Merck received interim results from his trials this month.
Merck & Co. halted the development of its two experimental Covid-19 vaccines after early trial data showed that they could not elicit immune responses comparable to a natural infection or existing vaccines.
The American drug giant, which has a long history of successfully developing vaccines, has adopted a different strategy than rivals Pfizer Inc., Moderna Inc. and Johnson & Johnson, with a more traditional approach to focusing on shots based on attenuated viruses. One, called V590, borrowed technology from Merck’s Ebola vaccination, while the other, V591, is based on a measles vaccine used in Europe.
Both V590 and V591 were lagging behind in the vaccine development race. Merck completed the recruitment of the first participants for early-stage safety studies at the end of 2020, when the forerunners Pfizer and Moderna prepared to report late-stage data on the effectiveness of their shots. Merck received interim results from his trials this month.
The results were ‘disappointing and a little surprising,’ said Nick Kartsonis, senior vice president of clinical research for infectious diseases and vaccines at Merck Research Laboratories. Both shots caused fewer neutralizing antibodies to stop infections than other Covid-19 vaccines, and elicited fewer immune responses compared to people who contracted the coronavirus.
“We did not have the need to move forward,” Kartsonis said in an interview Sunday. After evaluating the data, Merck’s senior leadership decided to discontinue the programs and divert resources to the company’s efforts to develop Covid-19 treatments.
Vaccination
Although Merck’s vaccines are not expected to be part of the initial vaccination pressure in the US, the development comes amid heightened anxiety about the supply of vaccines and a slow pace of injections. The emergence of new variants of the coronavirus has also raised questions as to whether the shots that have been cleaned will lose their effectiveness as the pathogen mutates.
The failure of Merck’s candidates will also rule it out in a market that could eventually be dominated by two of its historic American rivals. Pfizer was the first drug manufacturer to obtain authorization for a Covid vaccine in the US, followed by Moderna, and in the coming weeks Johnson & Johnson is expected to publish data on the efficacy of the vaccine and apply for an emergency permit.
None of Merck’s candidates ended up among the six primary vaccines in the U.S. government’s Operation Warp Speed portfolio, although his leadership kept a close eye on them. The drug manufacturer and its partner, the International AIDS Vaccine Initiative (IAVI), did receive research funding from the government. Both candidates would have been a single dose of shots.
Kenckworth, Merck, based in New Jersey, will file a pre-tax levy for the fourth quarter of 2020 for costs associated with discontinuing the programs. The amount of the charge was not disclosed on Monday. The early stage of the trial results will be submitted to a peer-reviewed medical journal.
Two coronavirus vaccines have been cleared for use in the US, but a steady increase in infections has highlighted the need for more treatment options. According to Kartsonis, Merck will send resources to two drugs he has in the late stages of development to combat the disease.
“In the world of pharmaceutical development, a quick kill is not a bad thing because it allows you to reposition and reuse your assets,” he said.
Several of Merck’s vaccine manufacturing facilities are being rebuilt to produce one of its Covid-19 drug candidates, MK-7110, which is complex and difficult to manufacture on a mass scale. In an interim study, intravenous therapy significantly improved the likelihood and speed of recovery for severe and critical Covid-19 patients requiring oxygen, which reduced the risk of respiratory failure and death by more than 50%. Full study results are expected in the first term.
Merck executives expect U.S. regulators to authorize the use of the drug in emergencies after the results, and Kartsonis said it could reach sick patients by the middle of the year. The US has already agreed to pay $ 365 million for 60,000 to 100,000 doses.
Antiviral pill
Merck is also working on a pill for Covid-19 patients in earlier stages of the disease. The antiviral therapy, known as molnupiravir, was discovered by scientists at Emory University and is being studied in late stages in both hospitals and outpatients. Merck and partner Ridgeback Biotherapeutics MPs expect to have initial data on the drug’s efficacy in the first quarter, and to complete studies in May, the company said in a statement.
Chief Marketing Officer Michael Nally said in December that Merck expected regulatory approval shortly after the company reported data, should it be successful.
The antiviral drug is intended to be taken twice daily for five days, for a total of ten capsules. Merck predicts that by 2021 it will be able to produce more than 20 million treatment durations, or 200 million capsules, Nally said.
The slow explosion of the vaccine shows that Kartsonis will continue to have a need for drugs, and that the drugs may work against future viruses.
(Except for the headline, this story was not processed by NDTV staff and is published from a syndicated feed.)