India will have to expand its collaboration for rapidly rolling out Covid vaccines as it faces dual daunting tasks of vaccinating its billion-plus population as well as fulfilling its vaccine diplomacy, views Dr Ankan Gupta, Scientist, Department of Pediatrics & Children’s Hospital Wisconsin Research Institute (CRI) at Medical College of Wisconsin (MCW), USA.
As rightly put by the Finance Minister Nirmala Sitharaman in her Budget speech: Covid-19 pandemic “is the dawn of a new era, one in which India is poised to be a land of New Hope”; the entire world is eyeing India as a front runner to eradicate the dreadful virus. The situation demands that India exponentially manufactures sufficient vaccines. The country now has a dual challenge: vaccinating its own people in a time-efficient way on one hand and supplying enough vaccines to the rest of the world on the other hand. In order to meet both the need, expanding collaborations at the interface of vaccine production and simultaneous manufacturing of multiple vaccines have become imperative. With India currently having two approved vaccines available; let us take a deep dive and see what other options might commensurate to the Indian context in the near future.
Efficacy is by far the most important factor while selecting a vaccine. Currently Bharat Biotech vaccine ‘Covaxin’ and Oxford-AstraZeneca vaccine ‘Covishield’ have shown >90% protection against Covid-19 and also demonstrated partial protection against at least one of the newer Covid-19 variants. Two other vaccines respectively from Pfizer and Moderna, which are already clinically approved and currently being administered in the UK and the US along with several other nations have shown remarkable success thus far. It may be noted that the results of the phase-III clinical trials confirm and endorse the actual efficacy of any vaccine. There are currently 20 more vaccine candidates worldwide that already entered a phase-III clinical trial and many of them if not all, hopefully, will be approved anytime soon. These include but not limited to the candidates from Novavax, Janssen, Inovio, Gamaleya, Moderna and Pfizer. Interestingly among all these candidates, Sputnik V from Gamaleya has shown remarkable results as published in top-tier international medical journal ‘Lancet’. One key success of this vaccine is that it is almost equally protective even in the recipients of >60 years old. However, the efficacy of this promising vaccine is yet to be tested and proven against Covid-19 mutants like South African, Brazilian or UK strains.
Although Pfizer previously pursued its request for India to approve its Covid-19 vaccine, the US based pharma giant withdrew the application for emergency use of its Covid-19 vaccine in India. However, it is also reported that the company will continue to engage with the government authority and re-submit its approval request with necessary additional information. Meanwhile, Tata Group’s newly launched medical venture Tata Medical & Diagnostics showed interest in Moderna’s vaccine and considering necessary clinical trials in association with the Council of Scientific & Industrial Research (CSIR).
Safety and immunogenicity are the factors; the Indian government should carefully look at it while making a choice. One of the safety parameters remains post vaccination lower rate of severe adverse events (SAEs). According to the reports of Independent Data Monitoring Committee (IDMC) for SAEs of current or prospective vaccines as discussed thus far, Gamaleya stands at 0.27%, Pfizer at 0.58%, AstraZeneca at 0.66% and Moderna at 0.97%. Among several other factors, the immunogenicity and efficacy of a given vaccine also depend on host genetic factors. In addition to this, genetic predisposition to Covid-19 is not yet known. On this note, although Pfizer and Moderna’s vaccines are ~95% effective, participants of clinical trials were largely confined to the white population while Asians remained at paltry <5%. Thus, it is not yet known whether these vaccines are equally effective among the Indian population. Although Sputnik V underwent limited clinical trial among the Indian population, the genetic concern remained pertinent for any vaccines other than Covaxin.
The success story in defeating this pandemic in the coming days would not rely only on the vaccine itself, but also on logistics and awareness. It is important to understand whether a certain vaccine regardless of its efficacy, is logistically conducive for the Indian terrain or not. While mRNA vaccines such as Pfizer’s one need to be stored at -70ºC; Sputnik V along with currently approved Covishield or Covaxin can be stored at +2º+8ºC, giving it an edge over other existing or upcoming genetic material-based vaccines. However, a catch-22 situation may arise where the government needs to be judicious in choosing between a marginally less effective but ‘easy to transport’ vaccine versus a more effective but ‘difficult to transport’ one.
We should also learn from what was observed in the US and the UK that in terms of awareness towards the need of urgent vaccination, vast heterogeneity exists among different sub-populations. Indian government should potentially consider this on the domestic front, coordinate with various government agencies and local authorities, and take proactive measures to steer countrywide homogenous mass-awareness on the need and getting vaccinated to achieve herd immunity and prevent any further catastrophe. Therefore, collaboration not only between the government and vaccine manufacturers, but also between government and mass people is the key to win over this pandemic.