Please assess the completion status of the following clinical trial:

Trial Title: Efficacy and Safety of Vildagliptin as add-on Therapy to Metformin in Patients With Type 2 Diabetes

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

Eligibility Criteria:
Inclusion Criteria:~* Patients with type 2 diabetes inadequately controlled with diet, exercise and oral anti-diabetic therapy.~* HbA1c in the range of 7.0-10.0%~* Body mass index in the range 20-35 kg/m2~Exclusion Criteria:~* Type 1 diabetes, diabetes resulting from pancreatic injury, or secondary forms of diabetes~* Significant heart diseases~Other protocol-defined inclusion/exclusion criteria may apply

- Gender: ALL
- Minimum Age: 20 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Vildagliptin (Type: EXPERIMENTAL): In addition to their stable dose of metformin monotherapy, patients should take vildagliptin 50 mg twice daily.
- Placebo (Type: PLACEBO_COMPARATOR): In addition to their stable dose of metformin monotherapy, patients should take vildagliptin matching placebo.

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