Please assess the completion status of the following clinical trial:

Trial Title: Glycine Supplement for Severe COVID-19

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

Eligibility Criteria:
Inclusion Criteria:~* Any age.~* Any sex.~* With COVID-19 confirmed (or awaiting confirmation) by PCR.~* With a clinical decision of initiation of mechanical ventilation or with \<48 h under mechanical ventilation.~* Informed consent signed by the participant's responsible.~Exclusion Criteria:~* Pregnant women.~* Already participating in another research protocol.~Elimination Criteria:~* Voluntary hospital discharge or referenced to another institution.

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

Study Arms:
- Glycine (Type: EXPERIMENTAL): Along with habitual treatment for their severe condition, participants will receive 0.5 g/kg/day glycine by nasogastric tube, divided in four equal doses in a day, since their enrollment and until they are weaned from mechanical ventilator or die.
- Control (Type: NO_INTERVENTION): Participants will receive the habitual treatment for their severe condition.

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