Pfizer gives up on Paxlovid in less vulnerable COVID patients after data fail to impress
www.fiercepharma.com
By Angus LiuJun 15, 2022 10:20pm
Pfizer’s Paxlovid has proven useful in COVID-19 patients at high risk of severe disease. But the antiviral drug may not help less vulnerable patients.
Pfizer has stopped enrollment into the EPIC-SR trial that’s been evaluating Paxlovid in standard-risk patients, the company said Tuesday. These include unvaccinated adults without additional risk and vaccinated people who have at least one risk factor for progressing to severe disease.
The clinical trial previously flopped on its primary goal, showing the Pfizer antiviral was no better than placebo at sustaining symptom relief for four consecutive days. Now, the company is calling it quits on the study after finding it hard to read any signs of potential benefit because of an already low rate of hospitalization or death in the standard-risk population.
Pfizer “will continue to evaluate treatment in populations with high unmet need,” the company said.
Back in December, Pfizer unveiled an interim analysis of EPIC-SR, showing a 70% relative risk reduction in hospitalization or death for Paxlovid over placebo in standard-risk patients. But the number failed to cross the statistical significance bar because unlike high-risk patients, the EPIC-SR population already has very low risk of disease worsening.
After investigators counted more patients, the relative risk reduction narrowed to 51% and was still not statistically significant. Speaking to the low underlying risk, only 10 of 569 patients on placebo had progressed to severe COVID, compared with five of 576 patients in the Paxlovid arm.
The number was similar in a subgroup of vaccinated adults with at list one risk factor. In those patients, Paxlovid charted a 57% reduction in the risk of hospitalization or death, with a small number of cases in both study arms. The Pfizer drug also showed a non-significant 62% decrease in COVID-related medical visits per day across all patients.
Still, after the trial missed its primary endpoint of continuous symptom relief, the other endpoints look less important.
The standard-risk population marks another setting where Paxlovid has failed to move the needle. In April, Pfizer said the oral antiviral wasn’t effective at preventing COVID infection in people exposed to the coronavirus through household contact.
Pfizer managed to chalk up a positive sign from the failed EPIC-SR trial. The reductions were consistent with those in the EPIC-HR study in high-risk patients, for whom Pfizer plans to file Paxlovid for a full FDA approval.
As COVID caused by the dominant omicron variant generally causes milder disease, the global demand for Paxlovid has reportedly waned. But Pfizer has recently reconfirmed its projection that Paxlovid will reach $22 billion global sales this year.
Meanwhile, development of COVID antivirals is starting to shift from examining hospitalization and death risk for at-risk patients to alleviating symptoms. This development path resembles that of antivirals for influenza, which also causes fewer severe cases.
A few weeks ago, China’s Junshi Biosciences said its antiviral drug, coded VV116, was statistically superior to Paxlovid in that it required a shorter median time to sustained clinical recovery in a Chinese clinical trial of high-risk patients. The drug also showed “a trend toward superiority” to Paxlovid in the time to sustained disappearance of clinical symptoms, which sounds a bit similar to the primary endpoint of Paxlovid’s EPIC-SR study. But that trial design triggered wide criticism because Paxlovid is only known to lower the risk of hospitalization or death.
www.fiercepharma.com
By Angus LiuJun 15, 2022 10:20pm
Pfizer’s Paxlovid has proven useful in COVID-19 patients at high risk of severe disease. But the antiviral drug may not help less vulnerable patients.
Pfizer has stopped enrollment into the EPIC-SR trial that’s been evaluating Paxlovid in standard-risk patients, the company said Tuesday. These include unvaccinated adults without additional risk and vaccinated people who have at least one risk factor for progressing to severe disease.
The clinical trial previously flopped on its primary goal, showing the Pfizer antiviral was no better than placebo at sustaining symptom relief for four consecutive days. Now, the company is calling it quits on the study after finding it hard to read any signs of potential benefit because of an already low rate of hospitalization or death in the standard-risk population.
Pfizer “will continue to evaluate treatment in populations with high unmet need,” the company said.
Back in December, Pfizer unveiled an interim analysis of EPIC-SR, showing a 70% relative risk reduction in hospitalization or death for Paxlovid over placebo in standard-risk patients. But the number failed to cross the statistical significance bar because unlike high-risk patients, the EPIC-SR population already has very low risk of disease worsening.
After investigators counted more patients, the relative risk reduction narrowed to 51% and was still not statistically significant. Speaking to the low underlying risk, only 10 of 569 patients on placebo had progressed to severe COVID, compared with five of 576 patients in the Paxlovid arm.
The number was similar in a subgroup of vaccinated adults with at list one risk factor. In those patients, Paxlovid charted a 57% reduction in the risk of hospitalization or death, with a small number of cases in both study arms. The Pfizer drug also showed a non-significant 62% decrease in COVID-related medical visits per day across all patients.
Still, after the trial missed its primary endpoint of continuous symptom relief, the other endpoints look less important.
The standard-risk population marks another setting where Paxlovid has failed to move the needle. In April, Pfizer said the oral antiviral wasn’t effective at preventing COVID infection in people exposed to the coronavirus through household contact.
Pfizer managed to chalk up a positive sign from the failed EPIC-SR trial. The reductions were consistent with those in the EPIC-HR study in high-risk patients, for whom Pfizer plans to file Paxlovid for a full FDA approval.
As COVID caused by the dominant omicron variant generally causes milder disease, the global demand for Paxlovid has reportedly waned. But Pfizer has recently reconfirmed its projection that Paxlovid will reach $22 billion global sales this year.
Meanwhile, development of COVID antivirals is starting to shift from examining hospitalization and death risk for at-risk patients to alleviating symptoms. This development path resembles that of antivirals for influenza, which also causes fewer severe cases.
A few weeks ago, China’s Junshi Biosciences said its antiviral drug, coded VV116, was statistically superior to Paxlovid in that it required a shorter median time to sustained clinical recovery in a Chinese clinical trial of high-risk patients. The drug also showed “a trend toward superiority” to Paxlovid in the time to sustained disappearance of clinical symptoms, which sounds a bit similar to the primary endpoint of Paxlovid’s EPIC-SR study. But that trial design triggered wide criticism because Paxlovid is only known to lower the risk of hospitalization or death.
