Phase IIb Trial of Recombinant Novel Coronavirus Vaccine (Adenovirus Type 5 Vector) (Ad5-nCoV) in Adults 18 Years of Age and Older.

Inclusion Criteria:

1. Adults of 18 years of age, and older.

2. Confirmed HIV infection

- At least two HIV plasma viral load (pVL) below 40 copies in the last 12 months,
one within the last 60 days (value obtained at Screening visit can be used for
the value within the last 60 days)

- A CD4 count at screening equal or above 300 cells/mL and a CD4 percentage equal
or above 15 % within the previous 60 days (value obtained at Screening visit
can be used for the value within the last 60 days)

- Participant must be on a stable highly active anti-retroviral treatment (HAART)
for 6 months (unless the change is due to tolerability, in which case the
regimen can be for only the previous 3 months) and with an estimated adherence
of ≥80% within the last 60 days. - A HAART regimen (as defined by the
Argentinean ART guidelines), means a combination of 2 NRTIs plus one INSTI or a
NNRTI or a boosted PI or a dual combination of dolutegravir and 3TC.

3. Able and willing (in the Investigator's opinion) to comply with all study
requirements.

4. Willing to allow the investigators to discuss the volunteer's medical history with
their General Practitioner/personal doctor and access all medical records when
relevant to study procedures.

5. Healthy adults, or stable-healthy adults who may have a pre-existing medical
condition that does not meet any exclusion criteria. A stable medical condition is
defined as disease not requiring significant change in therapy or hospitalization
for worsening disease during the 3 months before enrollment.

6. For females of childbearing potential only, willingness to practice continuous
effective contraception (see glossary) for 30 days prior to enrollment in the study,
for 90 days after receiving vaccination during the study, and have a negative
pregnancy test on the day(s) of screening/ vaccination (First Injection Visit and
Second Injection Visit).

7. Males participating in this study who are involved in heterosexual sexual activity
must agree to practice adequate contraception (see glossary) and refrain from
donating sperm for 90 days after receiving the study vaccination.

8. Agreement to refrain from blood donation during the study.

9. Provide written informed consent.

Exclusion Criteria:

-

1. Participation in any other COVID-19 prophylactic drug trials for the duration
of the study.

Note: Participation in COVID-19 treatment trials is allowed in the event of
hospitalization due to COVID-19. The study team should be informed as soon as possible.
2. Participation in SARS-CoV-2 serological surveys where participants are informed of
their serostatus for the duration of the study.

Note: Disclosure of serostatus post enrolment may accidentally unblind participants to
group allocation. Participation in this trial can only be allowed if volunteers are kept
blinded to their serology results from local/national serological surveys 3. Planned
receipt of any vaccine (licensed or investigational), other than the study intervention,
within 14 days before and after study vaccination 4. Prior receipt of an investigational
or licensed vaccine likely to impact on the interpretation of the trial data (e.g.
Adenovirus vectored vaccines, any coronavirus or SARS vaccines) 5. Administration of
immunoglobulins and/or any blood products within the three months prior to the planned
administration of the vaccine candidate 6. Any confirmed or suspected immunosuppressive
or immunodeficient state (other than living with HIV, on stable treatment, and
virologically suppressed for at least 6 months); asplenia; recurrent severe infections
and chronic use (more than 14 days) of immunosuppressant medication within the past 6
months. Topical steroids or short-term (course lasting ≤14 days) oral steroids are not an
exclusion 7. Active opportunistic infections or other AIDS-defining illness in the last
six months.

8. History of allergic disease or reactions likely to be exacerbated by any component
of Ad5-nCoV 9. Any history of angioedema 10. Any history of anaphylaxis to any
vaccine component 11. Pregnancy, lactation or willingness/intention to become
pregnant within 90 days after receiving study vaccine 12. Current diagnosis of or
treatment for cancer (except basal cell carcinoma of the skin and cervical carcinoma
in situ) 13. History of serious psychiatric condition likely to affect participation
in the study 14. Bleeding disorder (e.g. factor deficiency, coagulopathy or platelet
disorder), or prior history of significant bleeding or bruising following IM
injections or venepuncture 15. Suspected or known current alcohol or drug dependency
16. Severe and/or uncontrolled cardiovascular disease, respiratory disease,
gastrointestinal disease, liver disease, renal disease, endocrine disorder and
neurological illness (mild/moderate well-controlled comorbidities are allowed) 17.
History of laboratory-confirmed COVID-19 18. Continuous use of anticoagulants, such
as coumarins and related anticoagulants (i.e. warfarin) or novel oral anticoagulants
(i.e. apixaban, rivaroxaban, dabigatran and edoxaban) 19. Any other significant
disease, disorder or finding which may significantly increase the risk to the
volunteer because of participation in the study, affect the ability of the volunteer
to participate in the study or impair interpretation of the study data.