Pneumococcal Disease

The purpose of this study is to learn about the safety of a new pneumococcal vaccine and how the new pneumococcal vaccine helps to fight against germs that can cause pneumonia (lung infections), meningitis (brain infections), and otitis media (ear infections) in children when compared to the pneumococcal vaccine that is currently in use, 20vPnC (Prevnar 20®). This study will test if the new pneumococcal vaccine is as safe as the one that is currently in use. It will also assess how the new vaccine works in comparison to the one that is currently in use. To measure how the new pneumococcal vaccine compares to the current one, blood samples will be used to measure the body's ability to create proteins to fight those germs. This new vaccine can possibly provide additional protection against germs that cause pneumococcal disease that are not included in the vaccines that are currently given to children. Pneumococcal disease includes a variety of infections caused by a specific germ, Streptococcus pneumoniae This study is seeking participants who: * Are children aged 15 months to 18 years. * May or may not have received any doses of pneumococcal conjugate vaccine (PCV) in the past. The study will be conducted in the United States, Puerto Rico, and other countries. Participants will be assigned to 1 of 3 groups based on age: Group 1: 15 months to less than 2 years (about 300 participants) Group 2: 2 years to less than 5 years (about 300 participants) Group 3: 5 years to less than 18 years (about 600 participants) Within each group, participants will be assigned by chance in a 2:1 ratio to receive 1 vaccine injection (shot) with either PG4 (new vaccine) or 20vPnC, given in the arm or thigh. This means that for every 3 participants, about 2 will receive PG4 and about 1 will receive 20vPnC. Each participant will take part in the study for approximately 6 months. During this time, each participant will visit a clinic 2 times (visit 1 for vaccination and visit 2 to follow up) and will be contacted via telephone once (for a 6 month follow up). At the study clinic visits, participants will have their blood drawn and be asked if they have experienced any side effects. A side effect is an unintentional or unexpected reaction to a vaccine. During the 6-month follow-up contact, participants will be asked about any further side effects.

The purpose of this study is to learn about the safety of a new pneumococcal vaccine and how the new pneumococcal vaccine helps to fight against germs that can cause pneumonia (lung infections), meningitis (brain infections), and otitis media (ear infections) in infants when compared to the pneumococcal vaccine that is currently in use, 20vPnC (Prevnar 20®). This study will test if the new pneumococcal vaccine is as safe as the one that is currently in use. It will also assess how the new vaccine works in comparison to the one that is currently in use when given with other childhood vaccines. To measure how the new pneumococcal vaccine compares to the current one, blood samples will be used to measure the body's ability to create proteins to fight those germs. This new vaccine can possibly provide additional protection against germs that cause pneumococcal disease that are not included in the vaccines that are currently given to infants. Pneumococcal disease includes a variety of infections caused by a specific germ, Streptococcus pneumoniae. There are three groups in this study. All participants will be assigned to one of the three groups. This study is seeking participants who are: * infants who are 2 months of age in Group 1; * infants who are 2 to 6 months of age in Groups 2 and 3; and * said to be healthy by the study doctor About 3000 infants will be assigned to Group 1. The infants in this group will have a 1 in 2 chance (50%) of receiving either PG4 (new vaccine) or 20vPnC (currently in use) into the left thigh muscle at 2, 4, 6, and 12 to 15 months of age. About 140 infants from outside the United States will be assigned to Group 2. The infants in this group will have a 1 in 2 chance (50%) of receiving either PG4 or 20vPnC into the left thigh muscle at 2 to 6, 3 to 8, 4 to 10, and 12 to 15 months of age. About 90 infants from outside the United States will be assigned to Group 3. The infants in Group 3 will have a 1 in 3 chance (33%) of receiving either PG4 into the left thigh muscle, PG4 under the skin of the left thigh, or 20vPnC into the left thigh muscle at 2 to 6, 3 to 8, 4 to 10, and 12 to 15 months of age. Infants in Group 1 will take part in this study for about 16 to 19 months (about 1 and a half years). Infants in Groups 2 and 3 will take part in this study for 12 to 21 months (about 1 to 1 and a half years). During this time, infants will have 6 study clinic visits and 1 phone call. At these study clinic visits, parent(s)/legal guardian(s) will be asked if the infant experienced any side effects. A side effect is an unintentional or unexpected reaction to a vaccine. Infants will have 3 blood samples collected.

The purpose of this study is to learn about the safety of a new pneumococcal vaccine and how the new pneumococcal vaccine helps to fight against germs that can cause pneumonia (lung infections), meningitis (brain infections), and otitis media (ear infections) in infants when compared to the pneumococcal vaccine that is currently in use, 20vPnC (Prevnar 20®). This study will test if the new pneumococcal vaccine is as safe as the one that is currently in use. This new vaccine can possibly provide additional protection against germs that cause pneumococcal disease that are not included in the vaccines that are currently given to infants. Pneumococcal disease includes a variety of infections caused by a specific germ, Streptococcus pneumoniae. There are two groups in this study. All participants will be assigned to one of the two groups. This study is seeking participants who are: \- infants who are about 2 months of age About 2400 infants will be assigned by chance to one of the two groups to receive either PG4 (new vaccine) or 20vPnC (currently in use) into the left thigh muscle at 2, 4, 6, and 12 to 15 months of age. Infants will take part in this study for about 16 to 19 months (about 1 and a half years). During this time, infants will have 6 study clinic visits and 1 phone call. At these study clinic visits, parent(s)/legal guardian(s) will be asked if the infant experienced any side effects. A side effect is an unintentional or unexpected reaction to a vaccine.

The goal of this study is to learn whether different types of vaccines to prevent bacterial infections are able to effectively create antibodies that defend against certain types of bacteria. We will give two different types of vaccine and evaluate the effectiveness of antibodies produced by each vaccine in killing bacteria.

The goal of the OPTIMAL clinical trial is to learn if a dose of a pneumococcal conjugate vaccine (PCV) generates a good immune response in young children who are in hospital with severe acute malnutrition. Researchers will compare an intervention group who get a dose of a PCV (Pneumosil) to a control group who get a dose of a Typhoid conjugate vaccine (Typbar TCV). To ensure all participants receive timely potential benefits, at 3 months participants in the intervention group with receive a dose of Typbar TCV, and those in the conrol group will receive a dose of Pneumosil. Participants will be visited 4 times at their homes over six months after vaccination, with a phone review at 12 months after vaccination.

The study will collect serum from 12 participants vaccinated with Gamma-PN to assist with assay development and validation

Streptococcus pneumoniae (pneumococcus) is a bacterium that causes just under four million serious infections every year. It is normal for pneumococcus bacteria to live in the noses of healthy adults and children as part of the nasal microflora without causing harm. This is called "carriage". But the bacteria can still be passed on to other people. If they are at-risk, for example elderly, or very young, or have pre-existing health conditions, the pneumococcus bacteria can cause pneumonia, which can cause serious life-threatening illness. Pneumococcus bacteria are surrounded by a sugar capsule. But the capsule does not always have the same components. As a result, the bacteria are classified into more than 100 different types. To make them effective, the vaccines that are currently available contain the sugar capsules of the most common pneumococcal types that cause disease. One such vaccine - PCV13 - has been effective globally in protecting against pneumococcus disease. It works because it controls the "carriage" (how a person carries the bacteria in their nose) of 13 types of the bacteria. Vaccines giving protection against other types of the bacteria are also becoming available worldwide. PCV15 is similar to PCV13 and protects against two additional types of the bacteria so may offer more protection. This study, which lasts 2 months and is funded by Merck Sharp \& Dohme (MSD), aims to assess if using PCV15 can protect against "carriage". To do this, investigators will use a well-established method already used with more than 2,000 people safely in other research. This involves "challenging" volunteers by putting a small amount of the pneumococcus bacteria into their noses. In this study, before they are challenged, volunteers will either be vaccinated with the real PCV15 vaccine or a dummy ("placebo"). The Investigators will then be able to compare the two groups to find out who the vaccine protected and who it did not. After the study everyone who takes part and fit into certain criteria will be given antibiotics to clear the pneumococcus colonisation. They will also be regularly monitored during the study to ensure their safety. A very small number of volunteers will be asked to have a biopsy to collect tissue samples from inside their nose before and after being vaccinated with PCV15. This will help researchers to understand more about how the immune system responds to the vaccine. The information gain in this project will help the investigators to understand how exactly PCV15 vaccine protects people against pneumococcus. This means that this vaccine and future pneumococcal vaccines will be improved to protect many lives in future around the world.

This study is a randomized, blinded, parallel controlled phase 3 clinical trial to evaluate the immunogenicity and safety of the 23-valent pneumococcal polysaccharide vaccine in healthy people aged 2 years and above.