Please assess the completion status of the following clinical trial:

Trial Title: A Study to Evaluate the Safety, Reactogenicity, and Immunogenicity of Adenovirus Serotype 26 Based Respiratory Syncytial Virus Pre-fusion (Ad26.RSV.Pre-F) Vaccine in RSV-Seronegative Toddlers 12 to 24 Months of Age

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

Eligibility Criteria:
Inclusion Criteria:~* Participant who is seronegative for respiratory syncytial virus (RSV) within 42 days prior to dosing~* Participant is the product of a normal term pregnancy greater than or equal to (\>=)37 weeks, with a minimum birth weight of 2.5 kilogram (kg)~* Participant must be in good health without any significant medical illness on the basis of physical examination, medical history, and vital signs performed at screening~* Participant has received all routine immunizations appropriate for his or her age according to local guidelines~* Each participant's parent(s)/legal guardian(s) must have access to a consistent means of contact either by telephone contact or email/computer~Exclusion Criteria:~* Participant's weight is below tenth percentile according to World Health Organization (WHO) pediatric growth and weight charts~* Participant has any clinically significant acute or chronic medical condition (for example, history of seizure disorders, bleeding/clotting disorder, autoimmune disease, active malignancy, systemic infections, congenital heart disease, history of any pulmonary condition requiring medication, atopy, reactive airway disease, medically-confirmed wheezing, bronchoconstriction or treatment with a beta 2 agonist, cystic fibrosis, bronchopulmonary dysplasia, chronic pulmonary disease, medically-confirmed apnea, hospitalization for respiratory illness, or mechanical ventilation for respiratory illness) that, in the opinion of the investigator, would preclude participation~* Participant is in receipt of, or planning to receive, live attenuated vaccine (for example, measles, mumps and rubella \[MMR\] or varicella, but excluding rotavirus vaccine) within 28 days of each study vaccination (that is, before and after); other vaccines (for example, influenza, pertussis, polio or rotavirus) should be given at least 14 days before or 14 days after each study vaccination~* Participant has known or suspected immunodeficiency, such as known human immunodeficiency virus (HIV) infection~* Participant has a known allergy to vaccines or vaccine components (including any of the constituents of the study vaccine), or history of anaphylaxis or other serious adverse reactions to vaccines or vaccine components (including any of the constituents of the study vaccine). Participants with egg allergies can be enrolled

- Gender: ALL
- Minimum Age: 12 Months
- Maximum Age: 24 Months
- Healthy Volunteers: t

Study Arms:
- Group 1: RSV Seronegative Toddlers (Ad26.RSV.preF) (Type: EXPERIMENTAL): Respiratory syncytial virus (RSV) seronegative toddlers will receive intramuscular (IM) injection of 2.5\*10\^10 viral particles (vp) of an adenovirus serotype 26- based vaccine encoding for the respiratory syncytial virus pre-fusion F-protein on Days 1, 29, and 57.
- Group 2: RSV Seronegative Toddlers (Placebo/Nimenrix) (Type: PLACEBO_COMPARATOR): RSV seronegative toddlers will receive IM injection of placebo on Days 1, 29 and 57. Placebo can be replaced with Nimenrix on Day 57 in countries where applicable.

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