Merck has protected Covid’s safety record antiretroviral drugs and claims that a rival treatment developed by Pfizer will cause problems for some patients taking the drug for other medical conditions.
Criticism of rival Merck’s product comes as the US Food and Drug Administration is weighing whether to authorize its antiviral drug molnupiravir, an easy-to-use oral treatment. first use for Covid-19 or not.
Last week, a group of outside experts at the FDA voted However, some members have raised concerns about the drug’s effectiveness and safety, including whether it could cause birth defects if used by pregnant women or potentially help with birth defects. new Covid or not.
In an interview with the Financial Times, Eliav Barr, Merck’s senior vice president of global health, said both antiviral drugs are needed to protect people from the virus because one Some patients may not be able to take one or the other treatments due to possible side effects.
However, the requirement that Pfizer’s antiretroviral tablets be used with ritonavir, a drug used to treat HIV, would make treatment unsuitable for many people with conditions ranging from before, he added.
“Ritonavir, which has been used in the treatment of HIV for many years, is a specific drug that inhibits the body’s ability to break down the drug,” Barr said. “The problem is it’s extremely nonspecific. So there are a lot of drugs that people take, especially those that, unfortunately, are associated with conditions that pose a risk. “
Research published in the scientific journal Nature last week identified a “high overall frequency” of drug-drug interactions among high-risk Covid-19 patients in Spain who were treated with the antiviral drugs lopinavir and ritonavir during hospitalization. Such interactions have been “alarmingly overlooked in the context of the Covid-19 healthcare crisis,” the study’s authors concluded.
Pfizer says ritonavir has a good safety profile when used alone or in combination with other drugs. While it can lead to drug interactions, they can be managed in many cases, it added.
“For drugs that share the same drug metabolism as Pfizer’s oral antivirals, within a five-day period most patients should be able to adjust their dose and then return to normal dosage after completion of oral antiviral regimen. ,” said a Pfizer spokesperson.
The licensing and commercialization of molnupiravir is important to Merck, unlike Pfizer which has not developed a Covid-19 vaccine. If the FDA grants emergency use authorization for the drug, the US government has a contract to buy 3.1 million courses for $2.2 billion.
Shares of Merck have lost 17% of their value over the past month after the release of data showing Pfizer’s antiviral drug Paxlovid was more effective than molnupiravir in reducing the risk of Covid-19 hospitalization or death.
UK and EU regulators granted emergency or conditional use approval for the treatment last month.
However, the license was granted before Merck released final clinical trial data showing the drug to be 30% effective in reducing the risk of hospitalization and death in high-risk patients. This is a lot lower than the 50% efficiency Merck announced in October from a preliminary analysis of the data.
Last week Citi downgraded Merck from “buy” to “neutral”, noting that the “clinical record of [molnupiravir] continues to deteriorate”.
Barr at Merck said molnupiravir’s safety record is “very strong” and many governments have expressed interest in buying its supply to fight Covid.