Inclusion Criteria:
1. Male participants aged 18 to 55 years old (inclusive).
2. Diagnosed with premature ejaculation (PE) per the definition issued by the International Society for Sexual Medicine (ISSM).
3. Participants achieved ≥4 coital ejaculations during the run-in period, with intravaginal ejaculatory latency time (IELT) ≤ 2 min in ≥75% of all sexual intercourse attempts.
4. Participants had a Premature Ejaculation Diagnostic Tool (PEDT) total score ≥ 11.
5. Participants maintained a stable sexual relationship with the same adult female partner for a minimum of 3 months, and intended to sustain this relationship throughout the study period.
6. Participants agreed to complete ≥4 coital ejaculations every 28 days during the double-blind treatment period, and were capable of completing all study visits, examinations, assessments and other trial-related procedures as specified in the protocol.
7. Participants fully understood the study procedures, volunteered to participate in this trial, and provided written informed consent.
8. Participants must use reliable contraceptive measures from the date of informed consent signature until 3 months after the last study drug administration.
Exclusion Criteria:
1. Participants with known hypersensitivity to any components of VV913 capsules or its placebo, or a prior history of hypersensitivity to selective serotonin reuptake inhibitors (SSRIs) or serotonin-norepinephrine reuptake inhibitors (SNRIs).
2. Participants suffering from erectile dysfunction, defined as a total score ≤21 on the International Index of Erectile Function-5 (IIEF-5).
3. Participants who had genitourinary diseases that may impair sexual function (e.g., prostatitis, phimosis, urinary tract infection, etc.) or underwent genitourinary surgery within 28 days prior to screening and during the baseline period.
4. Participants or their female partners diagnosed with psychiatric disorders by psychiatrists, such as major depressive disorder, generalized anxiety disorder, bipolar I disorder, bipolar II disorder, panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, alcohol use disorder, schizophrenia or other psychiatric disorders.
5. Participants' female partners who are pregnant, breastfeeding or planning pregnancy, or suffering from gynecological diseases or receiving relevant treatments that restrict sexual activity.
6. Participants with diseases that may affect the absorption of oral medications, such as active enteropathy, partial or complete intestinal obstruction, chronic diarrhea, etc.
7. Participants with severe cardiovascular diseases judged by investigators to potentially increase trial risks, including heart failure (NYHA Class II-IV), clinically significant conduction abnormalities (e.g., second- or third-degree atrioventricular block, sick sinus syndrome, etc.), severe or unstable coronary artery disease/ischemic heart disease, severe carotid artery stenosis, left ventricular outflow tract obstruction, etc.
8. Participants with active malignant tumors, or a medical history of malignant tumors within 5 years before screening (except completely resected and cured cutaneous squamous cell carcinoma).
9. Participants with clinically significant liver or renal function abnormalities, i.e., serum ALT and/or AST \> 2 times the upper limit of normal (ULN), or serum creatinine \> 1.2 times ULN.
10. Participants with uncontrolled hypertension (systolic blood pressure \>160 mmHg or diastolic blood pressure \>95 mmHg) or hypotension (systolic blood pressure \<90 mmHg or diastolic blood pressure \<60 mmHg).
11. Participants who previously discontinued SSRIs or SNRIs due to adverse reactions, or experienced syncope after administration of such drugs.
12. Participants who received any anti-premature ejaculation treatment within 28 days before randomization.
13. Participants who used monoamine oxidase inhibitors, strong CYP3A4 inhibitors, moderate CYP3A4 inhibitors, strong CYP3A4 inducers or moderate CYP3A4 inducers within 28 days before randomization, or required concomitant use of such agents during the trial.
14. Participants who participated in another clinical trial and received investigational medicinal products or medical device treatment within 3 months prior to screening.
15. Participants with other conditions deemed ineligible for trial participation by the investigator.
