COVID-19: treatments that have their limits

More than two years after the start of the COVID-19 pandemic, the medicine cabinet now has several treatments, but the use of these pills and injections has a number of limitations.

• Read also: Beijing announces strengthening of health measures

• Read also: Does hand sanitizer make a difference?

Although it is declining in a large majority of countries, COVID-19 has not gone away, and in addition to vaccines, drugs can make a difference to patients most at risk.

These treatments, which must be prevented and which must be cured, concern people for whom the vaccine is only slightly or ineffective (immunocompromised, etc.) or who are at high risk of serious forms and death, including the oldest.

But for now, “these effective drugs remain underused, the proof of this is the number of deaths,” laments AFP Antoine Flahault, director of the Institute of Global Health and professor at the Faculty of Medicine in Geneva.

“The main obstacle remains logistics,” he said. “Stakeholders should think about doing a PCR test in case of symptoms or risk contact, the attending physician should think about prescribing the right medicine, the pharmacy has it within the required short time, the hospital can receive and treat patients ” for medicines that are administered in hospital.

First category of treatment, antiviral pills act directly on the virus to prevent its multiplication.

Against COVID is Pfizer’s most advanced Paxlovid. The World Health Organization recommended a week ago giving preference to other treatments, including Merck’s less effective competing pill, molnupiravir.

And in mid-February, China gave Paxlovid a conditional green light. Good news for Pfizer, which plans to produce 120 million doses this year and already made $72 million last year for a much smaller amount.

But for now, doctors are struggling to prescribe these pills. In France, where Paxlovid is the only approved antiviral drug, 3,500 treatments were prescribed out of 100,000 administered in the first trimester. To further deploy it, the authorities want to facilitate its prescribing.

Likewise, the Joe Biden administration in the United States has taken action for the accessibility and recognition of anti-COVID pills. And Vice President Kamala Harris, who tested positive for COVID on Tuesday, is taking the Pfizer pills.

Nevertheless, several brakes are hoisted by specialists. First, the race against time to administer them: ideally less than five days from the onset of symptoms, confirmed by a test.

Some drugs, starting with Paxlovid, are also “delicate to use” because of “many interactions with other drugs,” Antoine Flahault specifies.

Another limitation: certain variants, such as Omicron, can reduce its effectiveness.

Second main category: monoclonal antibodies must be administered by infusion or injection in the hospital. They can reduce the risk of hospitalization and death by up to 80%.

These treatments, which target only one part of the virus, are used in two ways, depending on the drug chosen. Either they are used preventively in people who cannot be vaccinated, or they are given to hospitalized patients to prevent their COVID-19 from degenerating into complications.

The most important are Evusheld from the Swedish-British AstraZeneca and Ronapreve from the Swiss Roche, both used preventively, the second also curative. Added to this, as a curative, is Xevudy from British GlaxoSmithKline and American biotech Vir.

Again, the deadlines for managing it are tight.

And, even more than the pills, several of these biomedicines lose their effectiveness over the variants.

“The monoclonal antibodies effective against the Delta variant are no longer effective against Omicron-BA.1, the one that remained effective against BA.1 is no longer effective against BA.2,” a difficult-to-follow pace for research and prescription , notes Antoine Flahault.

If Evusheld still appears to protect against Omicron, a higher initial dose is sometimes recommended to make up for the lower effectiveness. Ronapreve is almost abandoned in several countries, given the total loss of neutralizing activity.

As with vaccines, access to anti-COVID drugs remains highly unequal between rich and poor countries. The lifting of patents was discussed again here, with some progress.

In late 2021, Pfizer and Merck announced licensing agreements under the UN umbrella, making it possible to produce a cheaper generic version of their pills. For example, in mid-March, agreements were signed with 35 generic manufacturers in Europe, Asia, Central and Latin America to produce and supply Paxlovid to 95 poor countries.

But the WHO said last Friday “very concerned” that less wealthy countries are still struggling to access Paxlovid. She “strongly recommended” that Pfizer move forward with more transparent pricing and contracts and an expanded licensing base so that more generics can manufacture the drug.

NGOs are still fighting. “If new treatments emerge, it will simply be inhumane if they are not available in a resource-constrained environment simply because they are patented and too expensive,” warned Marcio da Fonseca, an advisor for the Access to Medicines campaign, in early 2022. from Doctors Without Borders. †

Leave a Comment