Available since Monday in Quebec, Paxlovid, nicknamed the “COVID the next day pill”, risks being difficult to access for the unvaccinated, contrary to what the federal government said last week.
For the time being, the limited number of doses of this oral treatment developed by Pfizer to prevent the complications of COVID-19, as well as the restrictions surrounding its use, risk that this drug — whose pharmacies have just received their first deliveries — more administered to patients targeted by hospitals.
“In theory, the ideal person to receive it is an unvaccinated person at risk of developing a serious illness. But in fact, as the distribution of Paxlovid is centralized in hospitals, it risks being the specialized clinics which will determine which are their patients at risk, those suffering from diseases which reduce the effectiveness of vaccines, ”explains the Dr Mathieu Simon, head of intensive care at the University Institute of Cardiology and Pneumology of Quebec (IUCPQ), Laval University.
Authorized by Health Canada last week, Paxlovid is intended for non-hospitalized patients at risk of developing complications related to COVID-19, but who have been infected for less than five days and who still have mild or moderate symptoms.
Hospital overload
“Many of the unvaccinated do not get tested, delay going to the hospital and arrive there very sick. It is less likely, in this case, that the ideal conditions are met to be candidates for this therapy, ”adds Dr.r Simon.
Whoever calls Paxlovid “the morning after pill” against COVID believes that this treatment will have little effect on the overload of the health network, where the unvaccinated account for 50% of hospitalizations in intensive care. “It won’t be a game changer “, he advances.
However, it will be very useful for patients who are already aware of their vulnerability to COVID. “Immunocompromised patients who have been wearing an N95 mask for two years know that they should contact the hospital right away if they have an infection, undergo a PCR test there and be evaluated to see if they qualify for this treatment,” he said.
Paxlovid could prevent up to 89% of deaths and hospitalizations in patients at risk (elderly, obese, hypertensive, diabetic, or presenting any other risk factor). But this treatment, combining a protease inhibitor and a very toxic antiretroviral (ritonavir), is contraindicated for a plethora of patients. “There are a lot of exclusions, especially for transplant patients, those with epilepsy, high cholesterol and many others,” says Dr.D Emily McDonald, a scientist with the Infectious Diseases Program at the Research Institute of the McGill University Health Center (MUHC), who has just published a meta-analysis on the effectiveness and cost of various anti-COVID outpatient treatments.
” 24 patients need to be treated with Paxlovid to avoid hospitalization. That’s a ratio three times more effective than other oral medications, like Fluvoxamine, which has a ratio of 1 in 80. Paxlovid costs $12,500 per treatment, but that’s less than the average cost of more $21,000 related to hospitalization for COVID,” she explains.
The Dr Donald Vinh, head of the Department of Infectious Diseases at the MUHC, says his hospital has received its first shipments of Paxlovid. The infectiologists on duty will evaluate this week the patients in hematology, oncology and transplant who are able to receive it, then any possibility of serious drug interaction must be ruled out before this shock treatment of five days (30 pills) is prescribed.
“Paxlovid is simple to administer, but so targeted that it won’t appeal to the general public,” he says. For example, Paxlovid cannot be used in children and pregnant women at risk of developing complications, due to its high level of toxicity, says DD Julie Autmizguine, pediatric infectious disease specialist at the Sainte-Justine University Hospital Center (CHU).
The vaccine first
“Better to be adequately vaccinated than to rely on this very inaccessible treatment,” says Dr.r Vinh, who still hopes that this treatment will avoid hospitalizations.
Many other anti-COVID treatments given to infected patients also have variable results, underlines the DD Emily Mcdonald.
In its comparative study, it assessed that inhaled corticosteroids and Fluvoxamine (two common and very inexpensive drugs) should be given to between 70 and 90 patients to avoid hospitalization. “They have a less spectacular effect than Paxlovid, but they are easy to administer and very rarely contraindicated. They are underused, even if our study shows that it remains interesting on a societal level to prevent hospitalizations, ”she says.
The good old corticosteroids have completely changed the prognosis of patients and the number of admissions to intensive care, assures the Dr Mathieu Simon, from the IUCPQ.
As for monoclonal antibodies (derived from the serum of infected patients reproduced by biogenetics), only sotrovimab, administered intravenously at the start of infection to patients at risk, remains useful against Omicron, ensures the DD Mcdonalds. But hospitals have access to it bit by bit. “In the United States, newly infected patients can go to monoclonal antibody clinics without a prescription. Our governments should increase the number of doses available,” she argues.
Even if the impact of these last very expensive treatments (about $50,000) to prevent hospitalization is considered “moderate”, it remains one of the few weapons available against hospitalization and the risk of developing severe COVID in patients. at risk, say these doctors. At CHU Sainte-Justine, a dozen at-risk mothers and children over 12 have had access to it. “None of these patients or any of these children developed severe forms of COVID,” says Dr.D Julie Autmizguine. It’s hard to say if they would have been hospitalized without it. This is only given in exceptional cases. »