Open-Label Crossover Oral Bioequivalence Pharmacokinetics Comparison for a 3-Day Loading Dose Regimen and 15-Day Steady-State Administration of SUBA-Itraconazole and Conventional Itraconazole Capsules in Healthy Adults

ABSTRACT Super bioavailability (SUBA) itraconazole (S-ITZ), which releases drug in the duodenum, and conventional itraconazole (C-ITZ), which releases drug in the stomach, were compared in two pharmacokinetic (PK) studies: a 3-day loading dose study and a 15-day steady-state administration study. These were crossover oral bioequivalence studies performed under fed conditions in healthy adult volunteers. In the loading dose study, C-ITZ (two doses of 100 mg each) and S-ITZ (two doses of 65 mg each) were administered three times daily for 3 days and once on day 4 (n = 15). For the steady-state administration study, C-ITZ (two doses of 100 mg each) and S-ITZ (two doses of 65 mg each) were administered twice daily for 14 days and a last dose was administered 30 min after a meal on day 15 (n = 16). Blood samples collected throughout both studies were analyzed for ITZ and hydroxy-ITZ (OH-ITZ) levels. Least-squares geometric means were used to compare the maximum peak concentration of drug after administration at steady state prior to administration of the subsequent dose (Cmax_ss), the minimum drug level after administration prior to the subsequent dose (Ctrough), and the area under the curve over the dosing interval (AUCtau) of each formulation. The ratios of itraconazole (ITZ) and OH-ITZ for S-ITZ to C-ITZ were between 107% and 118% in both studies for Cmax_ss, Ctrough, and AUCtau, which were within the U.S. FDA-required bioequivalence range of 80% to 125%. At the end of the steady-state administration study, 13 of 16 volunteers obtained higher mean ITZ blood Ctrough levels of >1,000 ng/ml when they were administered S-ITZ (81%) than when they were administered C-ITZ (44%). The study drugs were well tolerated in both studies, with similar adverse events (AEs). All treatment-emergent AEs resolved after study completion. One volunteer receiving C-ITZ discontinued due to a treatment-unrelated AE in the steady-state administration study. No serious AEs were reported. Total, trough, and peak ITZ and OH-ITZ exposures were similar between the two formulations. Therefore, SUBA-ITZ, which has 35% less drug than C-ITZ, was bioequivalent to C-ITZ in healthy adult volunteers and exhibited a safety profile similar to that of C-ITZ.

Melphalan and Dexamethasone Plus Bortezomib Induces Hematologic and Organ Responses in AL-Amyloidosis with Tolerable Neurotoxicity.

Abstract 746 Introduction: Primary systemic amyloidosis (AL) is a monoclonal plasma cell disorder associated with progressive organ dysfunction and short survival. Standard therapy for patients (pts) not eligible for autologous stem cell transplant (ASCT) is melphalan (Mel; M) + dexamethasone (Dex; D). With non-ASCT therapy, the median overall survival (OS) of high-risk AL pts remains < 1 yr. After the VISTA study showed the addition of bortezomib (Bz) to Mel + Prednisone improved response rate, complete response rate, response duration, and OS in pts with myeloma, we designed this study to determine if adding Bz to MD improves outcomes in AL. Key eligibility criteria: ECOG PS ≤ 3, Cr ≤ 5 mg/dL, T.Bili ≤ 2.5 x IULN, ALT/AST ≤ 3 x IULN, ANC ≥ 1.0 K/mm3, PLT ≥ 80 K/mm3, peripheral neuropathy (PN) ≤ Gr 2 (≤ 1 if painful), no lower limit for LVEF. Study design: Two-stage Phase II study. Stage I: 16 pts with biopsy-proven AL or light chain deposition disease (LCDD). 1° endpoint: complete hematologic responses (cHR). If ≥5 cHRs observed, then 2nd stage with 17 more pts to be opened. The study has a 90% power to detect a true cHR rate of 50%. 2° endpoints include overall HR (cHR + Partial Responses (PR)), organ response (OrR), and OS. Treatment: M (9 mg/m2 PO days 1-4; 6 mg/m2 if Cr > 2.5 mg/dL), Bz (1.3 mg/m2 IV days 1, 8, 15, 22; 1.0 mg/m2 if pt has PN at baseline) and D (40 mg PO/IV days of & days after Bz; 20 mg if ≥ 70 yrs, peripheral edema, or CHF) in 4-6 wk cycles, max of 20 cycles. PN was assessed serially with the FACT/GOG-Ntx survey. Results: To date, 23 pts have been enrolled: 21 with AL; 2 with LCDD. Med age 64 (range: 47-76). Med # prior Rx: 1 (range: 0-2; 7 with ≥1 prior ASCT). Med # organs involved: 4 (range 1-6; 8 pts with ≥ 3). PS 0-1/2-3: 18/1. Response data for the 16 pts comprising stage 1 of this two-stage study are reported here; accrual of all 33 pts is expected to be complete by ASH, and results will be updated. One pt who was not response-evaluable (RE) for HR is included in toxicity data (n=17). Med # cycles MD-Bz: 4+ (range: 2-12+; 9 pts still on treatment). 15 of 16 pts had heme responses: 6 cHRs & 9 PRs. Ten RE pts had OrR (2 cardiac, 3 renal, 6 nerve, 1 lung; total >10 because some pts improved in > 1 organ). Nerve symptom improvement occurred exclusively in pts with cHR. Two pts had progressive disease (PD). Two pts died (4.5 and 9 mos from enrollment, from pneumonia and PD, respectively). Despite baseline dose adjustment for co-morbidities, 12 pts needed subsequent dose-reduction of ≥ 1 of the study meds during therapy (10 Bz, for thrombocytopenia and/or PN in almost all cases). Five pts developed neutropenia (Gr 3-4: 1), 15 pts developed thrombocytopenia (Gr 3-4: 11). Nine pts developed peripheral neuropathy (Gr 3: 2). Other grade 3-4 non-hematologic AEs seen in ≥ 2 pts included edema (5), syncope (3), SVT (2), dehydration (2), fatigue (2), and renal failure (2). One pt developed reversible cardiomyopathy (cycle 8) attributed to Bz. Calculated sensory/dysfunction (S/D) composite scores based on patient responses from the FACT/GOG-Ntx survey improved in 7 of 14 pts between cycles 1 and 4, were stable in 4 pts and worsened in only 3. On average, the S/D score accounted for 43% of each pt's total Ntx score at baseline, whereas it only accounted for 39% of the score after 4 cycles, and 45% after 8 cycles, indicating progressive disability from Bz-related PN was uncommon. As results of nerve conduction studies did not correlate well with reported symptoms or FACT/GOG-Ntx scores in stage 1 of the study, mandatory EMGs were discontinued in stage 2. Conclusions: MD-Bz shows promising activity in the treatment of AL, with 94% of pts in the first stage of this trial achieving HR (38% cHR) and evidence of OrR observed in 63%. Toxicity is manageable, but meds often require baseline or subsequent dose adjustment. A randomized study of MD +/- Bz in AL is planned. Disclosures: Zonder: Cephalon: Consultancy; Pfizer: Consultancy; Amgen: Consultancy; Millennium: Consultancy, Research Funding, Speaking CME Only, No PromotionalTalks; Celgene: Speaking CME only; no Promotional Talks. Off Label Use: Bortezomib is being used in the treatment of AL amyloidosis in this trial; it is currently approved for use as treatment of multiple myeloma.. Matous:Celgene: Honoraria, Speakers Bureau; Cephalon: Speakers Bureau. Janakiraman:Millennium: Honoraria, Research Funding. Mapara:Resolyx: Membership on an entity's Board of Directors or advisory committees, Research Funding; Cephalon: Membership on an entity's Board of Directors or advisory committees, My Wife: Suzanne Lentzsch, Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees, My wife: Suzanne Lentzsch, Research Funding; Sentium: Stocks. Gasparetto:Millennium: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees.

Efficacy and Safety of Deferasirox (Exjade®) in Patients with Transfusion- Dependent Anemias: Preliminary Results From the First, Retrospective, Multicenter Brazilian Study.

Abstract 5096 Background Deferasirox is a once-daily oral iron chelator with established dose-dependent efficacy for treating transfusional iron overload. The retrospective multicenter Brazilian trial included patients (pts) from 14 sites of 10 states with a variety of transfusion-dependent anemias and was designed to evaluate the efficacy and safety of fixed starting doses of deferasirox based on transfusion history, with subsequent dose titration based on serum ferritin (SF) trends. Data were available from 105 eligible pts at 6 months of treatment and 73 pts from 1-year follow-up period. Methods Pts (aged ≥ 2 yrs) had transfusion-dependent anemia with a history of multiple transfusions (>20 transfusions) and/or SF levels ≥ 1000 ng/mL and serum creatinine level < the upper limit of normal (ULN). Deferasirox starting dose was 10-30mg/kg/day depending on transfusion requirements and subsequent dose adjustments of 5-10 mg/Kg/day (range 0–35 mg/kg/d) were done every 3 months based on changes in SF and safety parameters. Efficacy was assessed monthly by measuring change from baseline in SF levels. Safety was evaluated on a monthly basis according to the incidence and type of adverse events and measurement of laboratory parameters, including serum creatinine and liver enzyme levels. Results 105 pts (40 M, 65 F; mean age 25.0±16.6 yrs) were enrolled; 46% (n=48) aged <20 yrs; 54% Afro-descendant (n=57). Underlying anemias were: sickle cell disease (n=59), β-thalassemia (n=32), myelodysplastic syndromes (n=6) and other conditions associated with anemia (n=8). Most pts (79%, n=83) had received > 40 units of red blood cell (RBC); 71.5% (n=75) were on regular RBC transfusion, 56% of the pts required < 2 RBC units/month and 44% between 2 and 4 RBC units/month. Only 63% (n=66) had received prior chelation therapy: deferoxamine (DFO; 51.4%) or DFO/deferiprone combination (11.4%). Sixty-four (61%) pts started on 20 mg/kg/d and 41(39%) > 20-30 mg/kg/d, 15.2% of pts had dose increases at a median of 24 weeks after treatment initiation. Mean ± SD SF levels (μg/L) did significantly reduce at 6 months and 12 months compared to baseline (BL) [from 3132.14 ± 2237.47 to 2784.25 ± 1969.7 at 6 months (p=0.0001) and 2327.46 ± 1873.8 at 12 months (p=0.005)]. The proportion of patients with SF levels < 2000, 2000-3000 and > 3000 μg/L from BL to 6 and 12 months by percentage of patients changed from 36% to 47.5% and 52%; from 26% to 26.5% and 24.5%; from 38% to 26% and 23%, respectively. No patient discontinued the treatment. No death was reported by the investigators during the study. The most common drug-related (investigator-assessed) AEs were mild, transient diarrhea (n=15; 14.3%), rash (n=5; 4.7%), nausea (n=9; 8.5%) and headache (n=6; 5.7%). Seven pts (6.6%) had serum creatinine value >33% above BL on two consecutive visits, 3 (2.8%) of whom had creatinine increases above the ULN; there were no progressive increases or renal failure. Eleven (10.5%) pts had an increase in alanine aminotransferase < 5x ULN but no one experience increases ≥ 5x ULN; levels were already elevated in all of them. Conclusions This first multicenter Brazilian study confirms deferasirox efficacy in achieving a reduction of iron load across a wide range of pts with transfusion-related iron overload. It also supports the clinical approach to fixed starting dose of deferasirox based on iron intake from ongoing blood transfusions and current iron burden with subsequent individual dose titration every 3 months according to SF trends and safety markers. Deferasirox was generally well tolerated in pediatric and adult pts with a safety profile consistent with data from previous clinical trials. The availability of deferasirox as a once-daily oral iron chelator would potentially facilitate improved compliance, and thereby reduce morbidity and mortality from iron overload. Disclosures No relevant conflicts of interest to declare.

Impact of Dose Adjustments on Serum Ferritin (SF) Levels during Long-Term Treatment with Once-Daily, Oral Deferasirox (Exjade®, ICL670).

Background: In deferasirox 1-yr core trials, doses were initially assigned according to baseline liver iron concentration. However, these trials demonstrated that transfusional iron intake has a profound impact on the outcome of chelation therapy and should therefore be considered when assigning deferasirox dose. A large number of patients (pts) were initially assigned 5 and 10 mg/kg/d doses, which were insufficient to balance iron intake from ongoing transfusions. Generally, deferasirox 20/30 mg/kg/d effectively maintained/reduced body iron. This analysis from the 4-yr extension trials evaluates the impact on serum ferritin (SF) of subsequent dose increases in pts who initially received 5/10 mg/kg/d, and the long-term effects of 20 and 30 mg/kg/d doses. Methods: Data for this analysis were pooled from 4 extension trials (106–109E). In the extensions, deferasirox doses were modified based on efficacy and safety markers, including iron burden and transfusional iron intake. SF was measured monthly. Results: In total, 227 pts initially received deferasirox 5 or 10 mg/kg/d, while 182 and 243 received 20 and 30 mg/kg/d, respectively. Underlying diseases included β-thalassemia (n=421), sickle cell disease (n=132), MDS (n=47) and other anemias (n=52). To date, pts have been receiving treatment for a median 3.4 (range: 0–4.5) yrs. Overall, median SF was maintained in the 20 mg/kg/d cohort (Table). In the 30 mg/kg/d cohort, SF levels decreased overall from baseline to month 42 (3734 ng/mL to 2025 ng/mL). However, levels plateaued at around 24 mos in this cohort, reflecting a decrease in mean dose to around 25 mg/kg/d. Median baseline SF in the 5/10 mg/kg/d dose group was 2051 ng/mL, which steadily increased during the first 18 mos of treatment. Subsequent dose increases during the extension phase generally resulted in decreased SF levels, which returned to baseline and below during the remainder of the study. Conclusions: In regularly transfused pts who initially received deferasirox 5/10 mg/kg/d in the core 1-yr clinical trials, SF steadily decreased below baseline once doses were increased to an appropriate level in the extensions. This highlights the importance of ensuring that pts receive the correct deferasirox dose to achieve the goal of therapy, based on iron burden and transfusional iron intake. If a pt is not achieving their therapeutic goal based on SF trends, deferasirox dose should be increased in steps of 5 or 10 mg/kg/d. This analysis confirms that deferasirox 30 mg/kg/d effectively reduces body iron, whereas doses of 20–25 mg/kg/d are generally effective in maintaining iron levels. Median change from baseline in SF (ng/mL) during deferasirox treatment of up to 3.4 years Initial dose, mg/kg/d 5/10 (n=227*) 20 (n=182*) 30 (n=243*) Month Mean dose ± SD† Change in SF (ng/mL) Mean dose ± SD† Change in SF (ng/mL) Mean dose ± SD† Change in SF (ng/mL) *Baseline; †At time point Baseline 2051 2375 3734 1 9.4 ± 1.7 90 19.5 ± 2.6 30 29.2 ± 4.3 −212 6 10.3 ± 3.9 399 18.9 ± 3.5 −15 28.2 ± 5.7 −532 12 13.0 ± 5.4 613 19.0 ± 4.0 −118 26.8 ± 6.6 −716 18 18.5 ± 6.7 831 18.2 ± 7.7 174 23.1 ± 8.6 −676 24 21.7 ± 6.6 635 21.5 ± 6.5 −125 24.5 ± 7.6 −901 30 22.6 ± 7.0 317 22.0 ± 8.5 −205 24.4 ± 8.0 −959 36 21.1 ± 8.7 −211 22.8 ± 7.7 −159 24.3 ± 8.5 −1002 42 21.8 ± 9.3 −65 23.2 ± 8.2 −204 25.8 ± 9.8 −955 EOS 1345 1667 2025

Discontinuation and dose modification of imatinib in clinical practice

7045 Background: Imatinib mesylate induces response in most patients with chronic myelogenous leukemia (CML). Although recent evidence shows benefit from a starting dose of 800mg/day, the recommended starting dose is 400 mg/day for chronic phase patients and 600 mg/day for accelerated phase/blast crisis patients. This study describes trends in imatinib dosing and reasons for dose changes in CML patients. Methods: Using medical and pharmacy claims in the HealthCore Managed Care Database, we identified all patients with CML from 1/1/00–3/31/04. Chart review supplemented claims and confirmed CML diagnosis, obtained phase, treatment, and clinical outcomes through 3/31/05. Results: Among 216 patients receiving imatinib, 87% were diagnosed in chronic phase, 5% in accelerated phase, 1% in blast phase; 7% were unable to be determined. Among 156 patients (72%) with a starting imatinib dose of 400mg/day, 21% had a subsequent dose reduction of at least 100mg/day. The most common reasons for dose reduction were neutropenia, anemia, and nausea/vomiting. Among 29 patients (13%) with a starting dose of at least 600mg/day, 59% had a subsequent dose reduction; the most common reasons for dose reduction in these patients were thrombocytopenia and gastrointestinal bleeding. Among 9 patients (4%) with a starting imatinib dose of at least 800mg/day, 67% had a subsequent dose reduction; the most common reason for dose reduction was myelosuppression. Imatinib therapy was suspended in sixty-two patients (29%), most often because of anemia (11%) or thrombocytopenia (11%); 46 patients (74%) restarted imatinib therapy following a median time of 21 days and the remaining 16 (26%) patients were permanently discontinued. Of the 64 patients (30%) who experienced a dose escalation of at least 100mg/day over starting dose, 34% patients had a subsequent dose decrease; the most common reason for dose reduction among these patients was neutropenia (18%). Conclusions: Among CML patients treated with imatinib, discontinuation and dose changes occurred frequently; the most common reason was myelosuppression. More than 50% of patients starting at higher doses required dose reductions and 1/3 of those receiving dose escalations did not remain on higher doses. No significant financial relationships to disclose.