A vaccine must be licensed first by the appropriate authority for the use
in the country. The vaccines/drugs licensing authority in India, i.e.
National Regulatory Authority (NRA) is Drugs Controller General of India (DCGI)
which is approved by WHO also. For licensing of a new vaccine, the vaccine
manufacturer should conduct the phase I, II, and III trials and must
submit their results to NRA for its approval.
There are both central and state licensing authorities.
Good clinical practice (GCP) and ethical guidelines (by ICMR) for approval
exist. Licensing of products in India is by the Central Licensing Approval
Authority (CLAA). The Drug Technology Advisory Board (DATB) approves
introduction of vaccines into the immunization services, while all vaccine
approval and clinical trials is by the CLAA. The state licensing authority
inspects and grants licensing for retail.
Imported products are considered on a case-by-case
basis; if trials meet the requirements of the NRA, there is no insistence
on clinical trials in the country for registration. The advisory
committees that review the information follow published guidelines,
directed by a responsible person. External clinical experts may be asked
for advice on a case-by-case basis.
After licensing, the vaccine manufacturer should
undertake a large post-marketing surveillance (Phase IV) to further ensure
the safety of their products. Any complaint regarding the safety,
efficacy, etc of the licensed vaccine should be directed to NRA. Once the
vaccine is licensed in the country, it can be used both by the private as
well as the public sector. All the vaccines recommended by IAP-COI are
approved by WHO.
The combining of multiple related or unrelated antigens
into a single vaccine is not a new concept. Several combination vaccines
have been in use including the trivalent influenza accines, diphtheria,
pertussis and tetanus toxoids (DTwP, DTaP, DT, Td, Tdap), the polio
vaccines, MMR and meningococcal vaccines. Additionally, several other
multivalent vaccines have been recently introduced including the
pneumococcal, rotavirus and HPV vaccines.
The advantages of combination vaccines are multiple and
include fewer injections, reduced burden on the cold chain, reduced
requirement of syringes and needles, and easier record keeping. However,
the concerns and fears of stability of the new combination products and
immune interference between the various antigens leading to suboptimal
immunogenicity have been raised by many but so far do not have much basis
and for all practical purposes each individual constituent does have
equally protective efficacy as when given separately. Furthermore, the
combination vaccines are also treated like any other new vaccine and they
also need to undergo the same process of clinical trials and licensing as
applicable to a new vaccine.
