placebo group and 623 days (95% CI 369, 730) in the bicalutamide/dutasteride group. There was no statistically significant difference between the treatment groups for any secondary efficacy end-points, including time to treatment failure or PSA response. In the multivariate analysis, age, non-White race, higher baseline testosterone and lower baseline PSA were associated with longer TDP. Adverse events were comparable between treatment groups. INTERPRETATION: In men with non-metastatic CRPC, adding dutasteride to bicalutamide did not significantly prolong TDP. Prospective data are provided concerning the common practice of using bicalutamide in this setting.

Selective estrogen receptor alpha agonist GTx-758 decreases testosterone with reduced side effects of androgen deprivation therapy in men with advanced prostate cancer.

BACKGROUND: A need remains for new therapeutic approaches for men with advanced prostate cancer, particularly earlier in the disease course. OBJECTIVE: To assess the ability of an oral selective estrogen receptor α agonist (GTx-758) to lower testosterone concentrations compared with leuprolide while minimizing estrogen deficiency-related side effects of androgen-deprivation therapy. DESIGN, SETTING, AND PARTICIPANTS: Hormone-naive advanced prostate cancer patients were randomized to oral GTx-758 1000 mg/d, 2000 mg/d, or leuprolide depot. INTERVENTION: GTx-758 and leuprolide. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary end point was the proportion of patients achieving total testosterone ≤ 50 ng/dl by day 60. Secondary end points included serum free testosterone, prostate-specific antigen (PSA), sex hormone-binding globulin, hot flashes, bone turnover markers, and insulin-like growth factor (IGF)-1 levels. RESULTS AND LIMITATIONS: Of 159 randomized patients, leuprolide reduced total testosterone to ≤ 50 ng/dl in a greater proportion of patients than GTx-758 by day 60 (43.4%, 63.6%, and 88.2% of subjects receiving GTx-758 1000 mg [p<0.001], GTx-758 2000 mg [p=0.004], and leuprolide, respectively). GTx-758 reduced free testosterone and PSA earlier and to a greater degree than leuprolide. GTx-758 led to fewer hot flashes, decreases in bone turnover markers, and alterations in IGF-1 compared with leuprolide. A higher incidence of venous thromboembolic events (VTEs) was seen with GTx-758 (4.1%) compared with leuprolide (0.0%). CONCLUSIONS: Although leuprolide reduced total testosterone to ≤ 50 ng/dl in a greater proportion of patients compared with GTx-758, GTx-758 was superior in lowering free testosterone and PSA. GTx-758 reduced estrogen deficiency side effects of hot flashes, bone loss, and insulin resistance but with a higher incidence of VTEs. PATIENT SUMMARY: This paper reports findings that leuprolide lowered total testosterone more than GTx-758 but that GTx-758 lowered free testosterone and prostate-specific antigen more than leuprolide. GTx-758 also reduced estrogen deficiency side effects, albeit at a higher rate of vascular events. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT01615120.

Vaccination of castration-resistant prostate cancer patients with TroVax (MVA-5T4) in combination with docetaxel: a randomized phase II trial.

The attenuated vaccinia virus, modified vaccinia Ankara, has been engineered to deliver the tumor antigen 5T4 (TroVax®). Here, we report results from a randomized open-label phase II trial in castration-resistant prostate cancer patients in which TroVax was administered in combination with docetaxel and compared against docetaxel alone. The aim was to recruit 80 patients (40 per arm), but the study was terminated early due to recruitment challenges. Therefore, this paper reports the comparative safety and immunological and clinical efficacy in 25 patients, 12 of whom were treated with TroVax plus docetaxel and 13 with docetaxel alone. 5T4-specific immune responses were monitored throughout the study. Clinical responses were assessed by measuring changes in tumor burden by CT and bone scan and by quantifying PSA concentrations. TroVax was well tolerated in all patients. Of 10 immunologically evaluable patients, 6 mounted 5T4-specific antibody responses. Patients treated with TroVax plus docetaxel showed a greater median progression-free survival of 9.67 months compared with 5.10 months for patients on the docetaxel alone arm (P = 0.097; HR = 0.31; 95% CI 0.08-1.24). Importantly, a pre-treatment biomarker previously demonstrated to predict 5T4 immune response and treatment benefit showed a strong association with 5T4 antibody response and a statistically significant association with progression-free survival in patients treated with TroVax plus docetaxel, but not docetaxel alone.

Multicenter phase II trial of the heat shock protein 90 inhibitor, retaspimycin hydrochloride (IPI-504), in patients with castration-resistant prostate cancer.

OBJECTIVE: To evaluate clinical activity and safety of retaspimycin hydrochloride (IPI-504) in patients with castration-resistant prostate cancer (CRPC). METHODS: A single-arm trial was conducted in 2 cohorts: group 1, chemotherapy naive; group 2, docetaxel-treated. IPI-504 was administered intravenously at 400 mg/m2 on days 1, 4, 8, and 11 of a 21-day cycle. Trial expansion was planned if ≥1 prostate-specific antigen (PSA) or radiographic response was noted per cohort. Pharmacokinetic samples were collected after the first dose; safety was assessed throughout. RESULTS: A total of 19 patients were enrolled (4 in group 1; 15 in group 2), with a median age of 66 years (range 49-78). Group 2 had received a median of 2 previous chemotherapy regimens. All group 2 patients had bone metastases; 66% had measurable soft tissue or visceral metastases. One group 1 patient remained on-trial for 9 cycles; his PSA level declined 48% from baseline. No PSA response was observed in the other patients. Adverse events reported in >25% of the study population included nausea (47%), diarrhea (42%), fatigue (32%), anorexia (26%), and arthralgia (26%). Two patients in group 2 died on-trial, involving study drug-related events of hepatic failure and ketoacidosis, respectively. CONCLUSION: Heat shock protein 90 inhibition with IPI-504 administered as a single agent had a minimal effect on the PSA level or tumor burden and was associated with unacceptable toxicity in several patients. Therefore, additional evaluation in CRPC patients is not warranted. IPI-504 is being investigated at less-intensive doses and schedules in other tumor types.

A phase 1, multicenter, open-label study of the safety of two dose levels of a human monoclonal antibody to human α(v) integrins, intetumumab, in combination with docetaxel and prednisone in patients with castrate-resistant metastatic prostate cancer.

PURPOSE: We evaluated the safety and efficacy of intetumumab in combination with docetaxel in patients with castrate-resistant metastatic prostate cancer. Patients and methods In this phase 1, open-label, multicenter, nonrandomized study, 75 mg/m² docetaxel was administered on Day 1 of each of nine 21-day treatment cycles and intetumumab 5 or 10 mg/kg was administered on Days 1, 8, and 15 of Cycles 2 and 3 and on Day 1 of all subsequent cycles. The primary endpoint was the incidence of dose-limiting toxicities (DLTs) during Cycles 2 and 3. Secondary endpoints included serum prostate-specific antigen (PSA) response and objective response based on Response Evaluation Criteria in Solid Tumors (RECIST). RESULTS: Ten patients were treated (5 mg/kg n = 3, 10 mg/kg n = 7). No DLTs occurred. Most treatment-emergent adverse events (TEAEs) occurred in the 10-mg/kg intetumumab group. Common TEAEs were neutropenia (10 mg/kg n = 6) and nausea (5 mg/kg n = 1, 10 mg/kg n = 5). Four 10-mg/kg-treated patients reported serious TEAEs; of these, only febrile neutropenia was considered probably intetumumab-related. In the 10-mg/kg group, four patients had a serum PSA response (two of whom responded within 3 months of treatment), one patient demonstrated partial tumor response for 11 weeks, and none had progressive disease at Cycle 9. No PSA or tumor response was observed in the 5-mg/kg group. CONCLUSIONS: Intetumumab was generally safe and well tolerated in combination with docetaxel, with a higher incidence of TEAEs in the 10 mg/kg dose cohort. The efficacy of 10 mg/kg intetumumab in combination with docetaxel appears to warrant further study.

Delayed wound closure in fibromodulin-deficient mice is associated with increased TGF-ß3 signaling.

Fibromodulin (FMOD), a small leucine-rich proteoglycan, mediates scarless fetal skin wound repair through, in part, transforming growth factor-ß (TGF-ß) modulation. Using an adult fmod-null (fmod(-/-)) mouse model, this study further elucidates the interplay between FMOD and TGF-ß expression during cutaneous repair and scar formation. Full-thickness skin wounds on fmod(-/-) and wild-type (WT) mice were closed primarily and analyzed. Histomorphometry revealed delayed dermal cell migration leading to delayed wound closure and significantly increased scar size in fmod(-/-) mice relative to WT, which was partially rescued by exogenous FMOD administration. In addition, fmod(-/-) wounds exhibited early elevation (within 24 hours post-wounding) of type I and type II TGF-ß receptors as well as unexpectedly high fibroblast expression of TGF-ß3, a molecule with reported antifibrotic and antimigratory effects. Consistent with elevated fibroblastic TGF-ß3, fmod(-/-) fibroblasts were significantly less motile than WT fibroblasts. fmod(-/-) fibroblasts were also more susceptible to migration inhibition by TGF-ß3, leading to profound delays in dermal cell migration. Increased scarring in fmod(-/-) mice indicates that TGF-ß3's antimotility effects predominate over its antifibrotic effects when high TGF-ß3 levels disrupt early fibroblastic wound ingress. These studies demonstrate that FMOD presence is critical for proper temporospatial coordination of wound healing events and normal TGF-ß bioactivity.

Efficacy and safety of solifenacin succinate 10 mg once Daily: A multicenter, phase III, randomized, double-blind, placebo-controlled, parallel-group trial in patients with overactive bladder.

BACKGROUND: Solifenacin succinate is an antimuscarinic drug with reported efficacy and tolerability at a recommended starting dose of 5 mg QD in patients with overactive bladder (OAB). OBJECTIVE: The objective of this trial was to investigate the efficacy, safety, and tolerability of solifenacin 10 mg QD in patients with OAB. METHODS: In this multicenter, Phase III, double-blind, placebo-controlled, parallel-group trial, patients aged ≥18 years with OAB were randomized at a 1:1 ratio to receive solifenacin 10 mg or placebo QD for 12 weeks. The patients were instructed to complete a micturition diary for the 3 days preceding each scheduled visit (weeks 4, 8, and 12). The primary end point was the change from baseline in the mean number of micturitions per 24 hours; secondary end points included the mean change from baseline in the number of episodes per 24 hours of urgency, incontinence, nocturnal voiding, and nocturia and the mean volume voided per micturition. Tolerability was monitored through adverse events (AEs), vital sign measurements, ECGs, laboratory assessments, and physical examination. RESULTS: A total of 672 patients were randomized and received ≥1 dose of study drug (solifenacin, n = 340; placebo, n = 332). The mean (SE) decrease from baseline to study end in the number of micturitions per 24 hours was significantly greater in the solifenacin group compared with the placebo group (-3.0 [0.2] vs -1.5 [0.2], respectively; P < 0.001). The mean decrease in the number of episodes of incontinence was significantly greater in the solifenacin group compared with the placebo group (-2.0 [0.2] vs -1.1 [0.2]; P < 0.001), as was the mean decrease in the number of episodes of urgency (-4.1 [0.2] vs -2.1 [0.2]; P < 0.001). Of the patients with ≥1 incontinence episode per 24 hours at baseline, significantly more patients in the solifenacin group achieved complete continence at study end than did patients in the placebo group (119/225 [52.9%] vs 80/237 [33.8%]; P < 0.001). The change from baseline to study end in the mean volume voided per micturition increased significantly in the solifenacin group compared with the placebo group (47.2 vs 2.7 mL; P < 0.001). Most AEs were mild or moderate in intensity. The AEs that were most commonly reported in the solifenacin-treated group were anticholinergic in nature: dry mouth (91 [26.8%] vs 13 patients [3.9%] in the placebo group; P < 0.001); constipation (58 [17.1%] vs 11 [3.3%]; P < 0.001); and blurred vision (12 [3.5%] vs 4 [1.2%]; P < 0.05). Serious AEs (SAEs) were reported for 5 patients in the solifenacin group and 3 patients in the placebo group. In the solifenacin group, 2 patients experienced chest pain, 1 had cellulitis, 1 had dehydration, and 1 had colonic obstruction; only 1 SAE (colonic obstruction) was judged to be possibly related to the study drug. In the placebo group, 1 patient had chest pain, 1 had bacterial meningitis, and 1 had hemopericardium. CONCLUSIONS: This study found that solifenacin 10 mg QD for 12 weeks was associated with significantly reduced symptoms of OAB, including the frequency of micturition, and episodes of urgency and of incontinence. With solifenacin, the volume voided per micturition increased by 47.2 mL, and 53% of patients with ≥1 incontinence episode per 24 hours at baseline achieved complete continence. This efficacy was accompanied by a favorable safety and tolerability profile.

Toremifene improves lipid profiles in men receiving androgen-deprivation therapy for prostate cancer: interim analysis of a multicenter phase III study.

PURPOSE: Androgen-deprivation therapy (ADT) is associated with greater risk of incident coronary heart disease and hospital admission for myocardial infarction; treatment-related increases in serum lipids may contribute to greater cardiovascular disease risk. We evaluated the effects of toremifene, a selective estrogen-receptor modulator, on fasting serum lipid levels in men receiving ADT for prostate cancer. PATIENTS AND METHODS: In an ongoing, multicenter, double-blind, placebo-controlled phase III fracture-prevention study, 1,389 men receiving ADT for prostate cancer were randomly assigned to receive toremifene (80 mg/d) or placebo. In this interim analysis of 188 patients, changes in fasting serum lipids from baseline to month 12 were compared between the placebo and toremifene groups. RESULTS: Changes in serum lipids differed significantly between the groups. Mean (+/- SE) total cholesterol decreased by 1.0% +/- 1.7% from baseline to month 12 in the placebo group and decreased by 8.1% +/- 1.4% in the toremifene group (P = .001 for between group comparison). Low-density lipoprotein (LDL) cholesterol increased by 0.8% +/- 2.5% in the placebo group and decreased by 8.2% +/- 2.5% in the toremifene group (P = .003). In contrast, high-density lipoprotein (HDL) cholesterol decreased by 4.9% +/- 1.2% in the placebo group and increased by 0.5% +/- 2.2% in the toremifene group (P = .018). Triglycerides increased by 6.9% +/- 4.2% in the placebo group and decreased by 13.2% +/- 3.6% in the toremifene group (P = .003). CONCLUSION: Toremifene significantly decreased total cholesterol, LDL cholesterol, and triglycerides, and increased HDL cholesterol in men receiving ADT for prostate cancer.

Pathophysiology of overactive bladder.

Overactive bladder (OAB) is a complex of symptoms frequently encountered in the primary care setting. Impediments to optimal management of OAB include inaccurate perceptions on the part of patients and primary care providers, e.g., that the symptoms of OAB represent a natural progression of aging and are beyond the scope of treatment or that diagnosis and treatment are specialist concerns. Complicating the physician's task is the reluctance of many patients to initiate discussion of their OAB symptoms and the fact that patients often develop disruptive coping strategies rather than seek medical treatment, possibly because of a belief that OAB is a normal part of aging rather than an actual medical condition. In most cases, OAB may be managed quite well by the primary care physician who has an understanding of the pathophysiology of OAB. This article reviews normal bladder function and then explores pathophysiologic changes that likely cause the symptoms of OAB.

Management of overactive bladder and urge urinary incontinence in the elderly patient.

The symptoms of overactive bladder (OAB) and urge urinary incontinence may occur at any age but are particularly common among the elderly. These symptoms are associated with significant morbidity and often have a profound impact on patient quality of life. Urinary incontinence is an important contributor to the complications and economic cost of OAB for both community-dwelling and institutionalized elderly individuals. Many patients with OAB do not seek treatment because of embarrassment, fear of surgery, or the misperceptions that the problem is untreatable or is a normal and inevitable consequence of aging. Nonpharmacologic therapies improve bladder control by modifying lifestyle and behavior to prevent urine loss. This requires patient and caregiver motivation and can be time consuming. Improved results may be obtained by combining these strategies with pharmacotherapy or by means of pharmacotherapy alone. The most commonly used pharmacologic agents are the muscarinic receptor antagonists. These include oxybutynin, tolterodine, and three agents that have recently been approved for use in the United States: trospium, darifenacin, and solifenacin. In general, these therapies are well tolerated and safe; however, the selection of an optimal agent merits careful consideration. For elderly patients, important considerations include tolerability, absence of drug interactions, and the availability of a range of dosages to tailor treatment to individual patients. Primary care practitioners and geriatricians can have a key role in successful diagnosis and treatment of OAB. It is important for these physicians to realize that satisfactory outcomes may be achieved within the scope of a busy outpatient practice.

Management of incontinence for family practice physicians.

Family practice physicians are likely to encounter urinary incontinence and overactive bladder (OAB) in their patients. An informed family practice physician can generally accurately diagnose the cause and type of incontinence in patients with a properly focused physical examination and, if necessary, auxiliary testing. Accurate diagnosis can lead to effective treatment when physicians are familiar with available treatment options, including pharmacologic, surgical, behavioral therapies, and catheterization.

A 12-month clinical study of LA-2585 (45.0 mg): a new 6-month subcutaneous delivery system for leuprolide acetate for the treatment of prostate cancer.

PURPOSE: The safety, efficacy and pharmacokinetics of LA-2585, a new 6-month subcutaneous depot of leuprolide acetate (Atrix Laboratories, Fort Collins, Colorado) were investigated in patients with prostate cancer. MATERIALS AND METHODS: In this 12-month, open label, multicenter study 111 patients with adenocarcinoma of the prostate were administered 45.0 mg LA-2585 subcutaneously once every 6 months. The primary efficacy parameter was serum testosterone 50 ng/dl or less. Leuprolide acetate pharmacokinetics were analyzed in a subset of 28 patients. RESULTS: Of the 111 enrolled patients 103 (93%) completed the 12-month study. Eight patients withdrew due to nonmedical reasons in 1, disease progression in 5 and cardiovascular disease in 2. By day 28, 108 of the 109 remaining patients (99%) achieved testosterone suppression, while 1 who never attained suppression was withdrawn at day 85. Mean time to castrate suppression was 21.2 days (median 21). At study completion 102 of 103 patients (99%) were below medical castrate testosterone levels of 50 ng/dl (mean +/- SE 12.3 +/- 2.1 ng/dl) with 91 of 103 (88%) at less than 20 ng/dl. Mean luteinizing hormone decreased from 6.98 +/- 0.48 mIU/ml at baseline to 0.23 +/- 0.14 mIU/ml at month 12. Luteinizing hormone was consistently below 1 mIU/ml. Mean prostate specific antigen decreased 97% from 39.8 +/- 21.5 ng/ml at baseline to 1.2 +/- 0.3 ng/ml at 12 months. No clinically significant flare reactions were observed. The most common treatment related adverse event was mild to moderate hot flashes. CONCLUSIONS: LA-2585 (45.0 mg depot) consistently produced and maintained safe and effective serum testosterone suppression with total serum testosterone well below the medical castrate level of less than 50 ng/dl.

Extended-release formulations of oxybutynin and tolterodine exhibit similar central nervous system tolerability profiles: a subanalysis of data from the OPERA trial.

OBJECTIVE: This study was undertaken to compare the central nervous system (CNS) tolerability profiles of the extended-release formulations of oxybutynin chloride and tolterodine tartrate in the treatment of women with overactive bladder (OAB), as observed in the OPERA (Overactive bladder: Performance of Extended Release Agents) trial. STUDY DESIGN: The OPERA trial was a randomized, double-blind, active-control comparison of the efficacy and safety of extended-release oxybutynin (10 mg/d) and extended-release tolterodine (4 mg/d) given to 790 women with OAB for 12 weeks. The incidence of reported CNS events was compared between the treatment groups by using the Fisher exact test. RESULTS: The incidence of CNS adverse events was 9% and 8% for the oxybutynin and tolterodine treatment groups, respectively. The difference between groups was not statistically significant. All reported CNS adverse events were rated as mild or moderate in severity. There were no serious treatment-related adverse events in either group, and discontinuation because of a CNS adverse event was infrequent. CONCLUSION: The extended-release formulations of oxybutynin and tolterodine were observed to be associated with a similar low incidence of CNS adverse events, which were mostly mild or moderate in severity.

An eight-month clinical study of LA-2575 30.0 mg: a new 4-month, subcutaneous delivery system for leuprolide acetate in the treatment of prostate cancer.

OBJECTIVES: To investigate the safety, efficacy, and pharmacokinetics of a new 4-month subcutaneous depot of leuprolide acetate in patients with prostate cancer. METHODS: Ninety patients diagnosed with adenocarcinoma of the prostate were enrolled in an open-label, multicenter study. LA-2575 30.0 mg was administered subcutaneously once every 4 months for 8 months. The primary efficacy parameter was a serum testosterone level of 50 ng/dL or less. The pharmacokinetics of leuprolide acetate were analyzed in the first 24 enrolled patients. The values are reported as the mean +/- standard error. RESULTS: Of 90 enrolled patients, 82 (91%) completed the 8-month study. Eight patients voluntarily withdrew from the study for the following reasons: nonmedical reasons (n = 3), treatment-related adverse events (n = 3), disease progression (n = 1), and cardiovascular disease (n = 1). By day 28, 85 (94%) of the 90 patients had achieved a serum testosterone level less than 50 ng/dL. At study completion, 88 (98%) of the 90 patients had a testosterone value less than the castrate level (mean 12.4 +/- 0.8 ng/dL), with 81 (90%) at less than 20 ng/dL. From baseline to month 6, the mean luteinizing hormone level had decreased from 7.51 +/- 0.69 mIU/mL to 0.12 +/- 0.02 mIU/mL. The mean prostate-specific antigen level had decreased 90% from 13.2 +/- 2.0 ng/mL at baseline to 1.3 +/- 0.3 ng/mL at 8 months. No clinically significant flare reactions were observed. The most common treatment-related adverse event was mild hot flashes. CONCLUSIONS: LA-2575 30.0-mg depot consistently produced and maintained safe and effective suppression of serum testosterone, with total serum testosterone concentrations well below the medical castrate level of less than 50 ng/dL.

A six-month, open-label study assessing a new formulation of leuprolide 7.5 mg for suppression of testosterone in patients with prostate cancer.

OBJECTIVE: The safety, efficacy, and pharmacokinetics of monthly subcutaneous injections of a new leuprolide acetate (LA) depot formulation were investigated in patients with advanced prostate cancer. METHODS: The 2-part, 6-month (168-day), open-label, multicenter study enrolled male patients diagnosed with adenocarcinoma of the prostate (Jewett stage C or D). LA-2500 7.5-mg (a new subcutaneous depot formulation containing 7.5 mg of LA) injections were administered at monthly (28-day) intervals. The primary efficacy parameter was total serum testosterone level. A breakthrough response was defined as a single testosterone measurement > 50 ng/dL after achieving castration testosterone levels. Testosterone was isolated from sera by alumina column chromatography and measured by radioimmunoassay (RIA). LA was purified by solid-phase extraction and high-performance liquid chromatography and was then quantitated by RIA. RESULTS: One hundred seventeen of the 120 enrolled patients completed the 6-month study. Three patients withdrew for reasons not related to treatment. LA had a mean (SD) maximal concentration of 26.3 (12.6) ng/mL at 4.66 (1.44) hours and was detected for a mean of 37 days (range, 28-49 days). By day 28, 94.1% (112/119) of the patients achieved medical castration (serum testosterone < or = 50 ng/dL). By day 42, 100.0% (118/118) of the patients remaining in the study had serum testosterone levels < or = 50 ng/dL and 97.5% (115/118) had levels < or = 20 ng/dL. At study completion, the mean (SD) serum testosterone level was 6.12 (4.3) ng/dL (range, 3.0-27.0 ng/dL). No breakthrough or acute-on-chronic responses were reported throughout the study. From baseline to month 6, mean (SD) luteinizing hormone level decreased from 8.0 (7.3) mIU/mL to 0.09(0.1) mIU/mL, and mean (SD) prostate-specific antigen level decreased from 32.9 (86.3) ng/mL to 3.2 (12.0) ng/mL. Treatment-related adverse events were reported by 74.2% (89/120) of patients, the most common being hot flashes (56.7%). CONCLUSION: This 6-month, open-label, noncontrolled study showed LA-2500 7.5-mg depot was well tolerated and maintained testosterone suppression (< or = 50 ng/dL) in the patients completing the study without any testosterone breakthrough responses.

A clinical study of 22.5 mg. La-2550: A new subcutaneous depot delivery system for leuprolide acetate for the treatment of prostate cancer.

PURPOSE: The safety, efficacy and pharmacokinetics of a unique 3-month subcutaneous depot of leuprolide acetate were investigated in patients with prostate cancer. MATERIALS AND METHODS: This open label, noncomparative, 6-month multicenter study enrolled 117 patients diagnosed with adenocarcinoma of the prostate. LA-2550 (22.5 mg. depot) (Atrix Laboratories, Fort Collins, Colorado) was administered subcutaneously once every 3 months. The primary efficacy parameter was serum testosterone 50 ng./dl. or less. Pharmacokinetics were analyzed in a subset of 22 patients. RESULTS: Of the 117 enrolled patients 111 (98%) completed the 6-month study. Five patients withdrew for nontreatment related events and 1 was withdrawn because he received less than a full dose of the study drug. By day 28, 98% of patients had serum testosterone 50 ng./dl. or less and 84% had achieved 20 ng./dl. or less. By day 35 all patients had 50 ng./dl. or less testosterone. A patient with a breakthrough response after testosterone suppression on day 49 (112 ng./dl.) regained suppression (27 ng./dl.) 14 days after the second injection (day 98). At study completion all patients had 50 ng./dl. or less testosterone (mean plus or minus standard error of mean 10.1 +/- 0.07) and 104 of the 111 (94%) had 20 ng./dl. or less. From baseline to month 6 mean luteinizing hormone decreased from 9.2 +/- 1.1 to 0.08 +/- 0.01 mIU/ml. and mean prostate specific antigen decreased more than 98%. No flare reactions were observed and patient assessments of bone pain and urinary symptoms were unchanged. The most common treatment related adverse event was hot flashes, which were mild in 57% of cases, moderate in 12% and severe in 0%. CONCLUSIONS: LA-2550 (22.5 mg. depot) produced and maintained safe and effective suppression of serum testosterone to well below the medical castrate level of 50 ng./dl. or less.