Please assess the completion status of the following clinical trial:

Trial Title: Memantine Therapy for Multiple Sclerosis

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: CROSSOVER
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: DOUBLE
- Phase: PHASE2
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Patients with MS (McDonald 2002), both sex, age between 18 to 60 years old, all MS subtypes (RR, SP, PP, PR), stable.~* Patients with severe cognitive impairment defined as performing 1.5 SD below control group (matched by age and education) in 2 o more subtests based in our previous study (Sepulcre 2006):~Exclusion Criteria:~* Psychiatric diseases (Cummings) depression (Hamilton \>8), drug or alcohol abuse, benzodiazepine therapy or other medical diseases.

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 65 Years
- Healthy Volunteers: f

Study Arms:
- A (Type: ACTIVE_COMPARATOR): Memantine 30 mg/day
- B (Type: PLACEBO_COMPARATOR): Placebo

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