Assessed solicited local symptoms were pain, redness and swelling. Any = occurrence of the symptom regardless of intensity grade. Grade 3 pain = Significant pain at rest, pain that prevented normal activity. Grade 3 redness/swelling = redness/swelling with a maximum diameter greater than 100 millimeters (mm).

Assessed solicited general symptoms (symp.) were headache, fever \[defined as oral temperature (temp.) equal to or above 37.5 degrees Celsius (°C)\], fatigue, gastrointestinal (Gastro.) symptoms \[nausea, vomiting, diarrhoea and/or abdominal pain\]. Any = occurrence of the symptom regardless of intensity grade and relationship. Grade 3 (G3) symptom = symptom that prevented normal activity. Grade 3 fever = fever \> 39.5 °C. Related = symptom assessed by the investigator as related to the vaccination.

An unsolicited AE covers any untoward medical occurrence in a clinical investigation subject temporally associated with the use of a medicinal product, whether or not considered related to the medicinal product and reported in addition to those solicited during the clinical study and any solicited symptom with onset outside the specified period of follow-up for solicited symptoms. "Any" was defined as the occurrence of any unsolicited AE regardless of intensity grade or relation to vaccination.

Serious adverse events (SAEs) assessed include medical occurrences that result in death, are life-threatening, require hospitalization or prolongation of hospitalization or result in disability/incapacity.

RSV-A neutralizing antibody titres, expressed as Geometric Mean Titres (GMTs). Seropositive subjects were defined as subjects whose antibody titre was greater than or equal to (≥) the cut-off 8 serum dilution that induced 60 % inhibition in plaque forming units (ED60).