Haemophilus influenzae type b polyribosylribitol phosphate-tetanus toxoid conjugate (PRP-T) (PRP-T)

Haemophilus influenzae type b polyribosylribitol phosphate (PRP) conjugated to tetanus protein is a semi-synthetic antigen used in vaccines to prevent invasive Hib infections [StatPearls, 2023]. The PRP component is the capsular polysaccharide of the bacterium, which serves as the primary target for protective antibodies [CDC, 2022]. Because pure polysaccharides are T-cell independent antigens, they fail to induce a robust immune response or memory in infants whose immune systems are immature [WHO, 2013]. Conjugation to a tetanus toxoid carrier protein transforms the PRP into a T-cell dependent antigen, enabling the recruitment of T-helper cells [PubMed, PMID: 12758155]. This process facilitates B-cell isotype switching and the development of high-affinity IgG antibodies and long-term memory cells [FDA, 2023]. Consequently, this conjugate is highly effective in protecting young children against life-threatening conditions like bacterial meningitis, epiglottitis, and pneumonia [StatPearls, 2023]. The vaccine is typically administered in a multi-dose series starting at two months of age to ensure sustained protection during the period of highest vulnerability [CDC, 2022]. The use of this conjugate has led to a dramatic reduction in the global incidence of Hib-related morbidity and mortality [WHO, 2013].

Other names

Hib-TPRP-THaemophilus b Conjugate Vaccine (Tetanus Toxoid Conjugate)Polyribosylribitol phosphate-tetanus toxoid

Induces active immunity against Haemophilus influenzae type b by stimulating the production of anti-PRP IgG antibodies through a T-cell dependent pathway [StatPearls, 2023].