When Pfizer acquired Array Biopharma for $11.4 billion three years ago, the focus was FDA-approved cancer drugs. The buyout also came with drug candidates in development for other diseases, and this is the end of the road for one of them.
It’s Pfizer work stoppage of PF-07265893, a drug that has reached Phase 3 testing for symptomatic dilated cardiomyopathy, a type of heart muscle disease. The oral small molecule is designed to treat forms of the disease that result from a particular genetic mutation.
Symptoms of dilated cardiomyopathy include fatigue and shortness of breath. The condition, which has no specific FDA-approved treatment, can also lead to heart failure, which can be fatal. The Pfizer drug is designed to block a pathway involved in disease progression. In an open-label phase 2 trial, results showed improvement as measured by a test that measures the distance patients can walk within six minutes.
The six-minute walk test was also the primary endpoint of the placebo-controlled, 24-week phase 3 study of PF-07265893. Secondary objectives included assessment of six-minute walk at weeks 4 and 12 and assessment of change in Cardiomyopathy Questionnaire score. Pfizer said late Wednesday that an interim analysis showed the study was unlikely to meet its primary goal. The company did not release specific findings from that analysis, but said the decision to stop work on the drug was not based on safety concerns. More detailed data from the clinical trial will be presented at future medical meetings, the company said.
“This development confirms the complexity of developing new treatments for rare cardiovascular diseases and the need to further increase knowledge in this area,” Chris Boshoff, Pfizer’s chief development officer for oncology and rare diseases, said in a prepared statement. .
Phase 3 trial for PF-07265803 initiated under Array Biopharma. This Boulder, Colorado-based company has commercialized two cancer drugs, Braftovi and Mektovi, as a combination treatment for melanoma characterized by a particular genetic mutation. The acquisition of Array by Pfizer in 2019 followed positive phase 3 data testing the drug combination in colorectal cancer.
Braftovi won additional approval for colorectal cancer in 2020. Under Pfizer, neither Braftovi nor Mektovi became big sellers. Braftovi reported $187 million in revenue last year, according to Pfizer’s 2021 annual report. Mektovi reported $155 million in sales.
Pfizer said it is working with regulators, clinical trial investigators and community groups to end the PF-07265893 clinical trial.
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