Please assess the completion status of the following clinical trial:

Trial Title: Evaluation of Immunogenicity and Safety of Combined Immunization of COVID-19 Vaccine (Produced in Beijing) and PPV23 / IIV4

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: PREVENTION
- Time Perspective: None
- Masking: SINGLE
- Phase: PHASE4
- Number of Arms: 3.0

Eligibility Criteria:
Inclusion criteria:~* ≥18 years old when enrolled;~* Participants signing the informed consent;~* Being able to participate in all planned follow-ups and accomplish all research procedures including completing a diary card and coming back for interview;~* Having not been administered any pneumonia vaccine or COVID-19 vaccine, and having not been administered an influenza vaccine in the current season before enrollment;~* ≥14 days from the most recent vaccination;~* Before enrollment, the body temperature is ≤37.0C as confirmed by medical history and clinical examination.~Exclusion criteria for the first dose:~* Having a history of COVID-19 or a positive nucleic acid test for COVID-19;~* Having a history or a family history of allergy, convulsion, epilepsy, brain disease, or mental illness;~* Being allergic to any component of vaccines, or having a history of severe allergic reaction to any vaccine;~* Having immunodeficiency disorder, during treatment of malignant tumor, having immunodeficiency induced by immunosuppressants (oral steroid hormones) or HIV, or having a family member with close contact who suffers from congenital immune disorder;~* Having injection of non-specific immunoglobulin within 1 month prior to enrollment;~* Having acute febrile illness or communicable disease;~* Having a history of confirmed thrombocytopenia or other coagulation disorders, which may cause contraindications for a subcutaneous injection;~* Having severe chronic disease or acute exacerbation of chronic disease, or having uncontrolled hypertension or diabetes;~* Having various infectious, pyogenic, or allergic skin diseases;~* Women in pregnancy or lactation or participants who plan for a baby within 3 months after vaccination should delay the vaccination;~* Having any condition that may affect trial assessment as determined by researchers.~Exclusion criteria for the second dose:~* Having any serious adverse event related to the first dose vaccination;~* After vaccination, having systemic adverse reaction or allergic reaction with a severity of grade 3 or higher as determined by researchers;~* Having a newly emerging condition that meets the exclusion criteria for the first dose;~* Having any condition that may affect trial assessment as determined by researchers.

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

Study Arms:
- Experimental group (Type: EXPERIMENTAL): Experimental Group (384 subjects) will receive: 1st dose : combined vaccination of COVAX+IIV4; 2nd dose: combined vaccination of COVAX+PPV23
- Control group A (Type: ACTIVE_COMPARATOR): Control Group A (384 subjects) will receive: 1st dose: COVAX only; 2nd dose: COVAX only
- Control group B (Type: ACTIVE_COMPARATOR): Control Group B (384 subjects) will receive: 1st dose: IIV4 only; 2nd dose: PPV23 only

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