Safety and Efficacy of Recombinant Fusion Protein Linking Coagulation Factor IX with Albumin (rIX-FP) in Previously Untreated Patients with Hemophilia B.

Introduction Recombinant fusion protein linking coagulation factor IX (FIX) with albumin (rIX-FP) has been shown to be an effective, well-tolerated treatment for patients with severe hemophilia B who had previously received factor replacement therapy. This study investigated the safety and efficacy of rIX-FP in previously untreated patients (PUPs). Methods Patients with moderately severe/severe hemophilia B (≤2% FIX) previously untreated with FIX replacement products received rIX-FP (25-75 IU/kg) prophylaxis weekly or on-demand treatment over ≥50 exposure days (EDs). Primary outcomes were the number of patients who developed FIX inhibitors and mean incremental recovery (IR) following a 50 IU/kg dose of rIX-FP. Secondary outcomes included incidence of adverse events (AEs) and annualized bleeding rates (ABRs). Results In total, 12 PUPs with a median age of 0 years (range, 0-11 years) were treated with rIX-FP for a median of 50 EDs (6/12 prophylaxis; 6/12 on-demand then prophylaxis). Overall, 11/12 patients did not develop FIX inhibitors; one 11-year-old patient developed an inhibitor against FIX after 8 EDs and was ultimately withdrawn. Mean (standard deviation) IR was 1.2 (0.4, n = 8) (IU/dL)/(IU/kg). Of the 137 treatment-emergent AEs recorded, five were attributed to rIX-FP. On the prophylaxis regimen, median ABR was 1.0 (range, 0-3.9, n = 12). No thromboembolic events or deaths occurred during the study. Conclusion This study provides data to support the safety and efficacy of rIX-FP in PUPs requiring on-demand or prophylactic treatment for moderately severe/severe hemophilia B, consistent with results in previously treated patients. Overall, 1/12 patients developed an inhibitor against FIX.

IDELVION: A Comprehensive Review of Clinical Trial and Real-World Data.

Hemophilia B is a bleeding disorder caused by a deficiency of coagulation factor IX (FIX). Treatment with FIX replacement products can increase FIX activity levels to minimize or prevent bleeding events. However, frequent dosing with standard-acting FIX products can create a high treatment burden. Long-acting products have been developed to maintain bleed protection with extended dosing intervals. Recombinant factor IX-albumin fusion protein (rIX-FP) is a long-acting product indicated for the treatment and prophylaxis of bleeding events and perioperative management in adult and pediatric patients. This review outlines data from all previously treated patients in the Prophylaxis and On-Demand Treatment using Longer Half-Life rIX-FP (PROLONG-9FP) clinical trial program and summarizes real-world data evaluating the use of rIX-FP in routine clinical practice. In the PROLONG-9FP program, rIX-FP demonstrated effective hemostasis in all patients at dose regimens of up to 21 days in patients aged ≥ 18 years and up to 14 days in patients aged < 12 years. rIX-FP has a favorable pharmacokinetic profile and an excellent safety and tolerability profile. Extended dosing intervals with rIX-FP led to high levels of adherence and reduced consumption compared with other FIX therapies. Data from real-world practice are encouraging and reflect the results of the clinical trials.

Pharmacokinetics and pharmacodynamics of a recombinant fusion protein linking activated coagulation factor VII with human albumin (rVIIa-FP) in patients with congenital FVII deficiency.

Objectives: Recombinant fusion protein linking activated factor VIIa to human albumin (rVIIa-FP) is a therapeutic option designed to prevent and treat bleeding events in patients with congenital FVII deficiency with reduced infusion frequency compared to current FVII treatments. This study characterized the pharmacokinetics (PK) and pharmacodynamics (PD) of rVIIa-FP.Methods: A phase I multicenter, randomized, open-label, parallel-arm, single-dose study (NCT02470871) was conducted in nine patients with severe congenital FVII deficiency. Patients received their routine FVII product (30 IU/kg plasma-derived FVII [pdFVII] or 25 µg/kg recombinant activated FVII (rFVIIa) [eptacog alfa]), and were then randomly assigned to receive 100 or 300 µg/kg of rVIIa-FP. Blood samples for PK and PD assessments were drawn up to 48 hr after administration. FVIIa activity was determined using a one-stage clotting assay. PD parameters were derived from thrombin generation testing, using the Nijmegen hemostasis assay.Results: rVIIa-FP showed improved PK compared to rFVIIa, with 2- to 3-fold longer t1/2 and 4- to 8-fold lower clearance. Analysis of PD data showed a sustained suppression of lag time below 4.5 min (upper limit of healthy people) for rVIIa-FP compared to rFVIIa. AUEC and ECmax were similar across the two dose groups of rVIIa-FP and rFVIIa.Discussion: rVIIa-FP was well tolerated in patients with congenital FVII deficiency, showed a longer half-life and lower clearance compared to rFVIIa, and lag time remaining within healthy ranges for ≥8 hr.Conclusion: These results warrant further investigation into the efficacy of rVIIa-FP to control and prevent bleeding in patients with FVII deficiency.

Assessment of the Effects of Age and Renal Function on Pharmacokinetics of Bazedoxifene in Postmenopausal Women.

Bazedoxifene (BZA), a chemically distinct selective estrogen receptor modulator, has demonstrated efficacy and long-term safety in phase 3 placebo-controlled studies for prevention and treatment of osteoporosis. Here, we assessed the potential effects of age and renal function on BZA pharmacokinetics in healthy postmenopausal women (aged 55-84 years; CLcr, 32-109 mL/min). This was an open-label, single-dose, parallel, nonrandomized inpatient study conducted in healthy postmenopausal women and postmenopausal women with impaired renal function. Each subject received a single oral dose of BZA in a 20-mg tablet. Twenty-six subjects were enrolled: 8 in each of 3 age groups (55-64 years, 65-74 years, ≥75 years) and 2 (aged 71 and 75 years) with mild renal impairment; all subjects received treatment and completed the study. Age-related changes in pharmacokinetics were apparent. Although the correlation was modest (R2 = 0.28), BZA CL/F decreased steadily with age, such that the oldest group (>75 years) had a mean CL/F 60% less than the youngest group (55-64 years). Over the observed range of CLcr, there was a weak positive correlation (R2 = 0.19) between BZA CL/F and CLcr.

A Study of the Potential Interaction Between Bazedoxifene and Atorvastatin in Healthy Postmenopausal Women.

An open-label, 3-period study was conducted in 30 healthy postmenopausal women (mean age, 58.4 years) who received a single oral dose of atorvastatin 20 mg on day 1 (period 1), multiple daily dosing of bazedoxifene 40 mg on days 4-11 (period 2), and coadministration of atorvastatin 20 mg + bazedoxifene 40 mg on day 12 (period 3). Serial blood samples were collected (24 hours after bazedoxifene and 72 hours after atorvastatin) and assayed for bazedoxifene, atorvastatin, and its ortho-hydroxy and para-hydroxy metabolites. Pharmacokinetic parameters were calculated using noncompartmental methods. Bazedoxifene exposure was not altered with coadministration of atorvastatin 20 mg (Cmax and AUCss were within bioequivalence limits). Similarly, atorvastatin and ortho-hydroxyatorvastatin exposure was equivalent with or without coadministration with bazedoxifene. Para-hydroxyatorvastatin concentrations were below the limit of quantitation under both conditions. Cmax for atorvastatin and ortho-hydroxyatorvastatin was 14% and 18% lower, respectively, and Tmax was 20% and 34% longer, respectively, with the combination compared with atorvastatin alone. There were no serious adverse events, and no subjects discontinued the study because of safety. No clinically significant pharmacokinetic interaction was observed between bazedoxifene and atorvastatin or its active metabolites, indicating they may be safely coadministered without dosage adjustment.

Pharmacokinetics and Safety of Bazedoxifene in Hepatically Impaired and Healthy Postmenopausal Women.

Bazedoxifene, a selective estrogen receptor modulator with proestrogenic effects on bone and lipid metabolism and antiestrogenic effects on the breast and endometrium, is a treatment option for osteoporosis in postmenopausal women. It is extensively metabolized by the liver; therefore, a decrease in liver function was expected to decrease bazedoxifene clearance. This single-dose, open-label, inpatient/outpatient, nonrandomized study assessed the pharmacokinetics of bazedoxifene 20 mg in 18 postmenopausal women with hepatic impairment and 18 matched healthy postmenopausal women. Bazedoxifene elimination was slower, and exposure was higher, in hepatically impaired subjects compared with healthy subjects. In subjects with severe (Child-Pugh C) liver impairment, bazedoxifene mean half-life was 50% longer than that of healthy subjects. Area under the concentration-time curve geometric mean ratios (90%CI) for Child-Pugh A, B, and C liver impairment vs healthy subjects were 243% (156-379), 209% (135-326), and 368% (236-572), respectively. Although there were no severe adverse events in this study, bazedoxifene use in patients with hepatic impairment is not recommended.

Pharmacokinetic Drug Interaction Study of Bazedoxifene and Ibuprofen.

The purpose of this article was to evaluate the potential for a pharmacokinetic interaction between bazedoxifene and ibuprofen. In a randomized crossover study, 12 healthy postmenopausal women (aged 45-65 years) received either a single oral dose of ibuprofen (600-mg tablet), bazedoxifene (20-mg capsule), or both ibuprofen and bazedoxifene during the 3 treatment periods. Serial blood samples were collected for pharmacokinetic analyses. There was no relationship between the UGT1A1 genotype and bazedoxifene clearance. The 90% log-transformed confidence intervals (CIs) for bazedoxifene Cmax , 96% to 144%, and AUC, 85% to 134%, were slightly above the bioequivalence limits of 80% to 125%. The 90% log-transformed CIs for ibuprofen pharmacokinetic parameters were within these limits (Cmax , 92%-122%; AUC, 94%-106%). The increase in bazedoxifene plasma concentrations when combined with ibuprofen versus bazedoxifene alone is unlikely to be clinically significant. The lack of interaction between bazedoxifene and ibuprofen suggests that they may be coadministered without dose adjustment.

Pharmacokinetics, Dose Proportionality, and Bioavailability of Bazedoxifene in Healthy Postmenopausal Women.

PURPOSE: Bazedoxifene is a selective estrogen receptor modulator that has estrogen agonist effects on bone and lipid metabolism while having neutral or estrogen antagonist effects on the breast and endometrium. The present report describes findings from 3 Phase I clinical studies that evaluated the single-dose pharmacokinetics (study 1; n = 84), multiple-dose pharmacokinetics (study 2; n = 23), and absolute bioavailability (study 3; n = 18) of bazedoxifene. METHODS: All 3 studies enrolled healthy postmenopausal women who were either naturally postmenopausal or had undergone bilateral oophorectomy at least 6 months before the start of the study. FINDINGS: Study 1 showed that unconjugated and total (unconjugated and conjugated) bazedoxifene levels increased proportionally with ascending oral doses of bazedoxifene (through the dose range of 5-120 mg). Evaluation with or without food intake was conducted at the 10-mg dose, with no clinically relevant effect on pharmacokinetic parameters. Study 2 showed that bazedoxifene achieved steady state in 1 week and exhibited linear pharmacokinetics in doses of 5 to 40 mg with no unexpected accumulation over the dose range. In accordance with a linear pharmacokinetic profile, mean maximum plasma concentration values increased with increasing dose, with values of 1.6, 6.2, and 12.5 ng/mL for the 5-, 20-, and 40-mg doses, respectively. In study 3, tablet and capsule formulations of bazedoxifene formulations had an estimated oral bioavailability of ~6%. The clearance of bazedoxifene was 0.4 (0.1) L/h/kg based on intravenous administration. The oral formulations had comparable exposure profiles with respect to AUC and AUC0-t, and the 90% CIs for these values were within the bioequivalence limits of 80% to 125%. Bazedoxifene was safe and well tolerated in all 3 studies. IMPLICATIONS: These pharmacokinetic evaluations in healthy postmenopausal women found that bazedoxifene displayed linear pharmacokinetics with doses ranging from 5 to 40 mg, with no unexpected accumulation. Food did not seem to have any clinically relevant impact on pharmacokinetic parameters. Bazedoxifene had an estimated oral bioavailability of ~6% and was safe and well tolerated in the range of doses evaluated.

A double-blind, randomized, ascending, multiple-dose study of bazedoxifene in healthy postmenopausal women.

Bazedoxifene is a novel selective estrogen receptor modulator in clinical development for the prevention and treatment of postmenopausal osteoporosis. This phase 1, double-blind, randomized, placebo-controlled study (N = 107) of healthy postmenopausal women examined the pharmacokinetics and safety/tolerability profile of multiple doses of bazedoxifene (1, 2.5, 5, 10, 20, 40, and 80 mg) administered orally once daily for 30 days. Bazedoxifene demonstrated a half-life of 25 to 30 hours, reached steady state within 7 days, and exhibited linear pharmacokinetics over a dose range of 5-80 mg. Fibrinogen levels decreased with bazedoxifene doses of 5 mg and greater; these changes were significant for bazedoxifene 20, 40, and 80 mg (P ≤ .05 vs placebo), but were not dose dependent. Bazedoxifene was associated with increased levels of sex hormone-binding globulin, thyroxine-binding globulin, and cortisol-binding globulin (CBG); only increases in the levels of CBG appeared to be dose related. Bazedoxifene was safe and well tolerated within the tested dose range. Bazedoxifene showed no differences from placebo in adverse event reports, vital sign measurements, or electrocardiogram findings.

Metabolic disposition of [14C]bazedoxifene in healthy postmenopausal women.

Bazedoxifene is a selective estrogen receptor modulator under development for the prevention and treatment of osteoporosis. The disposition of [(14)C]bazedoxifene was determined in six healthy postmenopausal women after administration of a single oral dose of 20 mg (200 microCi). After dosing, blood was collected at frequent intervals, and urine and fecal samples were collected for up to 10 days. Aliquots of plasma, blood, urine, and fecal homogenates were analyzed for concentrations of radioactivity. Bazedoxifene metabolite profiles in plasma and feces were determined by high-performance liquid chromatography with radioactivity flow detection; metabolite structures were confirmed by liquid chromatography-mass spectrometry. Bazedoxifene was rapidly absorbed, exhibiting a mean peak plasma concentration of 3.43 ng/ml at 1.2 h postdose. The total mean recovery of the radioactive dose in excreta was 85.6%, with the majority recovered in feces (84.7%) and only a small fraction (0.81%) in urine. Radiochromatograms of plasma revealed that glucuronidation was the major metabolic pathway; little or no cytochrome P450-mediated metabolism was evident. The majority of circulating radioactivity was constituted by metabolites, with bazedoxifene-5-glucuronide being the predominant metabolite (up to 95%). Bazedoxifene-4'-glucuronide was a minor metabolite (up to 20%), and unchanged bazedoxifene represented 0 to 13% of the radioactivity in most plasma samples. Unchanged bazedoxifene was the major radioactive component in feces, however, reflecting unabsorbed drug and/or glucuronides that were hydrolyzed by intestinal bacterial enzymes. [(14)C]Bazedoxifene was generally well tolerated. These findings demonstrated that, after oral administration in healthy postmenopausal women, bazedoxifene was rapidly absorbed, metabolized via glucuronidation, and excreted predominantly in feces.