A Trial to Evaluate the Efficacy and Safety of Methoxyetomidate Hydrochloride for Injection (ET-26) for the Induction of General Anesthesia in Elective Surgery Subjects

Inclusion Criteria:

1. Inpatients requiring tracheal intubation under general anesthesia for Non-emergency,non-cardiothoracic, non-extracranial elective surgery estimated operation duration ≥ 0.5h;
2. Age ≥ 18 and ≤ 70 years old, gender is not limited;
3. ASA（American Society of Anesthesiologists） Class I-II;
4. Body mass index (BMI) 18 ~ 30 kg/m2 (including boundary value);
5. Serum cortisol concentration test is normal or abnormal but judged no clinicalsignificance by the investigator;
6. Vital signs during screening: respiratory rate≥ 10 and ≤ 24 breaths /minute; Whenbreathing air, pulse oxygen saturation (SpO2)≥95%; Systolic blood pressure (SBP) ≥ 90mmHg and ≤160mmHg; diastolic blood pressure (DBP) ≥ 60mmHg and ≤100mmHg; heart rate (ECG results) ≥ 55 and ≤ 100 beats/min;
7. Subjects must understand the procedures and methods of this study and be willing tosign informed consent and strictly abide by this trial protocol to complete the study.

Exclusion Criteria:

1. Subjects with contraindications to general anesthesia or previous history ofanesthesia accidents, and other systemic medical history that increases the risk ofanesthesia;
2. Known or suspected family history of malignant hyperthermia;
3. Known or suspected of being allergic or contraindicated to the procedural medicationprescribed in each component or regimen of the experimental drug, suspected ofepilepsy or severe liver and kidney dysfunction;
4. Difficulty in intubation or ventilation is expected (Modified Mallampati Score of Ⅲand Ⅳ);
5. Presence of any of the following respiratory management risks before/at screening: 1)history of asthma, stridor; 2) Patients with sleep apnea syndrome;
6. Any of the following drugs or treatments were used prior to screening: 1) those whoparticipated in any drug clinical trial within 1 month prior to screening; 2) Haveused drugs or treatments that affect cortical function within 3 days before screening;

3. Use of drugs that may affect the QT interval within 2 weeks prior to screening;

7. The laboratory examination indicators during the screening period meet the followingstandards:

1. AST and /or ALT ≥ 3×ULN; 2)TBIL≥1.5×ULN； 3) Hb≤90 g/L (and no blood transfusion within 14 days); 4)ANC≤1.5×109/L； 5)PLT≤80×109/L； 6) Blood Serum creatinine ≥1.5×ULN; 8. Pregnantand lactating women; the reluctance of fertile women or men to use contraception throughoutthe trial; subjects (including male subjects) who had pregnancy plans within three monthsof the trial; 9. Subjects who have any other factors deemed unsuitable for participation inthis study by the investigator.