AstraZeneca (AZ) has shared positive results from a late-stage study of its Bruton’s tyrosine kinase (BTK) inhibitor Calquence (acalabrutinib) in chronic lymphocytic leukaemia (CLL).
The phase 3 AMPLIFY trial has been evaluating the drug plus venetoclax, with and without obinutuzumab, compared to standard-of-care chemoimmunotherapy in adults with previously untreated CLL.
According to an interim analysis, the Calquence combination demonstrated a statistically significant and clinically meaningful improvement in progression-free survival (PFS) compared to chemoimmunotherapy.
A trend was also observed in favour of the combination for the secondary endpoint of overall survival (OS), but this data was not mature at the time of the analysis and the trial will continue to further assess OS.
CLL is the most prevalent type of leukaemia in adults globally, with approximately 4,000 new cases of the disease diagnosed every year in the UK alone.
Despite being considered an incurable cancer, patients often live with the disease for many years and may remain on continuous treatment.
Susan Galbraith, executive vice president, oncology research and development, AZ, said the results “demonstrate the potential of including a BTK inhibitor in a fixed-duration regimen”.
Principal investigator Jennifer Brown, Dana-Farber Cancer Institute and Harvard Medical School, said: “This is an important advance in this setting as fixed-duration regimens allow those living with [CLL] to take breaks from their treatment, thereby decreasing the possibility of long-term adverse events and drug resistance and improving quality of life.”
Calquence is already approved in Europe, the US and several other countries to treat certain cases of CLL.
“If approved, Calquence would become the only second-generation BTK inhibitor available as both a treat-to-progression and fixed-duration treatment, providing more options for patients and their healthcare providers,” Galbraith said.
AZ said the data will be presented at an upcoming medical meeting and shared with global regulatory authorities.
Beyond CLL, Calquence also holds approvals to treat certain patients with small lymphocytic lymphoma and mantle cell lymphoma (MCL).
The company shared positive results last month for the drug plus standard-of-care chemoimmunotherapy bendamustine and rituximab in adults with previously untreated MCL.
The combination reduced the risk of disease progression or death by 27% compared to chemoimmunotherapy. Median PFS was 66.4 months for patients treated with the Calquence combination versus 49.6 months for those receiving chemoimmunotherapy.