Please assess the completion status of the following clinical trial:

Trial Title: Metabolic Effects of Metformin Therapy in Obstructive Sleep Apnea

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: PREVENTION
- Time Perspective: None
- Masking: QUADRUPLE
- Phase: PHASE1/PHASE2
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Body mass index (BMI) ≥ 30-50 kg/m\^2 (inclusive).~* Apnea-Hypopnea Index ≥ 15 events/h.~* Must be able to provide written informed consent.~* Willing to participate and adhere to study procedures (video recorded in-lab sleep studies, positive airway pressure (PAP) treatment, take study drug, have adipose tissue and skeletal muscle biopsies).~* Women of child-bearing potential must agree to use appropriate contraception to avoid pregnancy throughout the study.~* Willing to have blood, as well as adipose and muscle tissue stored for future use.~Exclusion Criteria:~* HbA1c \> 6.4%.~* Severe or uncontrolled hypertension defined as systolic blood pressure (BP) ≥180 mmHg and/or diastolic BP ≥110 mmHg on the average of three seated measurements after being at rest for at least 5 minutes.~* Significant cardiovascular, hepatic, renal, neurologic, or psychiatric disease as determined by the study physician.~* Pregnancy, breast feeding or planning pregnancy in the coming 4 months.~* Impaired renal function defined as estimated glomerular filtration rate (eGFR) \<60ml/min/1.73m2 (estimated with Chronic Kidney Disease Epidemiology Collaboration equation 1 method).~* Known hypersensitivity to metformin.~* Currently taking a glucose lowering or weight loss medications.~* Current PAP use or use of PAP in the past 6 months.~* Currently taking antihypertensive and lipid-lowering medications known to affect adipose tissue and skeletal muscle metabolism. For example, statins and drugs targeting renin-angiotensin system will not be allowed. However, use of diuretics, beta-blockers, alpha-blockers and calcium channel blockers may be allowed provided the participant is on a stable dose for at least 3 months prior to the study visit.~* Oxygen desaturation index \<15 events/h of sleep.~* Any medication or condition that, in the opinion of the medical investigator, could interfere with the study outcomes or put the subject at risk by participating in the study.

- Gender: ALL
- Minimum Age: 35 Years
- Maximum Age: 65 Years
- Healthy Volunteers: f

Study Arms:
- Metformin + PAP (Type: EXPERIMENTAL): Subjects randomized to this arm will be orally given 2000 mg metformin daily. Metformin dosage will be slowly increased to improve tolerance.~Subjects will also be provided PAP (positive airway pressure) device for standard management of obstructive sleep apnea.
- Placebo oral capsule + PAP (Type: PLACEBO_COMPARATOR): Subjects randomized to this arm will receive placebo matching study drug. Subjects will also be provided PAP (positive airway pressure) device for standard management of obstructive sleep apnea.

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