The goal of this clinical trial is evaluating the efficacy and safety of Jitongning tablets in participant population. The main questions it aims to answer are:

• Based on the proportion of participants who achieved improvement in ASAS20, evaluate whether the efficacy of Jitongning tablets is superior to placebo in active ax-SpA adult participants.

• Evaluate the efficacy of Jitongning tablets in improving other key functions and symptom outcomes.

• Evaluating the safety of Jitongning tablets in adult ax-SpA participants. Participants will

  1. take orally Jitongning tablets or a simulated agent of Jitongning tablets.
  2. Receive examinations and follow-up visits.

Inclusion Criteria:

All of the following standards must be met:

1. Age range from 18 to 65 years old (including 18 and 65 years old), regardless of gender;
2. Meets the diagnostic criteria for axial osteoarthritis recommended by ASAS in 2009, and the condition is in an active phase. The criteria for determining disease activity are to meet two criteria: Bass ankylosing spondylitis disease activity index (BASDAI) ≥ 40mm (0-100mm, evaluated using VAS); Spinal pain score ≥ 40mm (0-100mm, evaluated using VAS);
3. Conforming to the traditional Chinese medicine syndrome differentiation standards for kidney yang deficiency and blood stasis obstruction syndrome;
4. CT examination of sacroiliac arthritis grades I (A) to II (B) (both included);
5. Human leukocyte antigen B27 (HLA-B27) is positive;
6. Elevated C-reactive protein (CRP)/hypersensitive C-reactive protein (hsCRP) and/or erythrocyte sedimentation rate (ESR);
7. Voluntarily participate in this clinical trial and sign an informed consent form.

Exclusion Criteria:

Those who meet any of the following criteria cannot be included in this experiment:

1. Received non-steroidal anti-inflammatory drugs within 2 weeks before enrollment;
2. Within 4 weeks before enrollment, he received traditional Chinese patent medicines and simple preparations or traditional Chinese medicine decoction, chemical drugs (such as sulfasalazine, methotrexate, leflunomide, hydroxychloroquine, cyclophosphamide, azathioprine, etc.), opioid analgesics (such as methadone, morphine, etc.), JAK inhibitor drugs (such as tofatib, etc.), and systemic glucocorticoid treatment;
3. Received spinal or joint surgery treatment within 8 weeks prior to enrollment;
4. Within 12 weeks prior to enrollment, biological agents with therapeutic effects on spinal arthritis have been used;
5. Within 6 months prior to enrollment, corticosteroid injections were received into the joint cavity or spine/paravertebral area;
6. CT indicates disappearance of sacroiliac joint space or complete spinal rigidity;
7. Subjects diagnosed with other rheumatic immune system diseases or immune deficiency syndrome, such as active ulcerative colitis, psoriasis, uveitis, etc;
8. Those who have fertility requirements within six months;
9. Pregnant or lactating women;
10. Suspected or actual drug, substance, or alcohol abuse;
11. Within 3 months prior to the trial or currently participating in clinical trials;
12. Serious heart, liver, kidney, brain, mental, and neurological disorders that affect informed consent and/or expression or observation of adverse events;
13. Abnormal liver function (elevated levels of alanine or alanine aminotransferase above the upper limit of normal values); Abnormal renal function (serum creatinine levels above the upper limit of normal values);
14. The researchers believe that it is not suitable to participate in this experiment.