RECIST 1.1 and Oncology Trial Endpoints
MERIT Webinar Key Takeaways

IN-DEPTH INSIGHTS

MERIT’s webinar also provided more in-depth information on the key topics outlined above.

• Imaging endpoints derived from RECIST 1.1
  • Tumor Response Rate endpoint: Objective Response Rate (ORR)
    • Proportion of patients with tumor size reduction of a predefined amount and for a minimum period
    • Proportion of patients with Best Overall Response of Complete Response (CR) or Partial Response
    • Often used in Phase II settings or single arm studies
  • Time to Event Endpoint: Progression Free Survival
    • Time from randomization until objective tumor progression or death, whichever occurs first
    • Usually used as surrogate endpoint in advanced disease setting
    • Phase II and III
    • Radiologic progression date (Progressive Disease [PD] by RECIST)

• Common mistakes and special considerations for data collection using RECIST 1.1:
  • Lesion direction measurements need to adjust from timepoint to timepoint to ensure the longest diameter is being accurately measured
  • The longest diameter must be measured per RECIST 1.1 to accurately capture the size of the lesion
  • Reproducibility in RECIST 1.1 is very important. Using the right imaging protocol to ensure that all imaging is performed and assessed in a consistent manner is crucial.
    • Readers should always make sure the measurements are taken on the same phases of the CT scan.
    • If a visit spans two days, it’s important to be sure scans from the correct date are being assessed.

• Key elements collected in the eCRF form while reading RECIST 1.1:
  • Individual lesion level
  • Lesion category level
  • Subject level data fields

Attendings at the webinar provided some lively discussion in the Q and A session. See below for highlights.

HIGHLIGHTS FROM Q & A

Q If all target lesions from the first scan to sixth scan have disappeared, but there are still non-target lesions that are less than 10 mm, can this be classified as CR?
A No, this wouldn’t constitute CR. If a timepoint shows complete disappearance of target lesions but there are still non-target lesions, you would record CR for the target lesions and Non-CR/Non-PD (NN) for the non-target lesions. This would translate into an overall response of PR for the timepoint.

Q We are transitioning from pre-clinical to clinical studies, how do we get started with imaging endpoints?
A First, closely examine the preclinical data and look at the evidence collected to determine the targeted disease states. That will suggest what response criteria should be used for the desired endpoint. If it’s a disease state with simple solid tumors, that will typically call for RECIST 1.1, which will then determine what imaging modality should be used. Some disease types like lymphoma or glioma will require different response criteria.

Q If the size of the lesion is non-measurable or extremely small, what does the industry view as the default? It seems as if this could be quite subjective. Should we use the 5 mm?
A Yes, the standard would be to enter the measurement as 5 mm regardless of slice thickness. Whoever reads the scan determines if the lesion presents and that it hasn’t disappeared even if it’s very small. If they aren’t confident that they can perform a caliper measurement, they can simply use a marking tool to make a circle or a box and say it’s too small to measure. Then they enter the default measurement of 5 mm.

Q When the BOR is calculated, if there are patients with non-measurable lesions and readers have entered several 5 mm values, does that have impact on the overall response?
A This is a very complicated question, but usually it should not have impact on the overall response assessment.

WITH MERIT ONCOLOGY SOLUTIONS, YOU BENEFIT FROM THE FOLLOWING:

Comprehensive Imaging Services: We provide end-to-end central oncology imaging services from acquisition and upload, to storage, QC review, masked independent review, and data export.

Single System: Unlike others that depend on separate applications, our proprietary software, EXCELSIOR™, delivers automation in a single system for all image and workflow management that supports lesion segmentation with the corresponding response criteria such as RECIST1.1.

Collaborative Partnership: We prioritize a collaborative, partnership-driven approach for all projects with scalable solutions and personalized attention. We adapt quickly to meet your needs. If you’re looking for an oncology imaging services provider that will value your partnership and make your study a priority, consider MERIT.

To view this on-demand webinar, click here.