By INS Contributors

KUALA LUMPUR, Malaysia--“The news that Pfizer Inc has successfully developed an antiviral pill against COVID-19 is indeed exciting,” says virologist, Emeritus Professor Dato’ Dr. Lam Sai Kit.

According to a press release by Pfizer, its experimental pill to treat COVID-19 has been shown to reduce the chance of hospitalization or death for adults at risk of severe disease by 89 percent.

The clinical trial using this drug was stopped prematurely because of overwhelming efficacy and the company planned to submit the findings to US regulatory authorities for emergency authorization as soon as possible.

In the Pfizer’s trial involving 1,219 unvaccinated adults, only 0.8 percent of people on a five- day treatment regime became sick and ended up in hospital and no one died.

In the placebo group, 7 percent of people ended up in hospital or died within five days of symptom onset.

“This is highly significant statistically, and we await the publication of its data in a medical journal soon. This has important implications for patients globally.”

This Pfizer’s pill comes soon after the approval of the Merck’s antiviral drug, molnupiravir, which has already gained approval for use in the UK. Malaysia has also placed an order for 150,000 courses of molnupiravir at the reported cost of RM420 million.

Molnupiravir is an antiviral medication working at the RNA polymerase gene level to prevent virus replication.

The Pfizer pill, with the brand name Paxlovid, works to block a crucial enzyme (protease inhibitor) that the SARS-CoV-2 needs to replicate.

Both the Pfizer and Merck drugs are taken orally, twice a day for five days. Merck’s showed a 50 percent reduction in hospitalization or death in a trial involving 385 patients and 377 controls who got placebo.

“The Merck trial was also stopped early because the results were so encouraging, showing that it can work against the most common SARS- CoV-2 variants, including delta and gamma.”

“Although antiviral drugs are going to be made available, the cost may be so prohibitive that it will be the deciding factor to its use globally. Merck’s US contract price is around USD700 for a five-day course. 

 
"We do not know what the Pfizer pill for a five-day course will be. The company is in active discussions with 90 countries, stating that its price will be close to that of Merck but will consider several lower options for low-income countries.”

Production to meet the global demand will be challenging. Merck expects to produce 10 million courses by the end of the year and has announced voluntary licensing agreements with generic-drug manufacturers in India to accelerate molnupiravir’s availability to low- and middle-income countries.

As for Pfizer, it is targeting to produce more than 180,000 packs of the drug by the end of this year, with a projected production of 50 million packs by the end of 2022.

“As with all antiviral drugs, both Merck and Pfizer pills must be given as early as possible to maximize their effectiveness. Pfizer’s pill is given in combination with an older viral drug called ritonavir, and possible side effects include nausea and diarrhea. 
 
"We also would like to know whether these pills can be given to prevent infection among those not vaccinated, including young children, and those older age groups and people with weakened immune systems or with comorbidities and at higher risk of severe infection if someone in the household has COVID-19. Further trials are still in progress in order to gather larger data sets and new information.”

Could these pills replace the need for vaccines?

“The simple answer is No. Vaccination is still the most effective protection against COVID-19. These oral medications will help in reducing the risk of severe disease, hospitalization, and death, leading to huge savings. But it still does not prevent infection. The vaccine rollout of more than 7 billion doses globally has only covered half the world’s population, and many have been reluctant to be vaccinated. 
 
"I hope more people will agree to be vaccinated and accept the third dose for better protection. We must continue to practice social and public health measures such as wearing masks, maintaining physical distance, and regular handwashing, until we reach the stage where over 80 percent of our total population, including children, are vaccinated. For now, the news about the availability of antiviral drugs is indeed exciting news as we have an additional tool to fight back against COVID-19," he said.