AstraZeneca’s BTK inhibitor Calquence has won approval in the US for the treatment of chronic lymphocytic leukaemia (CLL) and small lymphocytic lymphoma (SLL), taking the fight to AbbVie/Johnson & Johnson’s Imbruvica.

The approval was based on two phase 3 trials of the therapy – ELEVATE-TN in patients with previously untreated CLL and ASCEND in patients with relapsed and refractory CLL.

The data from these trials showed that Calquence (acalabrutinib), both in combination with obinutuzumab or as a monotherapy, significantly reduced the risk of disease progression or death compared to the comparator arms.

The approval was one of the first to be granted under Project Orbis, an initiative of the US FDA Oncology Center of Excellence which provides a framework for concurrent submission and review of oncology medicines among international partners.

The FDA collaborated with the Australian Therapeutic Goods Administration and Health Canada on the review of Calquence.

Calquence is already approved in mantle cell lymphoma (MCL), its first indication. Now that it has approvals in CLL and SLL, AZ will hope to see it’s market share grow exponentially – if it can compete with rival Imbruvica (ibrutinib).

Imrbuvica (ibrutinib) is approved as a first- and second-line therapy for CLL, with sales of $3.6bn in 2018 and a target of $4.4bn this year across a broad range of haematological cancer indications.

“With over 20,000 new cases anticipated this year in the US alone, today’s approval of Calquence provides new hope for patients with one of the most common types of adult leukaemia, offering outstanding efficacy and a favourable tolerability profile,” said Dave Fredrickson, executive vice president, oncology business unit at AZ.

“The chronic lymphocytic leukaemia patient population is known to face multiple comorbidities, and tolerability is a critical factor in their treatment,” he added.

AZ also has additional studies of Calquence in diseases such as multiple myeloma, Waldenström marcroglobulinaemia and diffuse large B-cell lymphoma, and claims that it is already posing a strong challenge to AbbVie/J&J’s drug in MCL with a 40% share of new prescriptions in the indication.

Also looking to extend into the lymphoma market is BeiGene, which recently won approval in the US for its MCL therapy Brukinsa (zanubrutinib). The Chinese drugmaker's therapy is also in clinical development for CLL, SLL, follicular lymphoma and marginal zone lymphoma.