Contained in the race to discover a COVID-19 remedy capsule By Reuters


© Reuters. An experimental COVID-19 remedy capsule, known as molnupiravir and being developed by Merck & Co Inc and Ridgeback Biotherapeutics LP, is seen on this undated handout photograph launched by Merck & Co Inc and obtained by Reuters Might 17, 2021. Merck & Co Inc/Hand

By Deena Beasley

LOS ANGELES (Reuters) – In early 2020, as a brand new lethal coronavirus started spreading all over the world, Pfizer Inc (NYSE:) assembled what it known as a “SWAT crew” of scientists and chemists to establish a possible remedy to battle COVID-19.

The U.S. pharmaceutical large, which had begun exploring a vaccine, additionally needed to provide a capsule that would cease the an infection from progressing, much like how the widely-used Tamiflu drug fights influenza. The crew scoured Pfizer’s library of molecules searching for unused compounds to assist jumpstart the method, and shortly recognized a promising candidate.

Greater than a 12 months later, Pfizer has but to embark on large-scale human trials of a COVID-19 oral remedy – one thing it says it hopes to begin by July.

Pfizer and its rivals, together with U.S.-based Merck & Co Inc and Swiss pharmaceutical Roche Holding AG (OTC:), are racing to provide the primary antiviral capsule that folks might take at early indicators of the sickness. Their shared purpose: filling a key remedy gap by serving to individuals recently-infected with coronavirus to keep away from turning into severely unwell and needing hospitalization.

However after virtually 18 months of the pandemic, there may be nonetheless no easy-to-administer remedy confirmed to be efficient in opposition to COVID-19, the illness brought on by the coronavirus. That’s regardless of the event of numerous efficient COVID-19 vaccines, together with one from Pfizer and German companion BioNTech SE (NASDAQ:), which in December grew to become the primary to realize authorization to be used in the US.

Pfizer’s expertise underscores the challenges drugmakers face in growing an oral remedy for the virus. Not like a vaccine, which wants solely to set off the physique’s personal immune system, an efficient antiviral capsule should block a virus from spreading all through the physique whereas additionally being selective sufficient to keep away from interfering with wholesome cells.

Testing antivirals can also be tough, drug firm executives say. A drug must be given early in the middle of an an infection, which implies discovering trial members who’ve not too long ago contracted COVID-19. Many individuals contaminated with the virus develop solely gentle signs, however research must show {that a} drug has a significant affect on affected person well being.

Pfizer Chief Govt Albert Bourla has mentioned the corporate might search emergency authorization in the US for a COVID-19 capsule as quickly as late this 12 months.

“Proper now we have now superb purpose to consider that we may be profitable,” Bourla instructed an financial discussion board in Greece through video convention final week.

Pfizer and its rivals say the event course of has been a lot sooner than the a number of years it sometimes takes to provide a drug that may be taken as a capsule.

Merck and Roche not too long ago began late-stage human trials and have additionally mentioned their medication might be prepared by later this 12 months. Merck is growing its drug in partnership with biotech Ridgeback Biotherapeutics LP and Roche is working with Atea Prescribed drugs Inc.

Governments all over the world have poured billions of {dollars} into vaccine improvement, however Pfizer, Merck and Roche say they haven’t obtained authorities funding to develop oral antivirals for the illness.


Whereas the speed of latest COVID-19 infections is at present in retreat in some international locations, others proceed to wrestle with a speedy unfold of the virus. And with vaccines briefly provide in lots of international locations, a lot of the world is not going to be vaccinated for a number of years. Many individuals additionally stay reluctant to take vaccines.

Scientists forecast that COVID-19 – which has killed greater than 3.5 million individuals globally – might grow to be a seasonal illness much like influenza.

“We want a capsule that may preserve individuals out of the hospital,” mentioned Dr. Rajesh Gandhi, a professor and infectious illness specialist at Harvard Medical Faculty.

Docs have tried numerous current oral medication in combating COVID-19, however none of them have succeeded but in rigorous scientific testing.

At the moment, the one remedies proven to assist COVID-19 sufferers keep away from hospitalization are antibody medication that require prolonged intravenous infusions and work much less effectively in opposition to variants of the coronavirus.

Pfizer and its rivals say their oral antiviral candidates might be efficient in opposition to a broad spectrum of coronavirus variants, however no related information has been made public.

For sufferers already hospitalized with COVID-19, remedy usually entails steroids or anti-inflammatory medication to handle signs of the an infection, however these medicines don’t goal the virus itself. The one antiviral drug authorized in the US to deal with COVID-19 is Gilead Sciences (NASDAQ:) Inc’s remdesivir, which is delivered intravenously and used just for hospitalized sufferers.

Gilead is at present testing an inhaled type of remdesivir and is exploring different compounds that could be efficient oral brokers.

“We’re all on the hunt for the following Tamiflu,” mentioned Gilead Chief Medical Officer Merdad Parsey.

Tamiflu is advisable for individuals who have had flu for not more than two days and has been proven to shorten the length of flu signs.


Pfizer’s scientists and chemists started trying to find an antiviral remedy in January final 12 months. They shortly zeroed in on a compound from 2003, when the corporate had sought a remedy for the primary international SARS pandemic, mentioned Charlotte Allerton, Pfizer’s head of medication design.

The compound belongs to a category referred to as protease inhibitors, designed to dam a key enzyme, or protease, important to the flexibility of the coronavirus to multiply. Comparable medication are used to deal with different viral infections resembling HIV and hepatitis C, each on their very own and together with different antivirals.

Pfizer’s scientists hit an early stumbling block. Laboratory (NYSE:) testing confirmed the drug candidate was energetic in opposition to the novel coronavirus, referred to as SARS-CoV-2, however concentrations weren’t sturdy sufficient to fight the virus in people, Allerton mentioned.

Pfizer continued working with the energetic part of that compound to formulate a drug that might be given intravenously. However antivirals are most helpful for those who catch a illness early, “and that isn’t simple with an IV drug,” mentioned Allerton.

In March 2020, Pfizer scientists additionally began designing a brand new compound that might be absorbed by the abdomen and brought as a capsule, which they finalized in July, in keeping with Allerton.

Discovering a protease inhibitor that might be delivered orally was “a little bit of a chemistry masterpiece,” mentioned Pfizer Chief Scientific Officer Mikael Dolsten.

Antivirals are extra complicated to develop than vaccines as a result of they’ve to focus on the virus after it’s already replicating inside human cells, with out damaging wholesome cells. COVID-19 vaccines sometimes educate the human immune system to acknowledge and assault a portion of the “spike” protein that’s particular to the coronavirus.

A COVID capsule would possible be taken for just a few days, however drugmakers have needed to transfer slowly to make sure security.


The Merck and Roche drug candidates use totally different mechanisms to Pfizer’s, and to one another, to disrupt the replication equipment of the virus. However the firms share related challenges in testing.

One is making certain a affected person receives the drug quickly after an infection with COVID-19. “It is all about treating as early within the illness course of as potential, when the virus is increasing,” Pfizer’s Dolsten mentioned.

And with vaccination charges excessive in some areas, trials should be positioned in international locations the place COVID-19 remains to be on the rise.

In March of this 12 months, Pfizer started early-stage human trials in the US of its experimental oral COVID-19 remedy, referred to as PF-07321332. It adopted a separate trial by the corporate of the intravenous drug began final fall.

Dolsten declined to touch upon how the pending late-stage trials of both drug will probably be structured.

Merck’s antiviral drug candidate, known as molnupiravir, not too long ago had a setback. The corporate mentioned final month it could not pursue its use in hospitalized sufferers. However Merck mentioned it was shifting the drug into late-stage trials of a slender group of non-hospitalized sufferers – particularly those that have had signs for not more than 5 days and with not less than one danger issue for severe illness, resembling superior age, weight problems or diabetes.

Merck mentioned it might have definitive information by September or October.

Roche and its companion Atea are additionally limiting participation of their not too long ago launched late-stage trial of their AT-527 drug to COVID-19 sufferers experiencing signs for lower than 5 days. Atea mentioned ultimate trial outcomes are anticipated earlier than the tip of this 12 months.

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