A Study to Evaluate JL18008 in Subject With HIV Immunological Non-Responders

Inclusion criteria

• Age 18 to 65 years (inclusive), male or female.
• Body mass index (BMI) 18.0 to 32.0 kg/m² (inclusive); body weight ≥50.0 kg for males and ≥45.0 kg for females.
• Receiving combination antiretroviral therapy (cART) for at least 48 months, with a stable antiretroviral regimen for at least 3 months prior to enrollment.
• Maintained HIV-1 RNA below 50 copies/mL for at least 36 months (the earliest test date more than 36 months before enrollment), including transient viral blips (single HIV-1 RNA measurement between 50 and 200 copies/mL after excluding laboratory error). At least two HIV-1 RNA results \<50 copies/mL must be available (one may be from screening).
• Immunological non-responder criteria: CD4⁺ T cell count ≤350 cells/μL within 1 year before screening. At least three CD4⁺ T cell counts ≤350 cells/μL within 4 years before enrollment, with intervals of ≥3 months between tests (the third may be from screening).
• Willing to use effective non-pharmacological contraception with partner from screening until 3 months after study completion, and no plan for sperm/egg donation during this period.
• Able to understand and provide written informed consent, and willing to comply with all protocol-specified visits and procedures.

Exclusion criteria

• Known allergy to the study drug or any of its excipients.
• Receipt of immunosuppressants, immunomodulators, or systemic cytotoxic therapy within 3 months before screening.
• Receipt of hormone therapy within 1 month before screening, except for daily doses ≤10 mg prednisone or equivalent.
• History of severe autoimmune disease requiring systemic treatment or hospitalization, or any active autoimmune disease requiring treatment (including multiple sclerosis).
• History of systemic infection (viral, bacterial, parasitic, or fungal) requiring systemic treatment and/or hospitalization, or other opportunistic infection, within 30 days before screening.
• Active tuberculosis lesion within 30 days before screening.
• Blood disorders associated with hypersplenism (e.g., thalassemia, hereditary spherocytosis, Gaucher's disease, autoimmune hemolytic anemia) or history of splenectomy.
• Chronic diarrhea.
• Severe cardiovascular disease within 6 months before screening, including myocardial infarction, unstable angina, congestive heart failure (NYHA class ≥II), or arrhythmia requiring medication.
• Uncontrolled hypertension, defined as resting systolic blood pressure \>140 mmHg and/or diastolic blood pressure \>90 mmHg on at least two repeated measurements on different days despite antihypertensive treatment.
• Positive hepatitis B surface antigen (HBsAg), or positive hepatitis C virus antibody (HCV-Ab) with detectable HCV-RNA, or active syphilis.
• Any of the following laboratory abnormalities at screening: hemoglobin \<90 g/L; neutrophil count \<1.5×10⁹/L; platelet count \<100×10⁹/L; serum creatinine \>1.5× upper limit of normal (ULN); alanine aminotransferase \>2.5×ULN; aspartate aminotransferase \>2.5×ULN; alkaline phosphatase \>2.5×ULN; total bilirubin \>1.5×ULN; international normalized ratio \>1.5; activated partial thromboplastin time \>1.5×ULN.
• Diagnosis of cancer within the screening period.
• Severe neurological or psychiatric disease, or history of seizures.
• History of drug abuse within 3 months before screening, or positive urine drug screen (including morphine, methamphetamine, ketamine, MDMA, THC, cocaine), or history of alcohol abuse.
• Participation in another clinical trial with receipt of investigational drug within 3 months before screening.
• Vaccination within 6 weeks before screening, or plan to receive any vaccination within 1 year after enrollment.
• Pregnancy, positive pregnancy test, or breastfeeding.
• Any other condition that, in the opinion of the investigator, makes the subject unsuitable for participation in this clinical study.