Please assess the completion status of the following clinical trial:

Trial Title: Metformin and Longevity Genes in Prediabetes

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

Eligibility Criteria:
Inclusion Criteria:~* Pre-diabetes, defined as IFG (fasting glucose between 100 and 125 mg/dl) or IGT (2h post-oral glucose load (75g) between 140 and 199 mg/dl);~* Age 40-75 years;~* Both genders.~Exclusion Criteria:~* Type 1 or 2 diabetes mellitus;~* Pregnancy, lactation;~* Acute, chronic or inflammatory diseases;~* Neoplasms;~* Immunological diseases, organ transplantation, steroid therapy;~* Uncontrolled arterial hypertension (systolic pressure \> 180 mmHg or diastolic \> 120 mmHg);~* Recent(within 3 months) surgical intervention or cardiovascular accidents;~* Known allergy to metformin.

- Gender: ALL
- Minimum Age: 40 Years
- Maximum Age: 75 Years
- Healthy Volunteers: f

Study Arms:
- Metformin (Type: EXPERIMENTAL): Metformin tablets 500 mg tid for 2 months
- Placebo (Type: PLACEBO_COMPARATOR): Placebo tables tid for 2 months

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