Israeli study concludes that paxlovid reduces deaths of elderly by Covid

Paxlovid, the Covid-19 drug developed by Pfizer, reduced hospitalizations and deaths of elderly patients during the wave of omicron in Israel earlier this year. But, according to new research, it made no difference for patients under the age of 65 and at high risk of becoming seriously ill.

The study is one of the first published analyzes of the actual effectiveness of paxlovid against the omicron, now the dominant version of the coronavirus. Pfizer ran the drug’s clinical trials during the delta variant wave last year, covering only unvaccinated people.

There were still doubts about the effectiveness of the drug against the omicron variant and among vaccinated patients or who have some immunity because they have had Covid before. Paxlovid has been available to Americans since December.

The new study did not address another pressing unknown: how often patients experience relapsed Covid cases after taking paxlovid. Jill Biden, the first lady of the USA, came out of a second period of isolation last Monday (29), having returned to present Covid after taking paxlovid.

On Friday, Ashish Jha, coordinator of the White House response to Covid, said on Twitter that while there is confusion regarding who should take paxlovid, the data still indicates that the drug should be given to anyone from 50 years shortly after she showed symptoms of Covid and also to anyone with health issues that leave her vulnerable to becoming seriously ill.

While the Israeli study concluded that paxlovid is of no benefit to adults aged 40 to 64 with comorbidities, other research has suggested that the drug may improve end results. A study done in Hong Kong, which has not yet been peer-reviewed or published in a scientific journal, reported benefits of the drug for patients aged 50 to 64.

Massachusetts General Brigham health system researchers reported that paxlovid significantly reduced hospitalizations among patients aged 50 to 64, with a pronounced effect on unvaccinated people and people with obesity.

Jha said on Twitter that there was no reason to think the drug’s benefits would only be felt by older or more vulnerable sections of the population. He pointed out that paxlovid has few side effects (most notably a metallic taste in the mouth) and that there is no shortage of the drug in the United States.

“It is clear that a drug that prevents replication of the virus in a 70-year-old patient will do the same in a 60-year-old patient,” Jha wrote. He noted that nearly 200,000 Americans aged 50 to 64 have already died from Covid.

Pfizer’s own studies found that paxlovid reduced the risk of hospitalizations and deaths by 88% among unvaccinated people who were at high risk for severe micron, as long as it was taken within the first five days after symptoms appeared.

Published on the 24th in The New England Journal of Medicine, the new research revealed that paxlovid is mainly effective with older patients with Covid.

“The important thing is that it works, saves a good number of lives and prevents a good number of hospitalizations,” said Dr. Ronen Arbel, first author of the study and an expert on health outcomes at Clalit Health Services in Tel Aviv. “It’s very important that he helps older patients.”

Other study authors included Yael Wolff Sagy, Doron Netzer and Ariel Hammerman, all of Clalit Health Services, a major healthcare provider in Israel. The researchers reviewed the medical records of nearly 110,000 Clalit members who tested positive for Covid between January and March, when the omicron variant was dominant.

Patients were at least 40 years of age and were considered to be at high risk of becoming seriously ill. Most of them had already been vaccinated, had previously been infected with Covid, or both. The mean age of patients was 60 years, and more than half were women.

About 4,000 patients were treated with paxlovid, and the drug proved highly effective when given to people aged 65 and over, the scientists found.

Among the 42,821 patients aged 65 and over, 766 who did not receive paxlovid were hospitalized with Covid, while only 11 who took the drug were hospitalized. The relative risk reduction was 73%.

Deaths were significantly reduced in paxlovid-treated elderly patients. Only two of 2,484 patients who received the drug died, compared with 158 of 40,337 untreated patients — a 79% risk reduction.

But the drug had little effect on younger adults, having no noticeable impact on deaths or hospitalizations, which were lower in this group than among older patients treated with paxlovid.

Arbel said that he and his colleagues had hoped to study the relapse phenomenon, but that the data on reported symptoms were not reliable enough to do so.

“I know it’s something that’s talked about a lot in the United States, but I’m not sure if anyone has died or been hospitalized” after a recurrence, he said. “Almost not relevant.”

While paxlovid doesn’t appear to have much of an impact on younger or middle-aged adults, Arbel said some doctors may still choose to prescribe the drug to patients under age 65.

“In the case of a 62-year-old person who is unvaccinated and has complications, it may be justified to prescribe the drug,” he said.

^{Translation by Clara Allain}