Please assess the completion status of the following clinical trial:

Trial Title: A Study of Ad26.COV2.S for the Prevention of SARS-CoV-2-mediated COVID-19 in Adults

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

Eligibility Criteria:
Inclusion Criteria:~* Contraceptive (birth control) use should be consistent with local regulations regarding the acceptable methods of contraception for those participating in clinical studies~* All participants of childbearing potential must: have a negative highly sensitive urine pregnancy test at screening; and have a negative highly sensitive urine pregnancy test immediately prior to each study vaccine administration~* Participant agrees to not donate bone marrow, blood, and blood products from the first study vaccine administration until 3 months after receiving the last dose of study vaccine~* Must be willing to provide verifiable identification, has means to be contacted and to contact the investigator during the study~* Must be able to read, understand, and complete questionnaires in the electronic clinical outcome assessment (eCOA) (that is, the coronavirus disease-2019 \[COVID 19\] signs and symptoms surveillance question, the e-Diary, and the electronic patient-reported outcomes (ePROs)~Exclusion Criteria:~* Participant has a clinically significant acute illness (this does not include minor illnesses such as diarrhea or mild upper respiratory tract infection) or temperature greater than or equal to (\>=) 38.0 degree Celsius (100.4-degree Fahrenheit) within 24 hours prior to the planned first dose of study vaccine; randomization at a later date is permitted at the discretion of the investigator and after consultation with the sponsor~* Participant has a known or suspected allergy or history of anaphylaxis or other serious adverse reactions to vaccines or their excipients~* Participant received or plans to receive: (a) licensed live attenuated vaccines - within 28 days before or after planned administration of study vaccine; and (b) other licensed (not live) vaccines - within 14 days before or after planned administration of study vaccine~* Participant previously received a coronavirus vaccine~* Participant received an investigational drug within 30 days (including investigational drugs for prophylaxis of COVID-19) or used an invasive investigational medical device within 30 days or received investigational immunoglobulin (Ig) or investigational monoclonal antibodies within 3 months, or received convalescent serum for COVID-19 treatment within 4 months or received an investigational vaccine (including investigational Adenoviral-vectored vaccines) within 6 months before the planned administration of the first dose of study vaccine or is currently enrolled or plans to participate in another investigational study during the course of this study

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: None
- Healthy Volunteers: t

Study Arms:
- Ad26.COV2.S (Type: EXPERIMENTAL): Participants will receive intramuscular (IM) injection of Ad26.COV2.S vaccine on Day 1 and Day 57 in the double-blind phase. At unblinding visit (open-label phase), participants who have not yet received second vaccination will receive second dose of Ad26.COV2.S vaccine on Day 57, if applicable and newly enrolled participants will either receive IM injection of one dose of Ad26.COV2.S vaccine on Day 1 or two doses of Ad26.COV2.S vaccine on Day 1 and Day 57. All ongoing participants who only received a single vaccination with Ad26.COV2.S in the study will be offered to receive single booster dose of Ad26.COV2.S in the open label phase preferably within 6 to 12 months after the participant's first Ad26.COV2.S vaccination.
- Placebo (Type: PLACEBO_COMPARATOR): Participants will receive IM injection of placebo on Day 1 and Day 57 in the double-blind phase. At unblinding visit (open-label phase), participants initially receiving placebo will be offered to receive IM injection of a single dose of Ad26.COV2.S vaccine. All ongoing participants who only received a single vaccination with Ad26.COV2.S in the study will be offered to receive single booster dose of Ad26.COV2.S in the open label phase preferably within 6 to 12 months after the participant's first Ad26.COV2.S vaccination.

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

Answer: outcome: complete