Please assess the completion status of the following clinical trial:

Trial Title: A Study in China Evaluating the Safety and Efficacy of Adding Sitagliptin to Stable Therapy With Insulin With or Without Metformin in Participants With Type 2 Diabetes Mellitus (T2DM) (MK-0431-254)

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: TRIPLE
- Phase: PHASE3
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* has T2DM~* is currently on a stable regimen of pre-mixed, intermediate-acting, or long-acting insulin at a dose of at least 12 U/day, either alone or in combination with metformin \>=1500 mg/day for ≥ 10 weeks~* has a Visit 1/Screening HbA1C between 7.5% and 11.0%~* is a male, or a female who is highly unlikely to conceive during the study and for 14 days after the last dose of study medication~Exclusion Criteria:~* has been treated with any antihyperglycemic therapies other than a protocol-required insulin (alone or with metformin) within the prior 12 weeks or has ever~been treated with a dipeptidyl peptidase-4 inhibitor or a glucagon-like peptide-1 mimetic or analogue~* is currently on treatment with daily use (one or more injections per day) of~pre-prandial short-acting or rapid-acting insulin~* has a history of 2 or more episodes of hypoglycemia resulting in seizure,~coma, or loss of consciousness, or has had recurrent episodes of hypoglycemia over the past 8 weeks~* has a history of intolerance or hypersensitivity, or has any contraindication to sitagliptin, insulin, or metformin~* is on a weight loss program and not in the maintenance phase, or has started a weight loss medication or has undergone bariatric surgery within 12 months~* has undergone a surgical procedure within 4 weeks or has planned major surgery during the study~* has a medical history of active liver disease~* has had new or worsening signs or symptoms of coronary heart disease within the past 3 months, or has acute coronary syndrome, coronary artery intervention, or stroke or transient ischemic neurological disorder~* has a diagnosis of congestive heart failure with New York Heart Association Class III - IV cardiac status~* has a systolic blood pressure ≥ 160 mmHg or a diastolic blood pressure ≥ 90 mmHg~* has human immunodeficiency virus (HIV)~* has severe peripheral vascular disease~* is currently being treated for hyperthyroidism or is on thyroid hormone therapy and has not been on a stable dose for at least 6 weeks~* has a history of malignancy ≤ 5 years before the study, except for adequately treated basal cell or squamous cell skin cancer, or in situ cervical cancer~* has a clinically important hematological disorder (such as aplastic anemia,~myeloproliferative or myelodysplastic syndromes, thrombocytopenia)~* is pregnant or breast feeding, or is expecting to conceive or donate eggs during the study, including 14 days after the last dose of study medication~* is a user of recreational or illicit drugs or has had a recent history of drug abuse

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 79 Years
- Healthy Volunteers: f

Study Arms:
- Sitagliptin (Type: EXPERIMENTAL): Participants treated with sitagliptin 100 mg, once daily, for 24 weeks. All participants will be under treatment with a stable dose of insulin with or without metformin for ≥10 weeks before and throughout the study. All participants will receive placebo during the Placebo Run-in period.
- Placebo (Type: PLACEBO_COMPARATOR): Participants treated with placebo matching sitagliptin, once daily, for 24 weeks. All participants will be under treatment with a stable dose of insulin with or without metformin for ≥10 weeks before and throughout the study. All participants will receive placebo during the Placebo Run-in period.

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