Correlation Between Efficacy of Osimertinib and EGFR T790M Status and Ratio Via ddPCR in NSCLC

Study Overview
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Brief Summary
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Liquid biopsy is emerging as an essential tool in tumor monitoring and a potential alternative and supplement to tissue biopsy for tumor genotyping, especially in relapsed or metastatic diseases. Liquid biopsy methods for detecting T790M in ctDNA can be qualitative or quantitative, including amplification refractory mutation system PCR (ARMS-PCR), digital droplet polymerase chain reaction (ddPCR), and next generation sequencing (NGS)-based methods. Comparison of multiple detecting platform for EGFR mutations in plasma samples has been undertaken in studies to determine the most feasible assay in clinical practice. In this study, we will investigate the usefulness of ddPCR for quantitative detection of EGFR T790M mutation in peripheral blood, and compared the utility of ddPCR and NGS for guiding decisions regarding osimertinib therapy in NSCLC patients who had develop resistance to first- or second generation EGFR-TKIs.

Official Title
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Research on the Correlation Between Efficacy of Osimertinib and EGFR T790M Status and Ratio Via Digital Droplet PCR (ddPCR) From Peripheral Blood in NSCLC Patients

Conditions
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ddPCR, EGFR T790M, Osimertinib, Non-small Cell Lung Cancer

Intervention / Treatment
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* Drug: Osimertinib


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: histologically/cytologically confirmed stage IV NSCLC patients harboring sensitizing EGFR mutations; progression from first or second-generation EGFR-TKI confirmed by radiographic imaging; received both NGS test and ddPCR from peripheral blood simultaneously. Exclusion Criteria: progression from first- or second-generation EGFR-TKIs as adjuvant therapy; having received third-generation EGFR-TKIs prior to the gene tests; having received NGS test only or ddPCR test only.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Factorial Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Osimertinib<br>Osimertinib 80mg po daily | Drug: Osimertinib<br>* Osimertinib or chemotherapy<br>* Other names: pemetrexed;|
| Sham Comparator: Other treatments<br>chemotherapy or continuation of TKI monotherapy or in combination of anti-angiogenic agents | Drug: Osimertinib<br>* Osimertinib or chemotherapy<br>* Other names: pemetrexed;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PFS | Time from initiation of osimertinib or other anti-tumor treatment to progression or death from any cause | up to 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ORR | the sum of CR and PR rates | up to 1 year | 
| DCR | the sum of CR ,PR and SD rates | up to 1 year |