Glenmark Pharmaceuticals Ltd said its trial of Favirpiravir showed a 28.6% faster recovery among those treated with the antiviral drug than on those who were on standard therapy.
The 150-person trial showed “numerical improvements for the primary efficacy endpoint with 28.6% faster viral clearance in the overall population as measured by the median time until cessation of oral shedding of virus in the Favipiravir treatment arm compared to those in the control arm,” the company said.
Glenmark is one of the several drug companies that are making the drug.
It became the first company to get regulatory nod in India to supply the drug last month.
Glenmark developed the favipiravir active pharmaceutical ingredient (API) and the formulation for its drug through its own inhouse R&D team.
Patients in the Glenmark Favipiravir clinical trial received Favipiravir tablets 3,600 mg (1,800 mg BID) (Day 1) + 1,600 mg (800 mg BID) (Day 2 or later) for up to maximum of 14 days, along with standard supportive care. Randomization was stratified based on disease severity into mild (90 patients) and moderate (60 patients).
There were some secondary benefits to observed in the trial, including 40% faster achievement of “clinical cure” defined as the physician’s assessment of normalization of clinical signs such as temperature, oxygen saturation, respiratory rate and cough with a statistically significant reduction in median time to clinical cure in the Favipiravir treatment arm (3 days), compared to the control arm (5 days).
The test also showed that 69.8% of patients in the Favipiravir treatment arm achieved clinical cure by Day 4, which was statistically significant compared to 44.9% observed in the control arm.
Amongst patients who clinically deteriorated and required oxygen support, those receiving Favipiravir had a longer median time to first time use of oxygen of 5 days versus 2 days in the control arm.
Additionally, Glenmark’s Favipiravir was well tolerated with no serious adverse events (SAEs) or deaths in the Favipiravir treated arm.
One SAE occurred in the control arm and resulted in death due to worsening clinical disease and acute respiratory distress syndrome (ARDS) attributed to COVID-19 infection.
Adverse events (AEs) were reported in 26 patients in the favipiravir treatment arm (35.6%) as compared to six patients in the control arm (8%).
However, most AEs were mild to moderate and none led to drug discontinuation or dosing adjustments.
The most commonly observed AE was asymptomatic transient increases in uric acid (12 patients in the Favipiravir treatment arm and zero in the control arm); most resolved on first follow up, Glenmark said.
Gastrointestinal disturbance was minimal and no clinically significant differences were observed between the treatment groups, it added.
Glenmark plans to submit the clinical trial data for publication in a peer-reviewed journal in the coming weeks and share its findings.
Dr Zarir Udwadia, one of the Principal Investigators of this study, called the results of the Indian Favipiravir study encouraging.
“The trial was performed with a sense of urgency considering the gravity of the pandemic, yet scientific principles were not sacrificed. I have had a chance to independently view the initial results and they are encouraging: Patients randomised to Favipiravir seemed to have faster clinical cure, and more importantly, faster viral clearance than those randomized to the routine care group.
“I eagerly await the final analysis and results from other ongoing studies from across the globe. Till then, I feel we have enough evidence to consider using Favipiravir in symptomatic COVID-19 patients who have mild to moderate infection.”
Dr Monika Tandon, Vice President & Head – Clinical Development, Global Specialty/Branded Portfolio at the company said the drug could potentially prevent patients from progressing to ARDS and mortality.
On June 20th, Glenmark announced that it received manufacturing and marketing approval from India’s drug regulator for FabiFlu, making it the first oral approved medication in India for the treatment of mild to moderate COVID-19.
The manufacturing and marketing approval was granted as part of an accelerated approval process, considering the emergency situation of the COVID-19 outbreak in India.
The approval’s restricted use entails responsible medication use where every patient must have signed informed consent before treatment initiation.
Glenmark has commenced a Post Marketing Surveillance (PMS) study on FabiFlu to closely monitor the efficacy and safety of the drug in 1000 patients that are prescribed with the oral antiviral, as part of an open label, multicenter, single arm study.
Glenmark is also conducting another Phase 3 clinical trial in India to evaluate the efficacy of two antiviral drugs Favipiravir and Umifenovir as a combination therapy in moderate hospitalized adult COVID-19 patients.
The combination study, which is called the FAITH trial, is looking to enroll 158 hospitalized patients of moderate COVID-19. Early treatment with combination therapy will be evaluated for safety and efficacy.
Favipiravir has been approved in Japan since 2014 for the treatment of novel or re-emerging influenza virus infections.
It is a broad-spectrum antiviral with a unique mechanism of action: it is converted into an active phosphoribosylated form (Favipiravir-RTP) in cells and recognized as a substrate by viral RNA polymerase, thereby inhibiting RNA polymerase activity and viral replication.
Favipiravir was granted approval in Russia for treatment of COVID-19 in May 2020 and is being prescribed to patients in multiple countries across the globe under compassionate use for the treatment of COVID-19 infection.
It also is being tested in close to 20 clinical trials across 3000+ COVID-19 patients globally, including ongoing clinical trials in the US, Canada, Japan and Italy.
Others who are, or plans for, manufacturing the drug in India including Dr Reddy’s Laboratories and Strides Pharma.