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orBec ® (oral beclomethasone dipropionate) NDA 22-062. DOR BioPharma, Inc. Oncologic Drugs Advisory Committee May 9, 2007. 5030.01. Christopher Schaber, Ph.D. President & CEO DOR BioPharma, Inc. 5031.01. Agenda. Introduction orBec ® beclomethasone dipropionate
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orBec®(oral beclomethasone dipropionate)NDA 22-062 DOR BioPharma, Inc. Oncologic Drugs Advisory Committee May 9, 2007 5030.01
Christopher Schaber, Ph.D President & CEO DOR BioPharma, Inc. 5031.01
Agenda • Introduction • orBec® beclomethasone dipropionate • Acute Graft-vs-Host Disease (GVHD) • Rationale for oral BDP • Randomized, placebo-controlled trials of oral BDP • Summary of clinical trial results • Benefit/Risk 5032.01
Presenter George B. McDonald, MD Professor of Medicine, University of Washington Head, Gastroenterology/Hepatology Section, Fred Hutchinson Cancer Research Center Moderator Timothy C. Rodell, MD Medical MonitorDOR BioPharma, Inc. 5158.01
External Advisors 5033.01
DOR BioPharma, Inc. • Focused on treatments for • Life-threatening side effects of cancer treatments • Serious GI diseases • Enteron Pharmaceuticals is a wholly owned subsidiary of DOR BioPharma, Inc. 5034.01
Beclomethasone Dipropionate • Diester of beclomethasone, a potent synthetic corticosteroid • Anti-inflammatory and immunosuppressive effects • Widely used in topical applications • Inhaled • Intranasal • Enema 5035.01
Nomenclature • BDP • Beclomethasone dipropionate • Oral BDP • Formulation • Immediate-release (IR) tablet (1 mg) • Delayed-release, enteric-coated (EC) tablet (1 mg) • Proposed dosing • 1 IR and 1 EC 4 times daily • orBec® • Proposed trade name for oral BDP 5036.01
Development History 5037.01
Basis for Approval Approval is merited based on a favorable safety profile and clinical benefits as measured by reductions in • GVHD treatment failure • Mortality at transplant Day 200 • Mortality 1 year post-randomization 5039.01
Proposed Indication for orBec® (oral BDP) orBec is indicated for the treatment of graft versus host disease (GVHD) involving the gastrointestinal (GI) tract in conjunction with an induction course of high-dose prednisone or prednisolone. 5040.01
George B. McDonald, MD Professor of Medicine, University of Washington Head, Gastroenterology/Hepatology Section, Fred Hutchinson Cancer Research Center 5041.01
Agenda • Introduction • orBec® beclomethasone dipropionate • Acute Graft-vs-Host Disease (GVHD) • Rationale for oral BDP • Randomized, placebo-controlled trials of oral BDP • Summary of clinical trial results • Benefit/Risk 5042.01
Acute GVHD • Inflammatory multi-system disorder • Attack of donor immune cells and release of cytokines in host tissues • Target organs • Gastrointestinal tract • Skin • Liver • Graded I - IV • Affects approximately 60% of allogeneic graft recipients (~ 7000 patients per year in US) 5044.01
Distribution of the Severity of Grade II-IV GVHD1 25% mortality at transplant Day 2002,3 1 Martin et al, BBMT. 2004;10:210-327. 2 Ratanatharathorn V, et al. Blood. 1998;92:2303-2314; 3 Nash R, et al. Blood. 2000;96:2062-2068. 5046.01
Time Line for Hematopoietic Cell Transplantation After a Myeloablative Regimen Methotrexate GVHDprophylaxis Calcineurin inhibitor Donor cells Infections Potential for high-dose prednisone use Conditioning Acute GVHD appearance 0 25 50 75 100 200 365 Transplant Day zero Day post-transplant 5043.01
Time Line for Hematopoietic Cell Transplantation After a Non-Myeloablative Regimen MMF GVHDprophylaxis Calcineurin inhibitor Donor cells Infections Potential for high-dose prednisone use Conditioning Acute GVHD appearance 0 25 50 75 100 200 365 Transplant Day zero Day post-transplant 5528.01
Gastrointestinal Graft-vs-Host Disease Symptoms • Anorexia • Nausea • Vomiting • Diarrhea Antral edema Duodenum Massive edema insmall intestine 5048.01
Gastric and Intestinal GVHD Gastric Intestinal 5049.01
2 mg/kg/day Prednisone Dosing Schedule 2.0 1.6 1.2 Prednisone (mg/kg/day) 0.8 0.4 0 0 7 14 21 28 35 42 49 56 63 70 Days of prednisone treatment 5050.01
1 mg/kg/day Prednisone Dosing Schedule 2.0 1.6 2 mg/kg 1.2 Prednisone (mg/kg/day) 0.8 1 mg/kg 0.4 0 0 7 14 21 28 35 42 49 56 63 70 Days of prednisone treatment 5051.01
Effect of Prednisone at Day 80 After Allogeneic HCT Hakki M, et al. Blood. 2003;102:3060-3067. 5161.01
Infection Risk in Patients Treated With Prednisone for Acute GVHD 1 Nichols WG, et al. Blood. 2001;97:867-874 2 Marr KA, et al. Blood. 2002;100:4358-4366 5054.01
Agenda • Introduction • orBec® beclomethasone dipropionate • Acute Graft-vs-Host Disease (GVHD) • Rationale for oral BDP • Randomized, placebo-controlled trials of oral BDP • Summary of clinical trial results • Benefit/Risk 5055.01
Rationale for Oral BDP • Gastrointestinal involvement predicts the outcome of acute GVHD1 • Prednisone therapy effective but there are many complications from prolonged use • Oral, topically active corticosteroids have been used safely and effectively in other inflammatory GI diseases 1 Hill G and Ferrara J. Blood. 2000;95:2754-2759. 5056.01
Expected Clinical Benefits from Oral BDP BDP maintains GVHD in remission Decreased prednisone exposure Decreased prednisone adverse effects and preservation of immune function Better outcomes 5662.01
Agenda • Introduction • orBec® beclomethasone dipropionate • Acute Graft-vs-Host Disease (GVHD) • Rationale for oral BDP • Randomized, placebo-controlled trials of oral BDP • Summary of clinical trial results • Benefit/Risk 5058.01
Development History 1991 Oral BDP development began (Investigator-Initiated IND) 1991 Development funded by FDA Orphan Drugs Division 1995 Phase 1 trial completed (Study 615) 1998 Phase 2 trial completed (Study 875) 1998 Orphan Indication Designation 1999 Ownership was transferred to Enteron Pharmaceuticals 2000 Fast Track Designation 2005 Pivotal Phase 3 trial completed under Special Protocol Assessment (SPA), Division of Gastrointestinal and Coagulation Drug Products (Study ENT 00-02) 2006 NDA 22-062 submitted September 21, 2006 5037.01
Study 875: Major Eligibility Criteria • Inclusion • Allogeneic hematopoietic cell transplantation • Signs and symptoms of GVHD • Anorexia, nausea, vomiting, or diarrhea • Biopsy-proven GVHD in GI mucosa • Absence of infection at baseline • Exclusion • Severe skin or liver GVHD • Diarrhea > 1 L per day • Systemic corticosteroid use within 30 days 5059.01
Study 875 Screening Phase Treatment Phase Follow-up Phase RANDOMIZATION Prednisone 1 mg/kg/d + oral BDP 2 mg QID Oral BDP 2 mg QID + prednisone 0.125 mg/kg/d SCREENING Follow-up period taper prednisone Prednisone 1 mg/kg/d + placebo QID Placebo + prednisone 0.125 mg/kg/d 10 days 20 days 1:1 Study Day –3 to 0 Study Day 1 to 30 Study Day 31 to 40 Continued GVHD prophylaxis 5060.01
Prednisone Dosing Schedules – 2 mg/kg/day vs 1 mg/kg/day vs Study 875 2.0 1.6 2 mg/kg 1.2 Prednisone (mg/kg/day) 0.8 1 mg/kg 0.4 Study875 0 0 7 14 21 28 35 42 49 56 63 70 Days of prednisone treatment 5057.01
Study 875: Endpoints • Primary • GVHD treatment failure through Study Day 30 • Eating < 70% of caloric requirements, or • Requiring additional immunosuppressive drugs for GVHD • Secondary • GVHD treatment failure through Study Day 40 • Safety • Adverse events related to study drug • Infectious complications 5061.01
Study 875: Primary Efficacy GVHD Treatment Failure by Day 30 (ITT) p=0.021 (c2test) n=29 n=31 5064.01
Study 875: Time to GVHD Treatment Failure through Study Day 30 (Full Analysis Set) 1.00 p=0.033 0.75 Placebo 0.50 Probability BDP 0.25 0 0 5 10 15 20 25 30 35 Days since randomization 1-10 11-20 21-30 BDP 9/31 0/22 0/22 Placebo 13/29 1/16 3/15 (# events/# at risk) 5666.01
Study 875: Secondary Efficacy GVHD Treatment Failure by Day 40 (ITT) p=0.005 (c2test) n=29 n=31 5065.01
Study 875: Conclusions • Oral BDP significantly lowered treatment failure rates at the end of the 30-day treatment and 10-day follow-up • Greater proportion of patients able to eat ≥ 70% of their caloric requirements • No significant safety issues • No difference in frequency of infections • Proof of concept for design of pivotal trial (ENT 00-02) 5066.01
Study ENT 00-02: Design Considerations • Similar inclusion/exclusion criteria to Study 875 • Caloric intake not a feasible endpoint for multi-center trial • Longer treatment period might improve efficacy • 50-day treatment period (Study Day 50) • Demonstrate durability of treatment effect • 30 days after study drug discontinuation (Study Day 80) • Transplant Day-200 survival as a safety endpoint • Reviewed with FDA Division of Gastrointestinal and Coagulation Drug Products 5163.01
Study ENT 00-02 Screening Phase Treatment Phase Follow-up Phase RANDOMIZATION Prednisone 1 mg/kg/d + oral BDP 2 mg QID Oral BDP 2 mg QID + prednisone 0.0625 mg/kg/d SCREENING Follow-up period taper prednisone Prednisone 1 mg/kg/d + placebo QID Placebo + prednisone 0.0625 mg/kg/d 10 days 40 days 1:1 Study Day –3 to 0 Study Day 1 to 50 Study Day 51 to 80 Continued GVHD prophylaxis 5067.01
Study ENT 00-02: Endpoints • Primary • Time to GVHD treatment failure through Study Day 50 • Unresponsive or recurrent GVHD requiring additional immunosuppressive drugs • Secondary • GVHD treatment failure rates at Study Days 10, 30, 50, 60, and 80 • Karnofsky performance score • Exposure to systemic corticosteroids • Safety • Survival at 200 days post-transplant • Treatment-emergent adverse events • Laboratory values 5068.01
Study ENT 00-02: Design • Planned sample size and power • 130 subjects (65 per group) • 49 GVHD treatment failures required • 80% power to detect ≥55% reduction (HR=0.45) in risk of GVHD treatment failure during 50-day protocol treatment period • 5% significance level, 2-sided • Log-rank test • Randomization stratified • Study center • Donor type (HLA-matched sibling vs others) • Use of topical corticosteroids at baseline (Yes/No) 5069.01
Study ENT 00-02: Statistical Analysis Plan • Original plan amended prior to database lock • Primary analysis would be stratified by donor type only • Primary analysis for time-to-event endpoints • Kaplan-Meier method • Stratified log-rank test • 5% significance level, 2-sided 5164.01
Study ENT 00-02: Statistical Issues • Overall false-positive error rate spent on primary endpoint (p=0.118) • No adjustment to the significance levels were specified in the analysis plan to control for inflation of the overall false-positive error rate due to multiple testing • Retrospective adjustment of significance levels for analysis of secondary endpoints is considered not meaningful once the results are known • Given the clinical importance of the secondary endpoints and post-hoc survival analyses, we are reporting these results to aid review. These inferential results have not been adjusted for multiplicity. 5070.01
Higher AML > CR1 ALL CML/BC or AP Hodgkin’s disease Lymphoma Myeloma APL Renal cell carcinoma Plasmacytic leukemia Biphenotypic leukemia Lower CLL CML/CP CMML AML/CR1 MDS Myelofibrosis Myeloproliferative syndrome P. vera Aplastic anemia Study ENT 00-02: Definition of High vs Low Relapse Risk 5072.01
Study ENT 00-02Primary Efficacy Endpoint (Time to GVHD Treatment Failure through Study Day 50 - ITT) • GVHD treatment failures Placebo n=30 BDP n=18 • K-M estimates at Study Day 50 Placebo 48% (0.39, 0.60) BDP 31% (0.23, 0.43) • Hazard Ratio (95% CI) 0.63 (0.35, 1.13) • Stratified log-rank test p=0.118 • Interaction test p=0.907
Study ENT 00-02Primary Efficacy Endpoint (Time to GVHD Treatment Failure through Study Day 50 - ITT) 1.00 0.75 Probability Placebo 0.50 0.25 BDP 0 0 10 20 30 40 50 Days since randomization 1-10 11-20 21-30 31-40 41-50 BDP 8/62 3/50 4/47 2/42 1/39 Placebo 4/67 8/61 9/50 4/41 5/36 5078.01 (#events/#at risk)
Study ENT 00-02Secondary Efficacy Endpoint (Time to GVHD Treatment Failure through Study Day 80 - ITT) • GVHD treatment failures Placebo n=39 BDP n=22 • K-M estimates at Study Day 80 Placebo 65% (0.55, 0.76) BDP 39% (0.30, 0.52) • Hazard Ratio (95% CI) 0.54 (0.32, 0.93) • Stratified log-rank test p=0.023 • Interaction test p=0.713
Study ENT 00-02Secondary Efficacy Endpoint (Time to GVHD Treatment Failure through Study Day 80 - ITT) 1.00 Treatment period Follow-up period 0.75 Placebo Probability 0.50 BDP 0.25 0 0 10 20 30 40 50 60 70 80 90 Days since randomization 1-10 11-20 21-30 31-40 41-50 51-60 61-70 71-80 BDP 8/62 3/50 4/47 2/42 1/39 1/37 2/35 1/30 Placebo 4/67 8/61 9/50 4/41 5/36 1/30 4/29 4/23 5303.01 (#events/#at risk)