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Drug Development : Basic Overview of Clinical Trials : Phase I-III. Patricia Mucci LoRusso, D.O. Associate Center Director – Innovative Medicine Yale Cancer Center. <3% of all Cancer Patients Enroll in Clinical Trials. ~1.3% of African Americans Enroll in Clinical Trials.
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Drug Development : Basic Overview of Clinical Trials: Phase I-III Patricia MucciLoRusso, D.O. Associate Center Director – Innovative Medicine Yale Cancer Center
<3% of all Cancer Patients Enroll in Clinical Trials ~1.3% of African Americans Enroll in Clinical Trials Women are Underrepresented
Aggregate Patient Recruitment Success Rates How do patients learn about trials? – CISCRP Tufts CSDD; N=3,534 Phase II-IV protocols
*Cutting Edge Information, “Clinical Operations Benchmarking Per-Patient Costs, Staffing and Adaptive Design” 2011
Non-performing Sites By Therapeutic Area “Addressing Ever-Rising Cost in Conducting Clinical Trials” Covance Inc. 2015
One Large Scale Oncology Trial “Addressing Ever-Rising Cost in Conducting Clinical Trials” Covance Inc. 2015
Non-Performing Sites “Addressing Ever-Rising Cost in Conducting Clinical Trials” Covance Inc. 2015 Average $50k start-up cost Result in budget overrun Many never enroll a single patient or very few Selection of sites often carried out in a non-scientific, non-systematic way Causes delay, impacting trial schedule $334.70 million wasted on non-performing oncology sites from 2006-2011
Potential Accrual Barriers – Patient Level Awareness of trials as an option Understanding of what trial participation involves Concerns around side effects Education about particular trial phase Education about particular treatment Fear of distrust (guinea pig) instead of trust in physician recommendations History of discrimination in medical research Inconvenience of trial logistics: travel, times, number of visits Financial burden
Barriers to Enrollment – Physician Factors • Concerns about potential toxicity from study treatment • Concerns about comorbid conditions of patients • Lack of awareness of accessible clinical trials • Lack of access to clinical trials • Lack of manpower necessary in clinic • Physicians’ own perceptions about the relevance of the questions being addressed in the available trials • Lack of time in busy practices to discuss trial options
Potential Accrual Barriers – Provider Level • Payment metrics at respective practice • Time & resources required to discussing trials • Fear of “losing” patients if refer to clinical trials • Concerns around trial suitability for patient (eg tolerability, benefit) • Belief patient should not be offered trial (not adherent, competent) • Comfort with, and style of, communicating trial to patients
Barriers to Enrollment • Lack of encouragement or support from the attending physician • Unaware of appropriate open trials • Lack time to discuss options at length • Concerned about lack of control over their patient • Unrealistic, inconvenient protocol requirements • Unrealistically restrictive inclusion/exclusion criteria • The most motivated patients are most likely to be excluded • Rejected patients often don’t try again
Barriers to Enrollment (cont.) • Politics • Rivalry between physicians and/or hospital administrators • Bad publicity • Trials conducted unethically garner the most press • Physician or hospital concerns about potential liability • Insurance or HMO policies that may preclude reimbursement for care or make it difficult • HIPAA restrictions • Standardized order sets for “quality”
Logistics Factors • Physicians – lack of support and infrastructure (trial nurses, study coordinators, pharmacy capability, etc) to enable enrollment of patients into trials • Reimbursement of costs incurred by patients during participation in clinical trials (e.g. parking) • Added time off work for patient +/o caregiver • Child support • Patient – lack of social support to attend doctor visits (e.g. for study treatment, management of treatment-related adverse events) • Language barrier
Trial Factors • Dissemination of up-to-date knowledge of available and ongoing trials and how to access them • Paucity of trials for specific patient populations e.g. hepatic/renal dysfunction, elderly • Changing landscape in clinical trial designs e.g. histologic and/or molecular selection including rare subsets • Need for innovative and attractive clinical trials that efficiently evaluate novel agents • Burden of research investigations and visits in clinical trials
Potential Accrual Barriers – Site Level Staffing (research nursing & support staff) Redundant review processes Slow trial activation CRO relationships & issues Lack of standard processes for patient screening Lack of effective clinical trials tools
Potential Accrual Barriers – Systems Levels Massett, et al., Clin Can Res, November 2016 Overly optimistic accrual goals and/or limited accrual feasibility assessment prior to activation Inadequate recruitment planning during trial development process Limited funding & incentives for site & provider involvement (to conduct & offer trials) Trial availability & eligibility for incident patients (eg exclusion for comorbidities, prior # treatments)
Clinical Trials • Clinical trial: a prospectively planned experiment for the purpose of evaluating potentially beneficial therapies or treatments • In general, these studies are conducted under as many controlled conditions as possible so that they provide definitive answers to pre-determined, well-defined questions
Why Clinical Trials? Most definitive method to ultimately determine treatment effectiveness • Other designs more potential biases • One cannot determine in uncontrolled setting whether intervention has made a difference in outcome • Correlation versus causation
Why Clinical Trials? • Help determine incidence of side effects and complications • Theory not always bestpath • May not actually prove itself in reality • May not be tolerable/ feasible solution
Primary vs. Secondary vs Exploratory Objectives • Primary • most important (i.e., central question) • ideally, only one • stated in advance • basis for design / sample size calculations/biostats focus • Secondary • related to primary • also stated in advance • limited number but usually more than one/biostats input • Exploratory • Typically not driven by biostats • eg looking at a biomarker
Elements of Clinical Protocols • Objectives – Primary and Secondary • Biostatistics • Patient selection criteria – Inclusion/Exclusion • Therapeutic Intervention • Dose and Schedule and Mechanism/Route of Delivery • Clinical Work-up and Follow-up Assessment • Toxicity • Toxicity criteria • Dose modifications • Efficacy • Clinical, pharmacodynamic (PD) and QOL • Analysis and interpretation • Primary & secondary endpoints • Correlative studies
Questions to be Answered in Clinical Trials • Why? • Who? • What? • Which? • Where? • When? • How (bad)? • So what?
Why: Define Trial Objectives • Why are you doing this study? • “The primary objective of this trial is …” • Limit number of objectives • Too many will limit trial success • Well planned & thought out objectives • Biostatistics important here • Critical outcome for study a “go/no go” decisions? • Define and use secondary endpoints to generate hypotheses to be explored in future research
Why: Define Trial Objectives • Remember laboratory correlative objectives • “translational research” • Make sure assay and tissue available • Confirm reproducibility and relevance • Make sure tissue/specimens handled appropriately to conduct investigation • Design must take this into account when answering this question!
Who: Patient Selection • Who should enter the trial? • One of the most critical factors affecting study outcome • Each selection criterion should be based on a sound scientific, medical, ethical rationale • Do not copy/paste from other trials! • Inclusion/exclusion should be study directed • Disease type • Prior treatment • Age, sex, organ function and other variables • Measurability and disease status Proper patient selection is key for successful completion and scientific impact of your study!
What: Trial Intervention • What treatment? • What dose and schedule? • Which dose or schedule variations are planned? • How long may the treatment last? • What are specific steps in drug administration? • What should be done to prepare, treat, and monitor the patient prior/during/after treatment? • Will the same treatment be given to all patients? • If not, what are the differing procedures? • What are the methods to assess compliance with the procedures defined in your protocol?
Which: Assessment of Critical Endpoints WHICH: • Methodology is used to select patients (Performance status? Pain score? NYHA?...) • Standard will be used to assess response? • Instrument for evaluation of safety and toxicity • Methodology to be applied for the statistical, correlative and translational endpoints?
Where: Tumor and Response Assessment • Where are primary tumor lesions to be measured? • What happened to it during treatment? • Location, size, density • Criteria for response: RECIST vs. iRECIST vs WHO • Pre-baseline assessment of progression required? • Target vs. non-target lesions • Other parameters of effect being studied adequately? • TTP, TTF, OS, duration of response, etc. • Immune response • Target modulation in tumor tissue or surrogate • Functional imaging
When: Timing of Assessment • When will assessments of primary, secondary and translational endpoints be performed? • Do we truly know timing for translational endpoints? • Is the timing of assessments compatible with the chosen endpoints? • Will dose delays or modifications affect the schedule of reassessment? • Will there be a sufficient number of patients to obtain adequate information? • Is the chosen timing compatible with the routines of physicians, nursing staff, hospital and patient?
How (bad): Safety and Toxicity • To what degree does treatment interfere with patient well-being? • How assessed (CTCAE? QoL? Self-made instrument?) • What modifications are incorporated to avoid or minimize the risk or severity of toxicity? • Dose reduction • Dose delay • Dose omission • Supportive care (prophylaxis, intervention, secondary prevention) • Discontinuation of individual treatment? • Termination from the study (specify criteria!)
So What: Analysis and Interpretation • Has study design been followed, is the trial “mature”? • Evaluate the compliance of all involved parties • What do the results and observations mean? • Primary endpoint reflects the hypothesis tested • Secondary endpoints reflect hypotheses generated • Have the appropriate statistical tools been used? • Beware of sporadic “significant” results that result from multiple, unplanned comparisons • Beware of retrospective subgroup analyses Given the results, how should we move forward (go/no go; generate confirmatory evidence in laboratory models; additional clinical trials…)?
Definitions • Single Blind Study: A clinical trial where the participant does not know the identity of the treatment received • Double Blind Study: A clinical trial in which neither the patient nor the treating investigators know the identity of the treatment being administered.
Definitions • Placebo: • Used as a control treatment 1. An inert substance made up to physically resemble a treatment being investigated 2. Best standard of care if “placebo” unethical 3. “Sham control” 4. Used in Randomized trials
Definitions • Adverse event: • An incident in which harm resulted to a person receiving health care. • Examples: Death, damage to liver, nausea, drop in white cells or platelets • Not always easy to specify in advance because many variables will be measured • May be known adverse effects from earlier trials or preclinical toxicology studies • Animals and man different – can’t always predefine • Not necessarily linked to assigned treatment • Important to decipher if drug effect
Adverse Events (AEs) • Challenges • Long term follow-up versus early benefit • Rare AEs may be seen only with very large numbers of exposed patients and/or long term follow-up • Example – COX II inhibitors • Vioxx & Celebrex • Immediate pain reduction versus longer term increase in cardiovascular risk
Phase I Trial • Primary Objective : Determine an acceptable range of dose(s) & schedule(s) for a new drug • Determine toxicities (dose-limiting and others) • Secondary Objectives: Pharmacokinetics, Pharmacodynamics and Anti-tumor Activity • Usually seeking maximum tolerated dose or target dose based on pre-clinical exposure • Maximum biological dose • Participants have often failed other treatments • Important to have adequate performance status & “normal” organ function (except organ dysfxn trials) • Not an alternative to Hospice
Definitions of Key Concepts in Phase 1 Trials • Pharmacokinetics (PK): • “what the body does to the drug” • ADME: absorption, distribution, metabolism and excretion • PK parameters: Cmax, AUC (drug exposure), t1/2, Clearance, etc. • Pharmacodynamics (PD): • “what the drug does to the body” • e.g. nadir counts, non-hematologic toxicity, molecular correlates, biomarker changes, imaging endpoints
Phase I Design Strategy • Designs often based on tradition • Typically do some sort of dose escalation to reach targeted endpoint (MTD, OBD, MFD) • Has been shown to be safe and reasonably effective • Dose escalation based on mathematical model: Fibonacci, 2-fold escalation, Continuous Reassessment Method, etc.
Typical Scheme 1. Enter 3 patients at a given dose 2. If no toxicity, go to next dosage and repeat Step 1 3. a. If 1 patient has serious toxicity, add 3 more patients at that does (go to Step 4) b. If 1/6 have serious toxicity, consider MTD 4. a. If 2 or more of 6 patients have toxicity, drop down 1 dose to confirm safety b. If 1 of 6 has toxicity, increase dose and go back to step 1
A Phase 1b Study of CD40 Agonistic Monoclonal Antibody APX005M Together with Gemcitabine and nab-Paclitaxel with or without Nivolumab in Untreated Metastatic Pancreatic Ductal Adenocarcinoma (PDAC) PatientsPICI0002 (PRINCE) Mark H. O’Hara, Eileen M. O’Reilly, Rosemarie Mick, Gauri Varadhachary, Zev A. Wainberg, Andrew Ko, George Fisher, Osama Rahma, Jaclyn P. Lyman, Christopher R. Cabanski, Erica L. Carpenter, Travis Hollmann, Pier Federico Gherardini, Lacey Kitch, Cheryl Selinsky, Theresa LaVallee, Jingying Xu,Ovid C. Trifan, Ute Dugan, Vanessa M. Hubbard-Lucey, Ramy Ibrahim, Robert H. Vonderheide AACR March 31st, 2019
Study Design Phase 1b Cohort B1: 6 Subjects Gem, NP + APX005M 0.1 mg/kg Phase I Investigation of novel CD40 targeted agent in front-line metastatic pancreatic cancer Cohort B2: 6 Subjects Gem, NP + APX005M 0.3 mg/kg Cohort C1: 6 Subjects Gem, NP + nivo + APX005M 0.1 mg/kg Cohort C2: 6 Subjects Gem, NP + nivo + APX005M 0.3 mg/kg ClinicalTrials.gov Identifier: NCT03214250
Percent Change in Sum of Target Lesions (Best Response) Cohort B1: Gem/NP/APX005M 0.1 mg/kg Cohort B2: Gem/NP/APX005M 0.3 mg/kgCohort C1: Gem/NP/APX005M 0.1 mg/kg + nivo Cohort C2: Gem/NP/APX005M 0.3 mg/kg + nivo Clinical Snapshot date: 05MAR19Safety-evaluable Population