Pfizer Inc. plans to stop enrollment in a study of its COVID-19 drug in patients who aren’t at high risk of severe disease after the pill didn’t help alleviate their symptoms, a major setback for broader use of the treatment.
New York-based pharmaceutical company Paxlovid said Tuesday that it had stopped adding participants to the highly anticipated study. This was in response to low mortality and high risk patients with COVID. The decision comes after the study failed to demonstrate that the drug reduced COVID symptoms among relatively healthy patients and wasn’t able to show a statistically significant reduction in hospitalization and death.
Pfizer’s shares fell 0.1% in postmarket trading in New York. The results mark the latest blow to the company’s ambitions to expand the market for its blockbuster COVID pill. In late April, a study found that Paxlovid wasn’t successful as a preventive measure for people who had been exposed to the virus.
“The study shows the challenge of demonstrating a benefit of antiviral therapy in previously vaccinated or otherwise low risk individuals,” said Paul Sax, clinical director of the Division of Infectious Diseases at Brigham and Women’s Hospital in Boston. COVID-positive subjects were either fully or partially vaccinated and had at least one condition which increased the risk of serious illness.
Pfizer said in a statement that the study results aren’t expected to impact its full-year revenue forecast. Already, the drugmaker has secured contracts worth $22 billion for its COVID 2022 pill.
Drugmaker stated that it would focus its research on vulnerable populations such as those who have already been admitted or are immunecompromised.
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“With up to 40-50% of people around the world estimated to be high risk, we believe there remains a significant unmet need for treatment options to help combat this disease, and we will continue to prioritize efforts to advance the development of Paxlovid,” said Chief Executive Officer Albert Bourla in the statement.
Pfizer has posted the results of a Paxlovid trial on clinicaltrials.gov last month. The study will examine the safety and tolerance of the drug in small groups of pregnancies in their second to third trimesters. Paxlovid is being studied in children by the drugmaker. Soon, a study will be conducted in patients with compromised immune system.
In December, Pfizer reported early data from the study showing that Paxlovid failed to ease symptoms among so-called “standard risk” patients, and didn’t reduce the risk of hospitalization or death in a way that that was statistically significant.
The new results show the study once again didn’t meet its primary goal of self-reported alleviation of all symptoms for four consecutive days. And a secondary measurement of reducing the risk of hospitalization or death wasn’t statistically significant, given the small number of those outcomes in the study.
Paxlovid is currently authorized to use in an emergency situation for COVID treatment. It is temporary and can be withdrawn at any moment. Results from the study of standard-risk COVID patients will be submitted to the Food and Drug Administration as a part of Pfizer’s application for full approval of the product.
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