Emergency use of drugs or vaccines: What, when, how

The coronavirus pandemic has seen countries opting for emergency use authorisation of drugs and vaccines as never before. The United Arab Emirates (UAE) is the latest to allow the emergency use of the Covid-19 vaccine made by the Chinese state-owned pharmaceutical company, Sinopham, for its frontline workers.

The US Food and Drug Administration had recently allowed the emergency use of convalescent plasma therapy for Covid treatment, besides existing drugs such as Remdisivir. Several countries, including India, have frameworks for allowing such authorisations for drugs and vaccines.

When is emergency use authorisation of drugs or vaccines allowed?

If a regulator sees a reasonable likelihood of a drug being useful, and lives of people under threat if it is not used, it can allow use of that drug for a public health emergency. Drugs under trial can also be allowed through emergency authorisation for lifethreatening diseases, but on a case to case basis. This has been done especially for cancer patients who have exhausted all treatment options. It is an accelerated process that permits the regulator to grant permission under an emergency. It is different from regular market authorisation, which takes more time and requires more data on safety and efficacy to be shared with the regulator.

Such emergency authorisation has been allowed by countries, including the US, for infections such as Zika, the Ebola virus and Enterovirus D68 among others in the past.

For coronavirus, many drugs have received this approval for general use and not just for particular patients. As for vaccines, very few countries such as China and the UAE, have allowed such emergency authorisation for Covid vaccine. Russia has a temporary registration of its vaccine, Sputnik V, till January 2021 subject to the outcome of the Phase III trial.

What are the risks involved?

The World Health Organisation put in place an emergency use assessment and listing procedure after the 2014 Ebola outbreak for vaccine candidates. Its decision to allow such use is based on whether the information and documentation submitted provide sufficient evidence regarding quality, safety, and efficacy, and a riskbenefit analysis. Such a permission can also be withdrawn if it leads to adverse results in patients.

According to experts, there have been incidents in the past where the emergency use of vaccines such as BCG led to adverse effects. Such incidents can discourage the public from coming forward for vaccination. Some experts suggest that the government should widen the scope of vaccine trials to all parts of the country, instead of allowing emergency use which might lead to side effects.

What are the drugs that have been allowed for emergency use for treating Covid?

The US FDA allowed the use of antiviral drug Remdesivir in May for the treatment of suspected or laboratory-confirmed Covid-19 in adults and children hospitalised with severe disease, and also of Fresenius Propoven to maintain sedation in patients who required ventilators. It also revoked the use of chloroquine phosphate and hydroxychloroquine sulfate, saying that their known and potential benefits do not outweigh the known and potential risks.

Has India used this provision and what are the risks involved?

The Drug Controller General of India, under the provisions of the Drugs and Cosmetics Act, allowed the emergency use of Remdesivir and Favipiravir for the treatment of mild to moderate cases of Covid-19. The authorisation in some cases is granted with conditions such as a written consent and post-marketing surveillance by the drug company on a certain number of patients to check the safety and efficacy of the drug. It has also allowed emergency use of Biocon’s Itolizumab, which was previously approved for the treatment of psoriasis, a skin disease. The permission to Biocon’s drug was criticised for a very small size of group being studied in the phase 2 trials. The health ministry recently said that it has not received any application from any vaccine candidate for emergency use authorisation.