Please assess the completion status of the following clinical trial:

Trial Title: Safety and Efficacy of Natalizumab in Combination With Avonex in the Treatment of Multiple Sclerosis

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

Eligibility Criteria:
Inclusion Criteria:~* Diagnosis of MS as defined by McDonald et al, criteria, # 1- 4~* Between the ages of 18 and 55, inclusive~* Baseline EDSS score between 0.0 and 5.0, inclusive~* Have been treated with Avonex for at least the 12 months prior to randomization~* Have experienced at least one relapse (while on Avonex) within the 12 months prior to randomization.~* Cranial MRI scan demonstrating lesions consistent with MS.~* Have given written informed consent to participate in the study.~Exclusion Criteria:~* Primary progressive, secondary progressive, or progressive relapsing MS.~* MS relapse has occurred within 50 days of randomization~* A clinically significant infectious illness within 30 days prior to randomization~* History of, or abnormal lab result, indicative of significant disease, that in the opinion of the investigator, would preclude the administration of a recombinant humanized antibody immunomodulating agent or Avonex for 116 weeks.~* History of severe allergic or anaphylactic reactions or known drug hypersensitivity.~* Unable to perform the Timed 25-Foot Walk, 9HPT and PASAT 3~* Abnormal blood tests at Screening Visit

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 55 Years
- Healthy Volunteers: f

Study Arms:
- Group 1 (Type: EXPERIMENTAL): Adding natalizumab monthly infusion to Avonex weekly injection for up to 116 weeks.
- Group 2 (Type: PLACEBO_COMPARATOR): Adding placebo monthly infusion to Avonex weekly injection for up to 116 weeks.

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