To evaluate the Immunogenicity and Safety of Shanghai Institute of Biological Products Co., Ltd.'s Measles, Mumps and Rubella (MMR) Vaccine Compared to a Licensed and WHO Prequalified GSK MMR Vaccine in Healthy African Children, 9-11 Months of Age.

This study is designed as a phase III, multi-center, randomized, observer blind active controlled non-inferiority study, enrolling 1200 healthy African children between the ages of 9-11 months. The enrolled children will be randomized to three groups in the ratio of 1:1:1 (400 children in each group) receiving a single dose of SIBP MMR vaccine alone at 1st dose on D1 and licensed YF vaccine alone at 2nd dose on D43 (Group 1, MMR1YF2) or a single dose of GSK MMR vaccine alone at D1 (Group 2, GSK MMR1) or a single dose of SIBP MMR vaccine co-administered with YF vaccine on D1 (Group 3, MMR1YF1). This study will have an observer-blinded phase for Group 1 and Group 2 followed by an open label phase from Day 43. Group 3 will remain an open label arm throughout the period of the study.

Inclusion Criteria:

• Healthy male and female child as established by medical history and clinical examination at enrollment.
• Age: 9-11 months (inclusive) at the time of enrollment
• Parent's/legally acceptable representative's (LAR) ability to read and willingness to provide written informed consent as per the ethical and regulatory requirements of the site.
• Parent confirms intention to stay in the study area for the study duration, bring their child in for the required study visits or to accept a home visit by the study staff.

Exclusion Criteria:

• Presence of fever (defined as axillary temperature ≥ 37.5°C) (temporary exclusion until recovery)
• Acute disease of moderate to severe intensity at the time of enrollment (temporary exclusion until recovery)
• Use of antipyretics within the last 72 hours prior to enrolment (temporary exclusion until recovery)
• Prior (within 6 months) or concurrent participation in another interventional clinical trial during the study
• Presence of severe malnutrition (weight-for-height z-score < -3SD median)
• Positive test for any of the following: HIV, hepatitis B, hepatitis C and syphilis
• Presence of any systemic disorder (cardiovascular, pulmonary, hepatic, renal, gastrointestinal, hematological (including severe anemia), endocrine, immunological, dermatological, neurological, cancer, or autoimmune disease) as determined by medical history and / or physical examination which would compromise the participant's health or is likely to result in nonconformance to the protocol.
• Known or suspected impairment of immunological function based on medical history and physical examination.
• Prior receipt or intent to receive measles, mumps, rubella, or yellow fever-containing vaccine during the study vaccination and follow up period up to Day 85 outside the study center.
• Receipt of any vaccine (except OPV and inactivated influenza) within 4 weeks of the day of study vaccination or intent to receive any within 6 weeks after study vaccination.
• Receipt of immunoglobulin therapy and / or blood products in the past 9 months or planned administration during the study period
• Receipt of any immune-modifying or immunosuppressant drugs prior to the first study vaccine dose or planned use during the study. A chronic oral or parenteral use (defined as more than 14 days) of high dose corticosteroids (defined as ≥2 mg/kg of body weight or ≥20 mg/day of prednisone or equivalent for persons who weigh >10 kg) will be exclusionary for the study. Children on inhaled or topical steroids may be permitted to participate in the study.
• Evidence of a clinically significant major congenital anomaly or genetic defect as judged by the investigator.
• Any known or suspected bleeding disorder in the participant that would pose a risk to venipuncture or intramuscular injection.
• History of any neurologic disorders including encephalopathy, epilepsy, and other progressive neurological diseases
• A known or suspected sensitivity or allergy to any components of the investigational product including egg, chicken protein and the antibiotic gentamycin.
• History of severe allergic reaction with generalized urticaria, angioedema, or anaphylaxis.
• Any medical condition in the parent/LAR or child which, in the judgment of the Investigator, would interfere with or serves as a contraindication to protocol adherence or a participant's parent(s)'/LAR's ability to give informed consent.

This study will have an observer-blinded phase for Group 1 and Group 2 followed by an open label phase from Day 43. Group 3 will remain an open label arm throughout the period of the study.