Why does the EMA recommend not using Paxlovid with some immunosuppressants?
Paxlovid, Pfizer's anti-Covid pill, could cause serious and potentially fatal adverse reactions if administered with some immunosuppressants. Here's which ones and why
It has never had great success , not even in Italy. Pfizer's anti-Covid pill, Paxlovid, suffers a new setback. The European Medicines Agency (EMA) has in fact reminded healthcare professionals of the risk of serious and potentially fatal adverse reactions that could result if used in combination with some immunosuppressants.
THE EMA RECOMMENDATION
The EMA Safety Committee (PRAC) reiterated to healthcare professionals the risk of serious and potentially fatal adverse reactions with Paxlovid (nirmatrelvir, ritonavir) if used in combination with some immunosuppressants that have a narrow safe dosage range (in which small changes in dose can lead to serious adverse reactions), due to drug interactions that reduce the body's ability to eliminate these drugs.
Paxlovid is an antiviral indicated for non-hospitalized Covid patients with mild or moderate disease, who do not require supplementary oxygen, but who are at risk of developing severe disease. In these cases it is essential to administer it within 5 days of the onset of symptoms.
WHICH IMMUNOSUPPRESSORS CANNOT BE COMBINED WITH PAXLOVID
The immunosuppressants involved, writes the EMA, are those defined as calcineurin inhibitors (tacrolimus, ciclosporin) and mTOR inhibitors (everolimus, sirolimus), which reduce the activity of the immune system and are used for the treatment of some autoimmune or to prevent the body from rejecting the transplanted organs.
“Paxlovid – we read – should be administered with tacrolimus, ciclosporin, everolimus or sirolimus only if close and regular monitoring of their blood levels is possible, to reduce the risk of drug interactions causing serious reactions”.
However, it should not be administered in combination with drugs whose elimination from the body depends largely on a series of liver enzymes (proteins), known as CYP3A, and which also have a narrow safe dosage range, including immunosuppressant voclosporin.
CASES OF TOXICITY
The risk of such interactions was already known and described in the information relating to Paxlovid but following the evaluation of all available evidence, including reports of serious adverse reactions, some of which were fatal, the PRAC deemed it appropriate to send a direct communication to operators health workers since in several cases, the EMA reports, the blood levels of these immunosuppressants increased rapidly to reach toxic levels, with consequent danger to life.
PFIZER BUSINESS
Meanwhile, Pfizer's 2023 balance sheet , published last January 31, "certifies the collapse in demand for the Comirnaty vaccine and the anti-Covid treatment Paxlovid which, despite exceeding analysts' estimates in the fourth quarter, in fact reports the numbers of the pharmaceutical company American to normal after the boom of 2021-2022”, writes Milano Finanza .
However, adds MF , "the turnover of businesses not linked to Covid-19 is growing". 2023's $10.7 billion R&D investment, coupled with Seagen 's $43 billion acquisition to bolster its oncology division, treatments in development for pneumococcal pneumonia and sickle cell disease have made Pfizer confirm the objectives, revised in December, for 2024, with revenues between 58.5 and 61.5 billion dollars and an operational growth of 8-10%.
As MF observes, "danugliprom, the experimental anti-obesity medicine that Pfizer is testing to compete with Novo Nordisk and Eli Lilly, does not appear among the key programs indicated in the presentation to analysts".
This is a machine translation from Italian language of a post published on Start Magazine at the URL https://www.startmag.it/sanita/perche-lema-raccomanda-di-non-utilizzare-paxlovid-con-alcuni-immunosoppressori/ on Mon, 12 Feb 2024 13:38:06 +0000.