A. Tfayli - Head and neck - Guidelines and clinical case presentation (2-3 ca...
LLA 2011 - B. Cheson - Problems of the design and interpretation of very early clinical trials in hemato-oncology
1. Problems of the Design and Interpretation of Very Early Clinical Trials in Hemato-Oncology Bruce D. Cheson, M.D. Georgetown University Hospital Lombardi Comprehensive Cancer Center Chair, CALGB Lymphoma Committee Washington, D.C., USA
2. Earliest Published Clinical Trials Daniel 1:11-20. Health of Hebrews fed a Kosher diet vs Babylonians fed on a state diet Scurvy on the HMS Salisbury: cider vs vinegar vs lemons
3. Phases of Clinical Trials Phase I - determine toxicity Phase II - determine activity Phase III - evaluate efficacy Phase IV - post-marketing
4. The Problem 6500 trials open to accrual in the U.S. (clinicaltrials.gov) 3% of patients go on studies Studies compete for same patients 63% of trials are ever completed
5. Why our trials fail Blame the design Blame the physicians Blame the patients Blame the wealth of new agents Rarely do we blame the science
6. Problems in New Drug Development Slow rate of accrual to clinical trials Lack of good preclinical models Lack of surrogate endpoints False negatives – missing an active agent False positives – waste resources on ineffective agent
7. High False Positive Rate Rely on a single study Unpredictability of intermediate endpoints Get excited by waterfall plots Short follow-up Response duration Toxicity Unplanned subset analyses
24. Lymphoma Cancer Facts Lymphomas represent the 5th most common form of cancer in the US 2011 projected >75,000 new cases in the US alone with ~ 25,000 deaths/yr ~ 60 morphologic/immunologic subtypes Many more by molecular-genetic assessment No two lymphomas are alike and treatments must be selected based on an individual’s tumor characteristics, by personalized medicine
46. Sos-1 PI3-K Ras Grb2 Shc Raf MEK MEKK-1 JNK MKK-7 ERK AKT The Target Interactome Where’s the target? Courtesy of I. Serebriiskii and E. Golemis, Fox Chase Cancer Center
47. Cheson’s Rule “The efficacy of a new drug is directly proportional to its negative impact on clinical research”
48. Victims of Our Own Successes: The Disease Front-line HL Front-line DLBCL Front-line FL Front-line CLL
49. Victims of Our Own Successes: The Drug New drug B is very active in relapsed/refractory disease Rapidly adopted as front-line Problems No drug B naïve pts against which to compare drug C No data on other drugs in B-relapsed pts Results in relapse too good to improve upon Results in front-line too good to improve upon
51. Solutions Drug B +/- drug C in relapsed-refractory pts Takes a randomized trial Long time for answer Drug C in B-refractory pts No data with other agents Risky
55. Progression-free survival(from study registration)Conventional response assessment 1.0 CR/CRu PR 0.8 SD/PD 0.6 Probability of PFS 0.4 0.2 p < 0.0001 0.0 0 6 12 18 24 30 36 42 48 54 60 Time (months) No. of subjects Event Censored Median PFS (months) CR/CRu 89 35% (31) 65% (58) 52 PR 27 44% (12) 56% (15) NR SD/PD 8 88% (7) 13% (1) 7
56. Progression-free survival(from study registration) Post-treatment PET-CT based assessment 1.0 PET negative PET positive 74% 0.8 0.6 Probability of PFS 0.4 32% HR = 3.5 (95% CI 2.0-6.1) p < 0.0001 0.2 0.0 0 6 12 18 24 30 36 42 48 54 60 Time (months) Event Censored Median PFS (months) No. of subjects PET negative 31% (28) 69% (63) NR 91 PET positive 33% (11) 19 33 67% (22)
57. Progression-free survival according to IPS group and PET results after two cycles of ABVD Gallamini, A. et al. J Clin Oncol; 25:3746-3752 2007
58. BEACOPP treatment for 154 PET-2- positive advanced-stage HL patients PET2-neg All pts PET2+ Gallamini A. et al, Br J Haematol, 152:551, 2011
67. Single arm study cannot identify improved PFSEnrichment design Select/randomize relatively homogenous patients
68. . Rosner G L et al. JCO 2002;20:4478-4484 Randomized Discontuation Design
69. A Proposal for New Drug Development in Cancer Small Phase II Trials Molecular Enrichment Molecular Enrichment Repeat
70. I-SPY2 TRIAL* ADAPTIVELY RANDOMIZE Experimental arm 1 Experimental arm 2 Outcome: Complete Response Population of patients Experimental arm 3 Experimental arm 4 Experimental arm 5 Standard therapy *Investigation of Serial Studies to Predict Your Therapeutic Response with Imaging And moLecular Analysis 2
71. Sometimes We Are Misled By Rigid Response Criteria CLL Cheson, et al, Am J Hematol 29:72, 1988 Cheson, et al, Blood 87:4990, 1996 Hallek, Cheson, et al, Blood 111:5446, 2008 AML Cheson, et al, JCO 8:813, 1990 Cheson et al, JCO 21:4642, 2003 MDS Cheson, et al, Blood 96:3671, 2000 Cheson, et a, Blood 108:419, 2006 NHL Cheson, et al, JCO 17:1244, 1999 Cheson, et al, JCO 25:579, 2007 MM – Don’t blame me!
86. Primary Endpoint Major Response 25 CR 17% nPR 20 Percent Major Response 15 P=0.025 9 7% 10 2 5 8 5 0 FC Oblimersen/ FC O’Brien et al, JCO 27:5208, 2009
87. Survival curves by treatment arm with 5 yrs follow-up ITT population CR or PR patients Patients with fludarabine- sensitive disease O'Brien S et al. JCO 2009;27:5208-5212
88. FC +/- Oblimersen in R/R CLL: PFS O'Brien S et al. JCO 2007;25:1114-1120
89. Reasons for FDA Rejection PFS better than OS in relapsed setting PFS secondary endpoint No PFS difference between arms Small benefit outweighed by adverse effects Could not identify pts likely to benefit
91. Challenge to Trigger Paradigm Shift CURE FOR CANCER Paradigm Shift Mind Shift Patients & Advocates Pharma. & Biotech Co. Insurance & Guidelines $$$ Science & Medical Government & Policy Makers
92. Life Cycle of Drug Development Drug Discovery Rebirth Epiphany Clinical Trial Crisis (inactive, toxic) Safety + Efficacy Approval!! Pharmacoptosis (Programmed drug death)