ASCO data won't help AZ's Calquence rival Imbruvica in CLL: analyst

AstraZeneca's Calquence is looking to take on Johnson & Johnson and AbbVie's Imbruvica in chronic lymphocytic leukemia. (AbbVie)

When it comes to chronic lymphocytic leukemia, AstraZeneca is looking to push blockbuster Imbruvica aside with newcomer Calquence. But based on some new data, one analyst doesn’t see it happening.

After reviewing abstracts released in advance of the American Society of Clinical Oncology annual meeting, UBS’ Michael Leuchten concluded that replacing Imbruvica, Johnson & Johnson and AbbVie’s incumbent drug in the field, was “not going to be easy” for Calquence in CLL.

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Data from a phase 2 study of patients who had discontinued Imbruvica use after suffering side effects showed “that Calquence has a place as a second line treatment but not much more than that,” Leuchten wrote, adding that the abstract “doesn’t show us anything surprising.”

Had the abstract indicated a subgroup analysis of CLL patients with a genetic mutation known as the 17p deletion was on the way—and that those patients had responded positively to Calquence—that would have been “a different matter,” he noted, but “given that it isn’t mentioned in the abstract, this seems unlikely.”

A separate trial looking at three-year follow-up data with patients on a combination of Calquence and Roche’s Gazyvaro in both new and previously treated patients didn’t much surprise him, either, with the results coming out “consistent with prior presentations.” At the three-year mark, the percentage of Calquence patients who hadn’t seen their disease progress—94%, among new patients—“is maybe marginally better” than what researchers saw in a similar Imbruvica trial.

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Since even before Calquence won its first nod in 2017—to challenge Imbruvica in mantle cell lymphoma—industry watchers have been focused on the pair’s upcoming tussle in CLL. Earlier this month, Calquence took a step toward the battlefield with a phase 3 victory in CLL, with data showing it could top a pairing of Roche’s Rituxan and chemo at keeping disease at bay among previously treated patients.

But if AZ wants to make a serious dent in Imbruvica’s CLL share, it’s going to need head-to-head data, Leuchten predicted. And that won’t be around for a while, with only one trial, for high-risk CLL patients only, currently in progress and set to wrap up late next year.

“The ASCO abstracts help little to further the debate,” he wrote.