This is a randomized, double-blind, placebo-controlled, multicenter, parallel-group
study of the efficacy and safety of 2 weight-based treatment groups of plecanatide
versus placebo in children and adolescent participants 6 to less than 18 years of age with FC. Randomization will be stratified by sex to ensure balance across treatment groups.

Approximately 30 participants will be randomized to each of the Placebo, Low
Dose, and High Dose groups, within age group. Low Dose and High Dose will be
assigned once daily treatments based on the weight of the participant at
randomization to achieve weight-based dosing of 0.025 to 0.05 mg/kg in the Low
Dose treatment group and 0.05 to 0.1 mg/kg in the High Dose treatment group.

This trial is testing V118C in infants and toddlers.

V118C is an experimental vaccine. Vaccines help to prevent illness by teaching the body's immune system how to fight infections. The immune system is a network of organs and cells that fight infections. If it works, V118C may prevent an illness called pneumococcal disease. This is an illness caused by certain germs. These germs can cause infections, some of which may be serious, in the ears, nose, lungs, blood, or brain.

This trial will compare V118C to a vaccine called PCV20. PCV20 is approved to prevent pneumococcal disease in infants and toddlers.

The flu is caused by a virus that can sometimes change. This can make the flu resistant to treatment, which means drugs, like baloxavir marboxil, can become less effective for treating the flu (also known as "resistance").

The purpose of this study is to monitor changes in the flu virus before and after study treatment with baloxavir marboxil in children. The resistance of the flu virus to study treatment with baloxavir marboxil will also be monitored.

The investigational varicella vaccine (hereafter referred to as VNS vaccine) is a new
candidate varicella vaccine derived from the Oka strain. The main rationale for the
development of VNS vaccine is to provide an additional alternative varicella vaccine as an advantage from a public health perspective to prevent varicella disease