Cipla, Optimus get nod for phase 4 trials to check efficacy of Covid drug favipiravir

Study will note clinical improvement of Covid patients & assess safety of favipiravir. It will also see ‘mortality, disease progression & viral clearance’ at given stages.

Representational image of Favipiravir | ANI photo

New Delhi: A top government panel of experts has given its nod to pharma companies Cipla and Optimus Pharma to carry out phase 4 clinical trials to determine the efficacy of Covid-19 drug favipiravir.

The subject expert committee (SEC), which advises apex regulator Drug Controller General of India (DCGI) on applications seeking approvals for new drugs, vaccines, and clinical trials for Covid, gave its approval after the two favipiravir-manufacturing firms submitted their proposals.

Another drugmaker, BDR Pharma, has been asked to submit a revised proposal with the suggested changes.

The decision to allow phase 4 trials was made following detailed deliberations, according to the minutes of the SEC meeting held on 2 September.

Phase 4 or confirmatory trials refer to last-stage trials and are conducted to find answers to important questions about the effectiveness of the drug.

Antiviral favipiravir was developed in Japan and subsequently approved for use among influenza patients. It is among the most closely watched drugs under the trial for Covid treatment, along with Ebola drug remdesivir.

The panel asked the two companies to compare the phase 4 data with the already available literature on proving the efficacy of the drug on Covid patients, revealed the minutes uploaded on the website of the Central Drugs Standard Control Organisation (CDSCO), the health ministry arm that regulates the quality of drugs and vaccines in the country.

The CDSCO is led by the DCGI, who in turn, will give final approval to the trials.

In June, Glenmark became the first Indian firm to launch the drug in India after completing the phase 3 clinical trials. Later, several pharma companies launched the drug in the market.

Conditional approval 

The SEC’s approval is subject to conditions for both the firms. The panel has asked the companies to title the trial as “Phase IV Clinical Trial” and not just “study” to clearly reflect that the drug is already subjected to patients and is available in the market.

“Follow up period should be up to 28 days instead of 21 days,” it has said.

Moreover, the study will note the clinical improvement of the patient and assess the safety of the drug as its primary objectives. As secondary objectives, “mortality, disease progression and viral clearance at 4, 7, 14 days or at hospital discharge” will be noted.

Results raise questions on efficacy

According to the latest results, the drug has failed to show its efficacy on Covid patients.

In July, Japanese medical university, Fujita Health University, reportedly announced that the “clinical study of the antiviral drug Avigan (favipiravir brand) has failed to demonstrate a clear efficacy in treating coronavirus patients at an early stage of the disease”.

“The difference seen between the patients who took the drug immediately and those who took it later was not statistically relevant in assessing the effectiveness of the drug, developed by a subsidiary of Fujifilm Holdings Corp,” said the Kyodo News report quoting the university.

The report quoted Yohei Doi, a professor at the university who led the study, to say “there has been a tendency to bring down fever or eradicate the virus” in those administered with the drug.

But Doi added that the enrollment of 89 patients in the study was too small to yield a statistically meaningful difference.