A Study to Learn the Safety and Efficacy of HLX37 in Combination With Chemotherapy for First-line Treatment in Adult Participants With Locally Advanced or Metastatic Non-Small Cell Lung Cancer

• Investigational drug: HLX37 dose1, IV, Q3W (Drug): HLX37: HLX37 will be given at dose1 in Stage I via intravenous (IV) infusion once every 3 weeks (Day 1 \[D1\] of each cycle). HLX37 will be given in Stage II at a dose to be determined based on Stage I study results via IV infusion once every 3 weeks (D1 of each cycle).
• PEMBROLIZUMAB (alone or when added to a regimen above) (Drug): Pembrolizumab: Pembrolizumab will be given at a flat dose of 200 mg via IV infusion once every 3 weeks (D1).
• Carboplatin (Investigator discretion) (Drug): Carboplatin: AUC = 5 up to a dose of 750 mg, or AUC = 6 up to a dose of 900 mg, based on local treatment guidelines, IV, once every 3 weeks (D1), given over 15-60 min.
• Paclitaxel or Nab-Paclitaxel (Drug): Paclitaxel: 175 mg/m2 or 200 mg/m2, based on local treatment guidelines, IV, once every 3 weeks (D1), given continuously over no less than 3 h. All participants should be pretreated with oral or intravenous steroids and antihistamines according to the local approved product label and/or standard practice. Other pretreatment medications should be administered per standard practice. Nab paclitaxel: 100 mg/m2, IV, on D1, D8, and D15 of each 3-week cycle, given continuously over no less than 30 min.
• Pemetrexed (1) (Drug): Pemetrexed: 500 mg/m2, IV, on D1 of each 3-week cycle, given continuously over no less than 10 min.
• Investigational drug: HLX37 dose2, IV, Q3W (Drug): HLX37 will be given at dose2 (treatment group 2) in Stage I via intravenous (IV) infusion once every 3 weeks (Day 1 \[D1\] of each cycle). HLX37 will be given in Stage II at a dose to be determined based on Stage I study results via IV infusion once every 3 weeks (D1 of each cycle).

Primary outcomes

• PFS assessed by BICR (Phase2&3) [From date of the first dose of study drug until the date of death from any cause, assessed up to 24 months]: Description: Defined as the time from randomization to the first documentation of PD (RECIST v1.1) or death due to any cause (whichever occurs first)
• ORR assessed by BICR (phse2) [From date of the first dose of study drug until the date of death from any cause, assessed up to 24months]: Defined as the proportion of participants who achieve a best overall response of CR or PR
• OS (phase3) [From date of the first dose of study drug until the date of death from any cause, assessed up to 50 months]: OS (Phase3):Defined as the time from randomization to death due to any cause Time Frame: Assessed up to appoximately 50 months from enrollment

Secondary outcomes

• DOR [Assessed up to appoximately 35 months from enrollment]: Defined as the time from the first documented objective response to PD or death
• ORR assessed by investigator [From date of the first dose of study drug until the date of death from any cause, assessed up to 24 months]: Defined as the proportion of participants who achieve a best overall response of CR or PR
• PFS assessed by investigator [From date of the first dose of study drug until the date of death from any cause, assessed up to 24 months]: Defined as the time from randomization to the first documentation of PD (RECIST v1.1) or death due to any cause (whichever occurs first)
• DCR [From date of the first dose of study drug until the date of death from any cause, assessed up to 24 months]: defined as the proportion of participants who achieve a best overall response of CR or PR or an SD lasting for 12 weeks
• Incidence of adverse events [Assessed up to appoximately 42 months from enrollment]: Incidence of adverse events

Sex: All, ages: 18 Days to 75 Days

Inclusion Criteria:

* Have a full understanding of the study content, process, and possible adverse reactions before the study, and sign the informed consent form (ICF); voluntarily participate in the study; be able to complete the study as per protocol requirements; 2. Aged ≥ 18 years and ≤ 75 years at the time of signing the ICF, male or female; 3. Life expectancy ≥ 3 months; 4. An ECOG performance status score of 0-1 within 7 days prior to the first dose; 5. Histologically or cytologically confirmed, locally advanced (stage IIIB/IIIC) or metastatic(stage IV) NSCLC not eligible for radical treatment (complete surgical resection, concurrent/sequential radiochemotherapy) according to the Union for International Cancer Control and the American Joint Committee on Cancer (AJCC) TNM staging system for lung cancer (8th edition); Note: For participants with locally advanced (stage IIIB/IIIC) disease not eligible for radical concurrent/sequential radiochemotherapy, a documented evaluation by a specialist is required.

  6\. Absence of known sensitizing EGFR mutations or ALK, ROS1, NTRK, BRAF, MET14 exon skipping or targetable RET driver gene alterations. Participants with nsq-NSCLC or those with sq-NSCLC who have never smoked must provide previous tissue specimen test results confirming negative EGFR, ALK, and other related gene alterations; otherwise, tumor tissue samples should be provided for relevant tests at the study site. For participants with sq-NSCLC who have a previous or current smoking history, if EGFR and/or ALK and other related gene statuses are unknown, the relevant tests are not required before enrollment in this study; 7. Agree to provide archived tumor tissue specimens that meet the testing requirements (from the most recent surgery or biopsy, preferably within half a year before randomization) or agree to undergo a biopsy to collect tumor tissue for PD-L1 expression testing;Have not previously received systemic anti-tumor therapy for advanced or metastatic NSCLC; participants who have received adjuvant or neoadjuvant therapy are eligible for this study if the adjuvant/neoadjuvant therapy had been completed at least 6 months before the diagnosis of locally advanced/recurrent or distant metastatic NSCLC; 9. At least one measurable lesion by central imaging as per RECIST v1.1 within 4 weeks before the first dose, which is suitable for repeated measurement; note: previously irradiated lesions cannot be used as the target lesions; 10. The first dose of the study treatment should be at least 28 days apart from any previous major surgery, medical device treatment, and local radiotherapy (except palliative radiotherapy for bone lesions), at least 2 weeks apart from any previous non-specific immunomodulatory treatment (such as interleukin, interferon, thymosin, tumor necrosis factor, etc., excluding IL-11 for platelets decreased), at least 7 days apart from any previous treatment with traditional Chinese medicine for anti-tumor indications, and at least 1 year apart from any previous treatment with immune checkpoint inhibitors, immune checkpoint agonists, immune cell therapy, and the last dose of any anti-angiogenic agents; any treatment-induced AEs should resolve to Grade ≤ 1 as per CTCAE v6.0 (except for alopecia);

Exclusion Criteria:

* NSCLC with small cell lung cancer or neuroendocrine carcinoma confirmed by tumor histology or cytology; 2. History of other malignant tumors within 3 years prior to the first dose of the study treatment, except cured cervical carcinoma in situ or cutaneous basal cell carcinoma; 3. History of AEs leading to permanent discontinuation of immunotherapy, or history of Grade ≥ 2 immune-related pneumonitis or immune-related myocarditis; 4. History of (non-infectious) interstitial lung disease (ILD) with current need for steroid treatment; or currently active ILD, or suspected risk of ILD aggravation or unsuitability for participation in this study as considered by the investigator via imaging at screening; 5. History of severe allergic reactions to macromolecular protein preparations/monoclonal antibodies, or known allergy to any components in the investigational drug formulation; known allergy to any components of carboplatin, paclitaxel, albumin-bound paclitaxel, or pemetrexed. Participants are allowed to be enrolled if they are only allergic to either paclitaxel or albumin-bound paclitaxel, in whom the use of the other paclitaxel preparation is safe as assessed by the investigator; 6. Active systemic infectious diseases (such as those requiring antibiotic treatment) within 2 weeks before the first dose; 7. Known history of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation; 8. Clinically symptomatic and uncontrolled pleural effusion, pericardial effusion, or ascites; 9. Having received thoracic radiotherapy > 30 Gy within 6 months prior to randomization; having received non-thoracic radiotherapy > 30 Gy within 4 weeks prior to randomization or palliative radiotherapy ≤ 30 Gy within 1 week prior to randomization; 10. Imaging evidence of the following during the screening period: a. tumor invasion into large blood vessels or important organs (such as main bronchus) or risk of tracheoesophagealfistula or esophagopleural fistula; b. tumor encapsulation of large blood vessels with vascular stenosis, or cavitation or necrosis of lung lesions, which will lead to the risk of bleeding should the participant be enrolled in the study, as assessed by the investigator; 11. Any poorly-controlled cardiovascular and cerebrovascular clinical symptoms or diseases, including but not limited to: (1) NYHA Class II or greater heart failure or left ventricular ejection fraction (LVEF) < 50%; (2) unstable angina pectoris; (3) myocardial infarction or cerebrovascular accident within 6 months (except lacunar infarction, slight cerebral ischemia, or transient ischemic attack); (4) poorly controlled arrhythmia (including QTc intervals ≥ 450 ms for males and ≥ 470 ms for females) (QTc intervals are calculated by Fridericia's formula); 12. Occurrence of the following diseases within 12 months before the first dose: history of varicose veins in the lower esophagus, severe ulcers, unhealed wounds, gastrointestinal perforation, abdominal fistula, gastrointestinal obstruction, abdominal abscess, or acute gastrointestinal bleeding; occurrence of the following diseases within 6 months before the first dose: any arterial thromboembolic events, NCI CTCAE v6.0 Grade 3 or greater venous thromboembolism, transient ischemic attack, cerebrovascular accident, hypertensive crisis, history of hypertensive encephalopathy, or history of acute exacerbation of chronic obstructive pulmonary disease; current hypertension with a systolic blood pressure of ≥ 150 mmHg or a diastolic blood pressure of ≥ 100 mmHg after treatment with oral antihypertensive drugs;