What is unique about CaPtivantTM ?

CaPtivantTM calcium phosphate nanoparticle technology should not be confused with the commercially available natural calcium phosphate mineral that has been in use in human vaccines in Europe since 1960s. Other than being a similar (not identical) chemical compound and equally safe for human vaccines, our CaP nanoparticle technology significantly differs from the commercial calcium phosphate with respect to morphology, physicochemical properties, and also mechanisms of adjuvant action in vaccines.


Unlike commercial calcium phosphate, alum, and various other adjuvants in development, CaPtivantTM exhibits properties that appear ideal for development of new vaccines or enhancing immune response to licensed vaccines:

  • Induces systemic and mucosal immune response by injection or mucosal administration
  • Induces higher antigen-specific humoral response than alum or lipid-based adjuvants in most cases
  • Stimulate both Th1- and Th2-type immune responses
  • Induces strong antigen-specific cytotoxic T lymphocyte (CTL) activation
  • Indicates potential for developing not only prophylactic but also therapeutic vaccines
  • Allows formulation of vaccines as stable dry powder
  • Does not stimulate IgE or generate local inflammatory reactions
  • Can also act as a depot for sustained release of Ag and enhances leucocyte recruitment and phagocytic activity of macrophages. 
  • Demonstrates dose sparing properties often leading to the use of lower vaccine dosage while offering improved safety profiles.

CaPtivate's CaP Nanoparticles
Commercial Calcium Phosphate
initially developed by Pasteur Institute in France

    Why Consider CaPtivantTM in Vaccines Development ?


  • Contains all GRAS components, is non-toxic, biodegradable, and biocompatible
  • Acute toxicity studies in Guinea pigs; no toxicity by injection routes, pulmonary, intranasal, or oral administration.
  • Safety and toxicity study in Phase I human clinical trial completed; no toxicity by injection
  • It is manufactured using cost-effective, standardized, high-yield, scalable, and flexible processes to produce particles in less than 100 nm to micrometer ranges
  • Process has been scaled up under cGMP
  • Is stable for many years when stored at room temperature
  • Can be freeze-dried into free-flowing uniform powder which is non-hygroscopic and stable for many years at room temperature
  • Vaccines formulated with CaP remain stable when exposed to freeze/thaw conditions
  • Large pre-clinical portfolio exists to demonstrate the safety and efficacy in human and veterinary vaccines
  • Is considered a natural preservative which enhances vaccine stability
  • Contains dose-sparing properties as in-vivo studies indicate that lower antigen doses will be required to achieve desired level of immunity
  • Demonstrates synergistic effects with other adjuvants
  • Vaccines containing CaP should face minimum regulatory challenges going into clinical trials