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Clinical trials in brain tumours- What you always wanted to know but were afraid to ask. Zarnie Lwin Department of Medical Oncology, Mater Adult Hospital November 2011. Stupp Treatment Schema. Concomitant. Adjuvant TMZ. TMZ/RT*. R. 0. 6. 10. 14. 18. 22. 26. 30. Weeks. RT Alone.
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Clinical trials in brain tumours- What you always wanted to know but were afraid to ask Zarnie Lwin Department of Medical Oncology, Mater Adult Hospital November 2011
Stupp Treatment Schema Concomitant Adjuvant TMZ TMZ/RT* R 0 6 10 14 18 22 26 30 Weeks RT Alone Temozolomide 75 mg/m2 po qd for 6 weeks, then 150–200 mg/m2 po qd d1–5 every 28 days for 6 cycles Focal RT daily — 30 x 200 cGy Total dose 60 Gy *PCP prophylaxis was required for patients receiving TMZ during the concomitant phase.
What are the different types of trials ? • Phase I • Phase II • Phase III • Phase IV
How are clinical trials developed ? • Current scientific literature • Gaps in knowledge • Postulates and hypothesis • Preliminary data on hypothesis • Is this logical ? • Think tanking and collaboration • Interstate, international, collaborative groups discussions
What happens next ? • Trial protocol designed and written up • Scientific merit, novel idea, feasibility • Funding very important • Research ethics approval • Multi-instituion ? Need all institutions to approve • Hypothesis, objectives, outcomes • Overall survival • Statitician for clinically meaningful numbers
Where are these trials available ? • Approved and funded clinical trial • Selection of clinical sites / hospitals • Invited to participate • Review, feasibility, patient volume considered • Expression of interest • Approved at hospital X
How are these trials advertised ? • Principal investigator responsible • Tumour boards • Interhospital referrals • Clinical trials registries
Am I eligible ? • Inclusion criteria • Exclusion • Specific populations e.g elderly • Specific grade of tumour • Specific biomarkers in tumour tissue • Other cancers • Other medical problems • Enrolled in other trial and had other new agents
Who will explain the trial design to me ? • Initial consultation with Principal or Subinvestigator at hospital X • Consent very important • Can never consent immediately • Must be able to understand and have independent capacity to consent • Proxy consent not allowed in majority • English versus non english speaking patients and families
Why am I not getting the new treatment even though I am on a trial ? • Comparator/control arm • Randomization centralized • Low grade glioma trials may not require new treatment to start immediately • Must be compared to standard of care • Sometimes in recurrent disease there is no standard of care
Do I have to pay for anything ? • Study drug will be supplied • Investigations will be covered in cost • Parking ? • CT scans ? • Emergency or hospital admissions ?
What is randomization ? Randomization vs. stratification Centre, tumour biomarkers, ECOG Blinding and unblinding SAE and homeopathic medications
How do I know if the new drug is working ? • Strict guidelines in study for follow up appointments • MRI scan intervals • Quality of life questionnaires • Mini mental or CogState tests • Decrease in steroid dosages
What if I decide to discontinue ? • Must inform oncologist • No clinical trial ever compulsary • Consent very important • Voluntary discontinuation versus toxicities • Will still be offered standard of care • Will not be turned away from clinic
When do I stop the new treatment ? • As per protocol • Watch and wait • True progression • Trial discontinued due to safety reports in interim analysis
When will I know the results of the trial ? • Data analyses • Data needs to mature • Abstract presented at major scientific meetings • Scientific manuscript published • Media release
Are all clinical trial results released to media? • Positive versus negative results • Important negatives • Potential harm • Costs
What happens to the new treatment /drug ? • Goes up one Phase • Phase II • Phase III • Phase IV
What happens to the new treatment /drug ? • Various approvals • FDA • TGA • Access schemes • Patient covers the cost • PBS
Why are some new drugs unavailable to us ? • Cost –effectiveness • Different countries have different thresholds • Still requiring confirmation data from more larger trials • Not yet endorsed in standard treatment guidelines
What should I do if hospital X is too far to travel ? • Satellite trial sites may open • Hospital will adhere to follow up trial protocol even after trial closes • Discuss with oncologist
Why should I participate in clinical trials? • The treatments of today are results of previous • Robust trial results require large numbers • Access to newer agents as they are investigated • Brain tumours are still unmet need compared to other solid tumours
Are clinical trials always open for me? • Designated time frame or total numbers as target • Once accrued - trial closes for data maturation and analyses • Newer trials opening pending on approvals
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