This study will treat patients with newly diagnosed PTCL, who have no prior systemic treatment for T-cell lymphoma. This study will assess the anti-tumor efficacy of golidocitinib using 2-year Progression-Free Survival rate as primary endpoint. In addition, it will help to understand what type of side effects may occur with the drug treatment.

Inclusion Criteria:

1. Male and female ≥ 18 years old.

2. ECOG performance status 0-2 with no deterioration over the previous 2 weeks.

3. Predicted life expectancy ≥ 12 weeks.

4. Patients must have histologically confirmed peripheral T-cell lymphoma. Eligible histological subtypes are restricted to the following:

   • PTCL, not otherwise specified (PTCL, NOS) (the proportion of PTCL-NOS subtype will not exceed 30% of all enrolled)
   • Angioimmunoblastic T-cell lymphoma (AITL)
   • Follicular T cell lymphoma
   • PTCL with T follicular helper (TFH) phenotype

5. Patients must have measurable disease according to the 2014 Lugano classification.

6. Patients must be treatment naïve with no prior systemic treatment for T-cell lymphoma.

7. Adequate bone marrow reserve and organ system functions.

8. Willing to comply with contraceptive restrictions.

Exclusion Criteria:

1. Intervention with any of the following:

   • Any investigational anti-cancer agents or study anti-cancer drugs from a previous clinical study.
   • Any cytotoxic chemotherapy from a previous treatment regimen.
   • Corticosteroids at dosages equivalent to prednisone > 40 mg/day within 7 days.

2. Major surgery procedure, or significant traumatic injury within 4 weeks.

3. Prior treatment with a JAK or STAT3 inhibitor.

4. Prior treatment with any onco-immunotherapy in 28 days.

5. Live vaccines within 28 days.

6. Patients currently receiving (or unable to stop use at least 14 days prior to receiving the first dose) medications or herbal supplements known to be Potent inhibitors or inducers of CYP3A.

7. Central nervous system or leptomeningeal lymphoma.

8. Past medical history of pneumonitis, drug-induced interstitial lung disease, radiation pneumonitis which required steroid treatment, or any evidence of clinically active interstitial lung disease.

9. Patients with disease condition which requires the treatment of immunosuppressants, biologics, or NSAID.

10. Active infections

11. Clinically significant cardiac disorders or abnormalities. Acute thrombotic diseases within 90 days.

12. Another malignancy within 5 years prior to enrollment with the exception of adequately treated in-situ carcinoma of the cervix, uterus, basal or squamous cell carcinoma or nonmelanomatous skin cancer.

13. Gastrointestinal disorders that is inability to swallow the formulated product or previous significant bowel resection that would preclude adequate absorption of golidocitinib.

14. History of hypersensitivity to active or inactive excipients of golidocitinib or drugs with a similar chemical structure or class.

15. Women who are breast feeding or pregnant.