Please assess the completion status of the following clinical trial:

Trial Title: Efficacy and Safety of Postoperative Intravenous Parecoxib Sodium Followed by Oral Celecoxib in Osteoarthritis Patients

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: QUADRUPLE
- Phase: PHASE4
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~1. The subject is scheduled to undergo elective unilateral total knee arthroplasty because of OA, performed under a standardized regimen of general anesthesia, as specified in this protocol.~2. Evidence of a personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study.~3. The subject is a male or female over 18 years of age.~4. Subjects of childbearing potential must agree to use an effective method of contraception throughout the study and for 42 days after the last dose of assigned treatment.~5. Total duration of the surgical procedure is four hours or less.~6. ASA grade 1-3 subjects.~7. Subjects who are willing and able to comply with scheduled visits, treatment plan, laboratory tests, standardized rehabilitation scheme, and other study procedures.~8. The subject is in satisfactory health as determined by the investigator on the basis of medical history and physical exam.~9. The subject must demonstrate sufficient psychomotor dexterity and cognitive capacity to use intravenous (IV) patient-controlled analgesia(PCA).~10. The subject who live near to the hospital may be considered prior for the concern of convenient and sufficient follow-up.~    -~Exclusion Criteria:~1. The subject requires a revision to previous knee arthroplasty and/or is having a bilateral knee arthroplasties.~2. The subject requires an emergency knee arthroplasty.~3. Subject uses opioids more than three days/ week prior to operation unless they discontinue the opioids two months prior to screen.~4. Subject has a known hypersensitivity to COX-2 specific inhibitors, sulfonamides, lactose, NSAIDs, opioids or acetaminophen/paracetamol.~5. The subject has a history of arthritis:, chronic pain, metastasis, and Paget's disease.~6. The subject received any investigational medication within 30 days prior to the first dose of study medication.~7. The subject has any known laboratory abnormality, which in the opinion of the investigator, would contraindicate study participation ≧1.5 times the upper limit of the normal reference range.~8. The subject has an active malignancy of any type, or history of a malignancy (Subjects who have a history of basal cell carcinoma that has been successfully treated can be entered into the study.~9. Subject had any condition, which could preclude use of NSAIDs or COX-2 specific inhibitors.~10. The subject has active or suspected esophageal, gastric, pyloric channel, or duodenal ulceration history.~11. The subject has received warfarin or other anticoagulants during the 30 days preceding the first dose of study medication.~12. Subject is anticipated to require or requires treatment with lithium.~13. Subject is American Society of Anesthesiologists(ASA) grade 4-5.~14. The subject has a history of a psychiatric disorder requiring new or changing treatment~15. The subject has a history of uncontrolled chronic disease or a concurrent clinically significant illness, medical condition.~16. The subject has any cognitive impairment or other characteristics that would in the investigator's opinion preclude study participation or compliance with protocol mandated procedures.~17. Subject has a history of asthma or bronchospasm, which requires treatment with glucocorticoids.~18. Subject had a history of alcohol, analgesic or narcotic abuse.~19. Subject has been previously randomized into the study~20. Subjects who are investigational site staff members or relatives of those site staff~21. Participation in other studies within 3 months before the current study begins and/or during study participation~22. Other severe acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation.~23. Pregnant females, breastfeeding females, or males and females of childbearing potential not using effective contraception.~    -

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 90 Years
- Healthy Volunteers: f

Study Arms:
- Parecoxib and Celecoxib (Type: EXPERIMENTAL): Patients in the study group are supplied sequential treatment with Parecoxib 40 mg intravenously (IV) twice daily (Q12h) for the first 3 days post-surgery followed by Celecoxib 200mg orally twice daily (Q12h) up to 6 weeks post-surgery.~Patient-controlled intravenous analgesia (PCIA) with Morphine is administrated to all the subjects starting immediately post-anesthesia and ending at 24h after operation. As long as oral intake is feasible, both the two groups may receive centrally-acting analgesic Tramadol Hydrochloride Sustained release tablets (TRAMCONTIN) as rescue analgesia if VAS score≧3.
- placebo (Type: PLACEBO_COMPARATOR): Patients in the control group are supplied with the corresponding placebo with the same instructions.~Patient-controlled intravenous analgesia (PCIA) with Morphine is administrated to all the subjects starting immediately post-anesthesia and ending at 24h after operation. As long as oral intake is feasible, both the two groups may receive centrally-acting analgesic TRAMCONTIN (Tramadol Hydrochloride Sustained release tablets) as rescue analgesia if VAS score≧3.

Based on this trial design, predict the completion outcome and termination type (if applicable).