This is a cross-sectional, non-interventional qualitative study using individual interviews to investigate determinants of persistence with 3rd generation EGFR-TKI osimertinib as adjuvant therapy among patients with early-stage NSCLC in China. Approximately 100 participants will be enrolled, comprising around 85 patients and 15 physicians. All participants will be interviewed online or in-person using a COM-B (Capability, Opportunity, Motivation - Behaviour) based guide. Interviews will be conducted in waves, recorded, transcribed, and analysed using both deductive and inductive methods.

For patient

Inclusion Criteria:

• Adults (≥18 years) with NSCLC who have received osimertinib as the 3rd generation EGFR-TKI adjuvant therapy and meet one of the following: Patients who received adjuvant osimertinib for less than 34 months and discontinued treatment (off treatment), or Patients who received adjuvant osimertinib for at least 34 months (either off treatment or still on treatment).
• For off treatment patients, discontinuation or completion of osimertinib is required to occur within 6 months by screening.
• Willing and able to provide informed consent, participate in an online or in-person qualitative interview, and permit audio recording for research purposes.

Exclusion Criteria:

• Prior receipt of 3rd generation EGFR-TKI as adjuvant therapy as part of any interventional clinical trial.
• Prior receipt of 1st generation EGFR-TKIs as adjuvant therapy.
• Evidence of cognitive impairment that would likely to interfere with participation in an interview, as informally assessed during screening.
• Unaware of or do not understand their own medical condition.

For physicians

Inclusion Criteria:

• Licensed medical oncologists, thoracic surgeons, or pulmonologists with experience of prescribing osimertinib as adjuvant treatment and actively managing patients who will participate the interview.
• Managed 5 patients with early-stage NSCLC receiving osimertinib within the past 6 months.
• Holding a professional title equivalent to or higher than attending physician.
• Willing and able to provide informed consent, participate in an online or in-person qualitative interview, and permit audio recording for research purposes.

Exclusion Criteria:

• Unable or unwilling to follow study procedures.

Include adult patients with early-stage NSCLC who received adjuvant osimertinib after curative surgery, as well as physicians experienced in prescribing adjuvant osimertinib.

Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal Vivli.org. All requests will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA PhRMA Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

When a request has been approved AstraZeneca will provide access to the anonymized individual patient-level data via secure research environment Vivli.org. Signed Data Usage Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information.