The purpose of this study is to compare effectiveness of TAK-788 as first-line treatment with that of platinum-based chemotherapy in participants with locally advanced or metastatic non-small cell lung cancer (NSCLC) whose tumors has epidermal growth factor receptor (EGFR) exon 20 insertion mutations.

Participants will be randomly assigned to one of the two treatment groups- TAK-788 group or Platinum-based chemotherapy group.

Participants will receive TAK-788 orally and pemetrexed/cisplatin or pemetrexed/carboplatin via vein until the participants experience worsening disease (PD) as assessed by blinded independent review committee (IRC), intolerable harmful effects or another discontinuation criteria.

The drug being tested in this study is called TAK-788. TAK-788 is being tested to evaluate the efficacy as a first line treatment compare with platinum-based chemotherapy in the participants with locally advanced or NSCLC whose tumors harbor EGFR exon 20 insertion mutations.

The study will enroll approximately 318 patients. Participants will be randomly assigned to one of the two treatment groups-

• TAK-788 Group (Arm A)
• Platinum-based Chemotherapy Group (Arm B)

The participants will be administered with TAK-788 orally in arm A and pemetrexed/cisplatin or pemetrexed/carboplatin intravenously (IV) in arm B until the participants experience progressive disease (PD) as assessed by blinded independent review committee (IRC), intolerable toxicity or another discontinuation criteria. Participants in the chemotherapy group may cross over to treatment with TAK-788 after IRC-assessed PD is documented. Randomized treatment with TAK-788 or platinum-based chemotherapy may be continued after PD, at the discretion of the investigator and with the sponsor's approval, if there is still evidence of clinical benefit.

This multi-center trial will be conducted in United States (US), Europe, and Asia. The overall time to participate in this study is until 3 years after the last participant is randomized. Participants will make multiple visits to the clinic and will be followed for survival, subsequent anticancer therapy, subsequent disease assessment outcome until disease progression on a subsequent anticancer therapy, and participant-reported health status (EuroQoL-5 Dimensions-5 Levels [EQ-5D-5L]) for 3 years after the last participant is randomized in the study and 30 days after the last dose of study drug for safety follow-up.

Inclusion Criteria:

• Male or female adult patients (aged 18 years or older)
• Histologically or cytologically confirmed nonsquamous cell locally advanced not suitable for definitive therapy, recurrent, or metastatic (Stage IV) NSCLC
• Documented epidermal growth factor receptor (EGFR) in-frame exon 20 insertion mutation assessed by a clinical laboratory improvements amendment (CLIA)-certified (US sites) or an accredited (outside of the US) local laboratory The EGFR exon 20 insertion mutation can be either alone or in combination with other EGFR or human epidermal growth factor receptor 2 (HER2) mutations except EGFR mutations for which there are approved anti-EGFR tyrosine kinase inhibitors [TKIs] (ie, exon 19 del, L858R, T790M, L861Q, G719X, or S768I, where X is any other amino acid)
• Adequate tumor tissue available, either from primary or metastatic sites, for central laboratory confirmation of EGFR exon 20 insertion mutation
• At least 1 measurable lesion per RECIST Version 1.1
• Life expectancy ≥3 months
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1
• Adequate organ and hematologic function as defined by blood transfusions with a recommended >/ 14 day washout period.

Exclusion Criteria:

• Received prior systemic treatment for locally advanced or metastatic disease, including local administration, such as intra-pleural injection of anticancer medication with the exception noted below:

  • Neoadjuvant or adjuvant chemotherapy/immune therapy for Stage I to III or combined modality chemotherapy/radiation for locally advanced disease is allowed if completed >6 months before the development of metastatic disease.

• Received radiotherapy ≤14 days before randomization or has not recovered from radiotherapy-related toxicities

• Received a moderate or strong cytochrome P450 (CYP)3A inhibitor or moderate or strong CYP3A inducer within 10 days before first dose of TAK-788

• Have been diagnosed with another primary malignancy other than NSCLC

• Have current spinal cord compression or leptomeningeal disease

• Have uncontrolled hypertension. Participants with hypertension should be under treatment on study entry to control blood pressure

• Received a live vaccine within 4 weeks before randomization per Summary of product characteristics (SmPCs) for pemetrexed, cisplatin, and carboplatin

• Taking medication(s) known to be associated with the development of torsades de pointes.

Takeda provides access to the de-identified individual participant data (IPD) for eligible studies to aid qualified researchers in addressing legitimate scientific objectives (Takeda's data sharing commitment is available on https://clinicaltrials.takeda.com/takedas-commitment?commitment=5). These IPDs will be provided in a secure research environment following approval of a data sharing request, and under the terms of a data sharing agreement.

IPD from eligible studies will be shared with qualified researchers according to the criteria and process described on https://vivli.org/ourmember/takeda/. For approved requests, the researchers will be provided access to anonymized data (to respect patient privacy in line with applicable laws and regulations) and with information necessary to address the research objectives under the terms of a data sharing agreement.