This study will assess the safety, tolerability and pharmacokinetics(PK) of Y-2 sublingual tablet in healthy adult subjects.

Inclusion Criteria:

• Inclusion Criteria

  1. Subject must be 18 to 55 years of age inclusive, at the time of signing the informed consent.

  2. Body Mass Index (BMI) ≥ 18 and ≤ 30 kg/m2 and weight ≥ 50kg at screening.

  3. A condition of general good health, as determined by the investigator or medically qualified designee based on a medical evaluation including medical history, physical examination, vital signs, laboratory profile and a 12-lead electrocardiogram (ECG).

  4. A female subject is eligible to participate if she is not pregnant, not breastfeeding, and at least one of the following condition applies:

     • Not a woman of childbearing potential (WOCBP) as defined in Appendix 1 Contraceptive Guidance, OR
     • A WOCBP who agrees to follow the contraceptive guidance in Appendix 1 Contraceptive Guidance from screening through at least 90 days after the last dose of study drug; a WOCBP must have a negative beta-human chorionic gonadotropin (β-hCG) test at screening and baseline prior to administration of investigational product.

Exclusion Criteria:

1. Subject has a history of any clinically significant cardiac, respiratory (including asthma, bronchospasm), renal, hepatic,gastrointestinal, psychiatric, neurologic, hematologic or rheumatic disease, or psychiatric disease or disorder, current acute or chronic infections, or other abnormality that may affect safety, or potentially influence the study results, judged by the investigator or designee.
2. Evidence or history of malignancy other than a successfully treated non-metastatic cutaneous squamous cell or basal cell carcinoma.
3. Treatment with biologic agents (such as monoclonal antibodies including marketed drugs) within 90 days or 5 half-lives (whichever is longer) prior to Day 1.
4. Receipt of any investigational product within 30 days or 5 halflives (whichever is longer) prior to Day 1.
5. Will have vaccination with live virus, attenuated live virus, or any live viral components within the 30 days prior to Day 1 or is to receive these vaccines at any time during study period or within 90 days after last dose.
6. Female subject who is pregnant, breastfeeding or is considering becoming pregnant during the study or for approximately 90 days after the last dose of study drug.
7. Male subject who is considering fathering a child or donating sperm during the study or for approximately 90 days after the last dose of study drug.
8. Consideration by the investigator, for any reason, that the subject is an unsuitable candidate to enroll this study.