Jacob Puliyel2014 Apr 04 3:26 p.m. edited
MINISCULE RISK REDUCTION MAKES $1 ROTAVIRUS VACCINE (116E) UNECONOMICAL IN INDIA
The authors must be congratulated for this study and the candid reporting of the absolute risk reduction (ARR) and numbers needed to treat (NNT).
LOW DISEASE BURDEN
Although rotavirus vaccine efficacy is lower in developing countries, it is advocated for poor countries because of the higher disease burden. Severe rotavirus gastroenteritis (SRVGE) was more common in Malawi than South Africa (13.1 vs. 5.4) and even though efficacy was lower in Malawi (49.4% vs. 76.9%) more cases of SRVGE were prevented by vaccination (6.7 vs. 4.2) Madhi SA, 2010. This is often given as the justification for using the vaccine with such low efficacy in poor countries.
The incidence SRVGE was low very low in the unvaccinated in India (3.4%) compared to 13.1 in Malawi and 5.4 in South Africa. This raises questions about the need for the vaccine in India using the ‘disease burden’ argument.
The absolute risk reduction (ARR) by vaccination was small (1.7). This is much lower than the benefit in Malawi (6.7) and even South Africa (4.2) Madhi SA, 2010.
The NNT was 55. At $3/child, vaccination will cost $ 165 per SRVGE avoided. This is four times the societal cost of hospitalized diarrhea in India ($40.60) Mendelsohn AS, 2008
RISK OF INTUSSUSCEPTIONS
Intussusceptions are more dangerous in developing countries where facilities for its diagnosis and treatment are not easily available in remote areas. The earlier rotavirus vaccine RotaShield had been approved after clinical trials involving 10,054 children. It was then withdrawn from the market for causing intussusceptions (1 in 12,000 children).
After the RotaSheild fiasco, FDA approval of RotaTeq based on results of three phase III trials of the drug which treated a combined 72,324 infants in 11 countries.
The 116E has been studied in only 4532 with 2187 controls (total 6719). This is grossly inadequate for studying safety of this drug. The authors seem to suggest that this small study is sufficient for licensing the drug and safety can be examined during post marketing surveillance! It will indeed be a very brave licensing authority who, based on this study of 6719 children, will license the drug in countries like India where active post marketing surveillance is non-existent and where there is no proper ‘VAERS-like’ system available. In this context Paul King has proposed an effective system for AEFI surveillance with meaningful penalties for any healthcare provider's failure to report any possible AEFI to those maintaining this AEFI database.
Perhaps those keen on the roll out of the vaccine may put such a system in place and some good may come from this vaccine.
Saurabh Kumar, Jacob Puliyel