But similar to what happened with the Covid vaccines, the World Health Organization "is very concerned" that less wealthy countries will once again struggle to access this medicine. .

For WHO experts, the nirmatrelvir/ritonavir combination "is the drug of choice" for unvaccinated, elderly or immunocompromised patients, according to an article in the British Journal of Medicine.

For this same type of patients and symptoms, the WHO has also issued a "weak recommendation" for remdesivir from the American laboratory Gilead, which it had previously advised against.

Paxlovid should be preferred over Merck's molnupiravir or remdesivir as well as monoclonal antibodies, says the organization, which continues to campaign for vaccination.

"It is crucial to prevent people from developing a serious form of the disease, from dying. And vaccination is a key intervention for prevention", insisted Dr Janet Diaz, leader of the clinical team in charge of the response. to Covid-19 during a press briefing in Geneva.

Paxlovid "reduces the number of hospitalizations more than alternatives, has fewer potential risks than the antiviral molnupiravir, and is easier to administer than intravenous options such as remdesivir and antibody treatments".

The studies showed 84 fewer hospital admissions per 1,000 patients, no "significant difference in terms of mortality" and "little or no risk of complications leading to the cessation of treatment", underlines the WHO.

This recommendation applies to people aged 18 and under and does not apply to pregnant and breastfeeding women.

It also does not apply to patients who are at low risk of complications because the positive effects are minimal.

The experts also declined to give an opinion regarding patients with a severe form of the disease due to lack of data.

Restrictions

However, the WHO emphasizes the limitations of these antiviral treatments: they must in particular be “administered as early as possible in the onset of the disease” which also supposes access to tests allowing the infection to be detected and to a doctor to confirm. diagnosis and prescribe medication.

Paxlovid must therefore be taken orally for 5 consecutive days and especially less than 5 days after the onset of symptoms.

In the case of remdesivir it is up to 7 days after the onset of symptoms and it must be given intravenously over three days.

A barrier in low- and middle-income countries.

As for cost and availability, the WHO calls on Pfizer to be more transparent and more open.

According to Dr Lisa Hedman, WHO Drug Access Officer, US public radio NPR revealed a cost of US$530 for a full course of paxlovid in the US, another source unconfirmed by WHO reporting a price of around USD 250 in an upper middle income country.

For remdesivir, the cost per ampoule is 520 USD, explained Lisa Hedman, but 53 to 64 dollars for those developed by generic companies in India.

There also remains a question mark regarding the risk of emergence of resistance to these treatments of the virus giving rise to Covid-19.

wind in its sails

In mid-April, Albert Bourla, CEO of Pfizer predicted a bright future for treatments like paxlovid because the disease is becoming endemic, but also because of a certain vaccine fatigue.

Accused, like its competitors, of having deprived the least wealthy countries of its messenger RNA anti-covid vaccine to serve high-income countries, Pfizer has concluded licensing agreements under the aegis of the United Nations, making it possible to manufacture a generic version. cheaper than paxlovid.

But the WHO "strongly recommends" that Pfizer go further with more transparent prices and contracts and an expanded license base so that more generic companies can produce the drug.

© 2022 AFP